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  • Backing up my Windows Home Server to the Cloud&hellip;

    - by eddraper
    Ok, here’s my scenario: Windows Home Server with a little over 3TB of storage.  This includes many years of our home network’s PC backups, music, videos, etcetera. I’d like to get a backup off-site, and the existing APIs and apps such as CloudBerry Labs WHS Backup service are making it easy.  Now, all it’s down to is vendor and the cost of the actual storage.   So,  I thought I’d take a lazy Saturday morning and do some research on this and get the ball rolling.  What I discovered stunned me…   First off, the pricing for just about everything was loaded with complexity.  I learned that it wasn’t just about storage… it was about network usage, requests, sites, replication, and on and on. I really don’t see this as rocket science.  I have a disk image.  I want to put it in the cloud.  I’m not going to be be using it but once daily for incremental backups.  Sounds like a common scenario.  Yes, if “things get real” and my server goes down, I will need to bring down a lot of data and utilize a fair amount of vendor infrastructure.  However, this may never happen.  Offsite storage is an insurance policy.   The complexity of the cost structures, perhaps by design, create an environment where it’s incredibly hard to model bottom line costs and compare vendor all-up pricing.  As it is a “lazy Saturday morning,” I’m not in the mood for such antics and I decide to shirk the endeavor entirely.  Thus, I decided to simply fire up calc.exe and do some a simple arithmetic model based on price per GB.  I shuddered at the results.  Certainly something was wrong… did I misplace a decimal point?  Then I discovered CloudBerry’s own calculator.   Nope, I hadn’t misplaced those decimals after all.  Check it out (pricing based on 3174 GB):   Amazon S3 $398.00 per month $4761 per year Azure $396.75 per month $4761 per year Google $380.88 per month $4570.56 per year   Conclusion: Rampant crack smoking at vendors.  Seriously.  Out. Of. Their. Minds. Now, to Amazon’s credit, vision, and outright common sense, they had one offering which directly addresses my scenario:   Amazon Glacier $31.74 per month $380.88 per year   hmmm… It’s on the table.  Let’s see what it would cost to just buy some drives, an enclosure and cart them over to a friend’s house.   2 x 2TB Drives from NewEgg.com $199.99   Enclosure $39.99     $239.98   Carting data to back and forth to friend’s within walking distance pain   Leave drive unplugged at friend’s $0 for electricity   Possible data loss No way I can come and go every day.     I think I’ll think on this a bit more…

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  • SQL SERVER – Free Print Book on SQL Server Joes 2 Pros Kit

    - by pinaldave
    Rick Morelan and I were discussing earlier this month that what we can give back to the community. We believe our books are very much successful and very well received by the community. The five books are a journey from novice to expert. The books have changed many lives and helped many get jobs as well pass the SQL Certifications. Rick is from Seattle, USA and I am from Bangalore, India. There are 12 hours difference between us. We try to do weekly meeting to catch up on various personal and SQL related topics. Here is one of our recent conversations. Rick and Pinal Pinal: Good Morning Rick! Rick: Good Morning…err… Good Evening to you – Pinal! Pinal: Hey Rick, did you read the recent email which I sent you – one of our reader is thanking us for writing Joes 2 Pros series. He wants to dedicate his success to us. Can you believe it? Rick: Yeah, he is very kind but did you tell him that it is all because of his hard work on learning subject and we have very little contribution in his success. Pinal: Absolutely, I told him the same – I said we just wrote the book but it is he who learned from it and proved himself in his job. It is all him! We were just igniters. Rick: Good response. Pinal: Hey Rick! Are we doing enough for the community? What can we do more? Rick: Hmmm… Let us do something more. Pinal: Remember once we discussed the idea of if anyone who buys our Joes 2 Pros Combo Kit in the next 2 weeks – we will send them SQL Wait Stats for free. What do you say? Rick: I agree! Great Idea! Let us do it. Free Giveaway Well Rick and I liked the idea of doing more. We have decided to give away free SQL Server Wait Stats books to everybody who will purchase Joes 2 Pros Combo Kit between today (Oct 15, 2012) and Oct 26, 2012. This is not a contest or a lucky winner opportunity. Everybody who participates will qualify for it. Combo Availability USA – Amazon India - Flipkart | Indiaplaza Note1: USA kit contains FREE 5 DVDs. India Kit does not contain 5 DVDs due to legal issues. Note2: Indian Kit is priced at special Indian Economic Price. Qualify for Free Giveaway You must have purchased our Joes 2 Pros Combo Kit of 5 books between Oct 15, 2012 and Oct 26, 2012. Purchase before Oct 15, 2012 and after Oct 26, 2012 will not qualify for this giveaway. Send your original receipt (email, order details) to following addresses: “[email protected];[email protected]” with the subject line “Joes 2 Pros Kit Promotion Free Offer”. Do not change the subject line or your email may be missed.  Clearly mention your shipping address with phone number and pin/zip code. Send your receipt before Oct 30, 2012. We will not entertain any conversation after Oct 30, 2012 cut off date. The Free books will be sent to USA and India address only. Availability USA - Amazon | India - Flipkart | Indiaplaza Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Joes 2 Pros, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Book Review, SQLServer, T SQL, Technology

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  • Silverlight Recruiting Application Part 5 - Jobs Module / View

    Now we starting getting into a more code-heavy portion of this series, thankfully though this means the groundwork is all set for the most part and after adding the modules we will have a complete application that can be provided with full source. The Jobs module will have two concerns- adding and maintaining jobs that can then be broadcast out to the website. How they are displayed on the site will be handled by our admin system (which will just poll from this common database), so we aren't too concerned with that, but rather with getting the information into the system and allowing the backend administration/HR users to keep things up to date. Since there is a fair bit of information that we want to display, we're going to move editing to a separate view so we can get all that information in an easy-to-use spot. With all the files created for this module, the project looks something like this: And now... on to the code. XAML for the Job Posting View All we really need for the Job Posting View is a RadGridView and a few buttons. This will let us both show off records and perform operations on the records without much hassle. That XAML is going to look something like this: 01.<Grid x:Name="LayoutRoot" 02.Background="White"> 03.<Grid.RowDefinitions> 04.<RowDefinition Height="30" /> 05.<RowDefinition /> 06.</Grid.RowDefinitions> 07.<StackPanel Orientation="Horizontal"> 08.<Button x:Name="xAddRecordButton" 09.Content="Add Job" 10.Width="120" 11.cal:Click.Command="{Binding AddRecord}" 12.telerik:StyleManager.Theme="Windows7" /> 13.<Button x:Name="xEditRecordButton" 14.Content="Edit Job" 15.Width="120" 16.cal:Click.Command="{Binding EditRecord}" 17.telerik:StyleManager.Theme="Windows7" /> 18.</StackPanel> 19.<telerikGrid:RadGridView x:Name="xJobsGrid" 20.Grid.Row="1" 21.IsReadOnly="True" 22.AutoGenerateColumns="False" 23.ColumnWidth="*" 24.RowDetailsVisibilityMode="VisibleWhenSelected" 25.ItemsSource="{Binding MyJobs}" 26.SelectedItem="{Binding SelectedJob, Mode=TwoWay}" 27.command:SelectedItemChangedEventClass.Command="{Binding SelectedItemChanged}"> 28.<telerikGrid:RadGridView.Columns> 29.<telerikGrid:GridViewDataColumn Header="Job Title" 30.DataMemberBinding="{Binding JobTitle}" 31.UniqueName="JobTitle" /> 32.<telerikGrid:GridViewDataColumn Header="Location" 33.DataMemberBinding="{Binding Location}" 34.UniqueName="Location" /> 35.<telerikGrid:GridViewDataColumn Header="Resume Required" 36.DataMemberBinding="{Binding NeedsResume}" 37.UniqueName="NeedsResume" /> 38.<telerikGrid:GridViewDataColumn Header="CV Required" 39.DataMemberBinding="{Binding NeedsCV}" 40.UniqueName="NeedsCV" /> 41.<telerikGrid:GridViewDataColumn Header="Overview Required" 42.DataMemberBinding="{Binding NeedsOverview}" 43.UniqueName="NeedsOverview" /> 44.<telerikGrid:GridViewDataColumn Header="Active" 45.DataMemberBinding="{Binding IsActive}" 46.UniqueName="IsActive" /> 47.</telerikGrid:RadGridView.Columns> 48.</telerikGrid:RadGridView> 49.</Grid> I'll explain what's happening here by line numbers: Lines 11 and 16: Using the same type of click commands as we saw in the Menu module, we tie the button clicks to delegate commands in the viewmodel. Line 25: The source for the jobs will be a collection in the viewmodel. Line 26: We also bind the selected item to a public property from the viewmodel for use in code. Line 27: We've turned the event into a command so we can handle it via code in the viewmodel. So those first three probably make sense to you as far as Silverlight/WPF binding magic is concerned, but for line 27... This actually comes from something I read onDamien Schenkelman's blog back in the day for creating an attached behavior from any event. So, any time you see me using command:Whatever.Command, the backing for it is actually something like this: SelectedItemChangedEventBehavior.cs: 01.public class SelectedItemChangedEventBehavior : CommandBehaviorBase<Telerik.Windows.Controls.DataControl> 02.{ 03.public SelectedItemChangedEventBehavior(DataControl element) 04.: base(element) 05.{ 06.element.SelectionChanged += new EventHandler<SelectionChangeEventArgs>(element_SelectionChanged); 07.} 08.void element_SelectionChanged(object sender, SelectionChangeEventArgs e) 09.{ 10.// We'll only ever allow single selection, so will only need item index 0 11.base.CommandParameter = e.AddedItems[0]; 12.base.ExecuteCommand(); 13.} 14.} SelectedItemChangedEventClass.cs: 01.public class SelectedItemChangedEventClass 02.{ 03.#region The Command Stuff 04.public static ICommand GetCommand(DependencyObject obj) 05.{ 06.return (ICommand)obj.GetValue(CommandProperty); 07.} 08.public static void SetCommand(DependencyObject obj, ICommand value) 09.{ 10.obj.SetValue(CommandProperty, value); 11.} 12.public static readonly DependencyProperty CommandProperty = 13.DependencyProperty.RegisterAttached("Command", typeof(ICommand), 14.typeof(SelectedItemChangedEventClass), new PropertyMetadata(OnSetCommandCallback)); 15.public static void OnSetCommandCallback(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs e) 16.{ 17.DataControl element = dependencyObject as DataControl; 18.if (element != null) 19.{ 20.SelectedItemChangedEventBehavior behavior = GetOrCreateBehavior(element); 21.behavior.Command = e.NewValue as ICommand; 22.} 23.} 24.#endregion 25.public static SelectedItemChangedEventBehavior GetOrCreateBehavior(DataControl element) 26.{ 27.SelectedItemChangedEventBehavior behavior = element.GetValue(SelectedItemChangedEventBehaviorProperty) as SelectedItemChangedEventBehavior; 28.if (behavior == null) 29.{ 30.behavior = new SelectedItemChangedEventBehavior(element); 31.element.SetValue(SelectedItemChangedEventBehaviorProperty, behavior); 32.} 33.return behavior; 34.} 35.public static SelectedItemChangedEventBehavior GetSelectedItemChangedEventBehavior(DependencyObject obj) 36.{ 37.return (SelectedItemChangedEventBehavior)obj.GetValue(SelectedItemChangedEventBehaviorProperty); 38.} 39.public static void SetSelectedItemChangedEventBehavior(DependencyObject obj, SelectedItemChangedEventBehavior value) 40.{ 41.obj.SetValue(SelectedItemChangedEventBehaviorProperty, value); 42.} 43.public static readonly DependencyProperty SelectedItemChangedEventBehaviorProperty = 44.DependencyProperty.RegisterAttached("SelectedItemChangedEventBehavior", 45.typeof(SelectedItemChangedEventBehavior), typeof(SelectedItemChangedEventClass), null); 46.} These end up looking very similar from command to command, but in a nutshell you create a command based on any event, determine what the parameter for it will be, then execute. It attaches via XAML and ties to a DelegateCommand in the viewmodel, so you get the full event experience (since some controls get a bit event-rich for added functionality). Simple enough, right? Viewmodel for the Job Posting View The Viewmodel is going to need to handle all events going back and forth, maintaining interactions with the data we are using, and both publishing and subscribing to events. Rather than breaking this into tons of little pieces, I'll give you a nice view of the entire viewmodel and then hit up the important points line-by-line: 001.public class JobPostingViewModel : ViewModelBase 002.{ 003.private readonly IEventAggregator eventAggregator; 004.private readonly IRegionManager regionManager; 005.public DelegateCommand<object> AddRecord { get; set; } 006.public DelegateCommand<object> EditRecord { get; set; } 007.public DelegateCommand<object> SelectedItemChanged { get; set; } 008.public RecruitingContext context; 009.private QueryableCollectionView _myJobs; 010.public QueryableCollectionView MyJobs 011.{ 012.get { return _myJobs; } 013.} 014.private QueryableCollectionView _selectionJobActionHistory; 015.public QueryableCollectionView SelectedJobActionHistory 016.{ 017.get { return _selectionJobActionHistory; } 018.} 019.private JobPosting _selectedJob; 020.public JobPosting SelectedJob 021.{ 022.get { return _selectedJob; } 023.set 024.{ 025.if (value != _selectedJob) 026.{ 027._selectedJob = value; 028.NotifyChanged("SelectedJob"); 029.} 030.} 031.} 032.public SubscriptionToken editToken = new SubscriptionToken(); 033.public SubscriptionToken addToken = new SubscriptionToken(); 034.public JobPostingViewModel(IEventAggregator eventAgg, IRegionManager regionmanager) 035.{ 036.// set Unity items 037.this.eventAggregator = eventAgg; 038.this.regionManager = regionmanager; 039.// load our context 040.context = new RecruitingContext(); 041.this._myJobs = new QueryableCollectionView(context.JobPostings); 042.context.Load(context.GetJobPostingsQuery()); 043.// set command events 044.this.AddRecord = new DelegateCommand<object>(this.AddNewRecord); 045.this.EditRecord = new DelegateCommand<object>(this.EditExistingRecord); 046.this.SelectedItemChanged = new DelegateCommand<object>(this.SelectedRecordChanged); 047.SetSubscriptions(); 048.} 049.#region DelegateCommands from View 050.public void AddNewRecord(object obj) 051.{ 052.this.eventAggregator.GetEvent<AddJobEvent>().Publish(true); 053.} 054.public void EditExistingRecord(object obj) 055.{ 056.if (_selectedJob == null) 057.{ 058.this.eventAggregator.GetEvent<NotifyUserEvent>().Publish("No job selected."); 059.} 060.else 061.{ 062.this._myJobs.EditItem(this._selectedJob); 063.this.eventAggregator.GetEvent<EditJobEvent>().Publish(this._selectedJob); 064.} 065.} 066.public void SelectedRecordChanged(object obj) 067.{ 068.if (obj.GetType() == typeof(ActionHistory)) 069.{ 070.// event bubbles up so we don't catch items from the ActionHistory grid 071.} 072.else 073.{ 074.JobPosting job = obj as JobPosting; 075.GrabHistory(job.PostingID); 076.} 077.} 078.#endregion 079.#region Subscription Declaration and Events 080.public void SetSubscriptions() 081.{ 082.EditJobCompleteEvent editComplete = eventAggregator.GetEvent<EditJobCompleteEvent>(); 083.if (editToken != null) 084.editComplete.Unsubscribe(editToken); 085.editToken = editComplete.Subscribe(this.EditCompleteEventHandler); 086.AddJobCompleteEvent addComplete = eventAggregator.GetEvent<AddJobCompleteEvent>(); 087.if (addToken != null) 088.addComplete.Unsubscribe(addToken); 089.addToken = addComplete.Subscribe(this.AddCompleteEventHandler); 090.} 091.public void EditCompleteEventHandler(bool complete) 092.{ 093.if (complete) 094.{ 095.JobPosting thisJob = _myJobs.CurrentEditItem as JobPosting; 096.this._myJobs.CommitEdit(); 097.this.context.SubmitChanges((s) => 098.{ 099.ActionHistory myAction = new ActionHistory(); 100.myAction.PostingID = thisJob.PostingID; 101.myAction.Description = String.Format("Job '{0}' has been edited by {1}", thisJob.JobTitle, "default user"); 102.myAction.TimeStamp = DateTime.Now; 103.eventAggregator.GetEvent<AddActionEvent>().Publish(myAction); 104.} 105., null); 106.} 107.else 108.{ 109.this._myJobs.CancelEdit(); 110.} 111.this.MakeMeActive(this.regionManager, "MainRegion", "JobPostingsView"); 112.} 113.public void AddCompleteEventHandler(JobPosting job) 114.{ 115.if (job == null) 116.{ 117.// do nothing, new job add cancelled 118.} 119.else 120.{ 121.this.context.JobPostings.Add(job); 122.this.context.SubmitChanges((s) => 123.{ 124.ActionHistory myAction = new ActionHistory(); 125.myAction.PostingID = job.PostingID; 126.myAction.Description = String.Format("Job '{0}' has been added by {1}", job.JobTitle, "default user"); 127.myAction.TimeStamp = DateTime.Now; 128.eventAggregator.GetEvent<AddActionEvent>().Publish(myAction); 129.} 130., null); 131.} 132.this.MakeMeActive(this.regionManager, "MainRegion", "JobPostingsView"); 133.} 134.#endregion 135.public void GrabHistory(int postID) 136.{ 137.context.ActionHistories.Clear(); 138._selectionJobActionHistory = new QueryableCollectionView(context.ActionHistories); 139.context.Load(context.GetHistoryForJobQuery(postID)); 140.} Taking it from the top, we're injecting an Event Aggregator and Region Manager for use down the road and also have the public DelegateCommands (just like in the Menu module). We also grab a reference to our context, which we'll obviously need for data, then set up a few fields with public properties tied to them. We're also setting subscription tokens, which we have not yet seen but I will get into below. The AddNewRecord (50) and EditExistingRecord (54) methods should speak for themselves for functionality, the one thing of note is we're sending events off to the Event Aggregator which some module, somewhere will take care of. Since these aren't entirely relying on one another, the Jobs View doesn't care if anyone is listening, but it will publish AddJobEvent (52), NotifyUserEvent (58) and EditJobEvent (63)regardless. Don't mind the GrabHistory() method so much, that is just grabbing history items (visibly being created in the SubmitChanges callbacks), and adding them to the database. Every action will trigger a history event, so we'll know who modified what and when, just in case. ;) So where are we at? Well, if we click to Add a job, we publish an event, if we edit a job, we publish an event with the selected record (attained through the magic of binding). Where is this all going though? To the Viewmodel, of course! XAML for the AddEditJobView This is pretty straightforward except for one thing, noted below: 001.<Grid x:Name="LayoutRoot" 002.Background="White"> 003.<Grid x:Name="xEditGrid" 004.Margin="10" 005.validationHelper:ValidationScope.Errors="{Binding Errors}"> 006.<Grid.Background> 007.<LinearGradientBrush EndPoint="0.5,1" 008.StartPoint="0.5,0"> 009.<GradientStop Color="#FFC7C7C7" 010.Offset="0" /> 011.<GradientStop Color="#FFF6F3F3" 012.Offset="1" /> 013.</LinearGradientBrush> 014.</Grid.Background> 015.<Grid.RowDefinitions> 016.<RowDefinition Height="40" /> 017.<RowDefinition Height="40" /> 018.<RowDefinition Height="40" /> 019.<RowDefinition Height="100" /> 020.<RowDefinition Height="100" /> 021.<RowDefinition Height="100" /> 022.<RowDefinition Height="40" /> 023.<RowDefinition Height="40" /> 024.<RowDefinition Height="40" /> 025.</Grid.RowDefinitions> 026.<Grid.ColumnDefinitions> 027.<ColumnDefinition Width="150" /> 028.<ColumnDefinition Width="150" /> 029.<ColumnDefinition Width="300" /> 030.<ColumnDefinition Width="100" /> 031.</Grid.ColumnDefinitions> 032.<!-- Title --> 033.<TextBlock Margin="8" 034.Text="{Binding AddEditString}" 035.TextWrapping="Wrap" 036.Grid.Column="1" 037.Grid.ColumnSpan="2" 038.FontSize="16" /> 039.<!-- Data entry area--> 040. 041.<TextBlock Margin="8,0,0,0" 042.Style="{StaticResource LabelTxb}" 043.Grid.Row="1" 044.Text="Job Title" 045.VerticalAlignment="Center" /> 046.<TextBox x:Name="xJobTitleTB" 047.Margin="0,8" 048.Grid.Column="1" 049.Grid.Row="1" 050.Text="{Binding activeJob.JobTitle, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}" 051.Grid.ColumnSpan="2" /> 052.<TextBlock Margin="8,0,0,0" 053.Grid.Row="2" 054.Text="Location" 055.d:LayoutOverrides="Height" 056.VerticalAlignment="Center" /> 057.<TextBox x:Name="xLocationTB" 058.Margin="0,8" 059.Grid.Column="1" 060.Grid.Row="2" 061.Text="{Binding activeJob.Location, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}" 062.Grid.ColumnSpan="2" /> 063. 064.<TextBlock Margin="8,11,8,0" 065.Grid.Row="3" 066.Text="Description" 067.TextWrapping="Wrap" 068.VerticalAlignment="Top" /> 069. 070.<TextBox x:Name="xDescriptionTB" 071.Height="84" 072.TextWrapping="Wrap" 073.ScrollViewer.VerticalScrollBarVisibility="Auto" 074.Grid.Column="1" 075.Grid.Row="3" 076.Text="{Binding activeJob.Description, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}" 077.Grid.ColumnSpan="2" /> 078.<TextBlock Margin="8,11,8,0" 079.Grid.Row="4" 080.Text="Requirements" 081.TextWrapping="Wrap" 082.VerticalAlignment="Top" /> 083. 084.<TextBox x:Name="xRequirementsTB" 085.Height="84" 086.TextWrapping="Wrap" 087.ScrollViewer.VerticalScrollBarVisibility="Auto" 088.Grid.Column="1" 089.Grid.Row="4" 090.Text="{Binding activeJob.Requirements, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}" 091.Grid.ColumnSpan="2" /> 092.<TextBlock Margin="8,11,8,0" 093.Grid.Row="5" 094.Text="Qualifications" 095.TextWrapping="Wrap" 096.VerticalAlignment="Top" /> 097. 098.<TextBox x:Name="xQualificationsTB" 099.Height="84" 100.TextWrapping="Wrap" 101.ScrollViewer.VerticalScrollBarVisibility="Auto" 102.Grid.Column="1" 103.Grid.Row="5" 104.Text="{Binding activeJob.Qualifications, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}" 105.Grid.ColumnSpan="2" /> 106.<!-- Requirements Checkboxes--> 107. 108.<CheckBox x:Name="xResumeRequiredCB" Margin="8,8,8,15" 109.Content="Resume Required" 110.Grid.Row="6" 111.Grid.ColumnSpan="2" 112.IsChecked="{Binding activeJob.NeedsResume, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}"/> 113. 114.<CheckBox x:Name="xCoverletterRequiredCB" Margin="8,8,8,15" 115.Content="Cover Letter Required" 116.Grid.Column="2" 117.Grid.Row="6" 118.IsChecked="{Binding activeJob.NeedsCV, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}"/> 119. 120.<CheckBox x:Name="xOverviewRequiredCB" Margin="8,8,8,15" 121.Content="Overview Required" 122.Grid.Row="7" 123.Grid.ColumnSpan="2" 124.IsChecked="{Binding activeJob.NeedsOverview, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}"/> 125. 126.<CheckBox x:Name="xJobActiveCB" Margin="8,8,8,15" 127.Content="Job is Active" 128.Grid.Column="2" 129.Grid.Row="7" 130.IsChecked="{Binding activeJob.IsActive, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}"/> 131. 132.<!-- Buttons --> 133. 134.<Button x:Name="xAddEditButton" Margin="8,8,0,10" 135.Content="{Binding AddEditButtonString}" 136.cal:Click.Command="{Binding AddEditCommand}" 137.Grid.Column="2" 138.Grid.Row="8" 139.HorizontalAlignment="Left" 140.Width="125" 141.telerik:StyleManager.Theme="Windows7" /> 142. 143.<Button x:Name="xCancelButton" HorizontalAlignment="Right" 144.Content="Cancel" 145.cal:Click.Command="{Binding CancelCommand}" 146.Margin="0,8,8,10" 147.Width="125" 148.Grid.Column="2" 149.Grid.Row="8" 150.telerik:StyleManager.Theme="Windows7" /> 151.</Grid> 152.</Grid> The 'validationHelper:ValidationScope' line may seem odd. This is a handy little trick for catching current and would-be validation errors when working in this whole setup. This all comes from an approach found on theJoy Of Code blog, although it looks like the story for this will be changing slightly with new advances in SL4/WCF RIA Services, so this section can definitely get an overhaul a little down the road. The code is the fun part of all this, so let us see what's happening under the hood. Viewmodel for the AddEditJobView We are going to see some of the same things happening here, so I'll skip over the repeat info and get right to the good stuff: 001.public class AddEditJobViewModel : ViewModelBase 002.{ 003.private readonly IEventAggregator eventAggregator; 004.private readonly IRegionManager regionManager; 005. 006.public RecruitingContext context; 007. 008.private JobPosting _activeJob; 009.public JobPosting activeJob 010.{ 011.get { return _activeJob; } 012.set 013.{ 014.if (_activeJob != value) 015.{ 016._activeJob = value; 017.NotifyChanged("activeJob"); 018.} 019.} 020.} 021. 022.public bool isNewJob; 023. 024.private string _addEditString; 025.public string AddEditString 026.{ 027.get { return _addEditString; } 028.set 029.{ 030.if (_addEditString != value) 031.{ 032._addEditString = value; 033.NotifyChanged("AddEditString"); 034.} 035.} 036.} 037. 038.private string _addEditButtonString; 039.public string AddEditButtonString 040.{ 041.get { return _addEditButtonString; } 042.set 043.{ 044.if (_addEditButtonString != value) 045.{ 046._addEditButtonString = value; 047.NotifyChanged("AddEditButtonString"); 048.} 049.} 050.} 051. 052.public SubscriptionToken addJobToken = new SubscriptionToken(); 053.public SubscriptionToken editJobToken = new SubscriptionToken(); 054. 055.public DelegateCommand<object> AddEditCommand { get; set; } 056.public DelegateCommand<object> CancelCommand { get; set; } 057. 058.private ObservableCollection<ValidationError> _errors = new ObservableCollection<ValidationError>(); 059.public ObservableCollection<ValidationError> Errors 060.{ 061.get { return _errors; } 062.} 063. 064.private ObservableCollection<ValidationResult> _valResults = new ObservableCollection<ValidationResult>(); 065.public ObservableCollection<ValidationResult> ValResults 066.{ 067.get { return this._valResults; } 068.} 069. 070.public AddEditJobViewModel(IEventAggregator eventAgg, IRegionManager regionmanager) 071.{ 072.// set Unity items 073.this.eventAggregator = eventAgg; 074.this.regionManager = regionmanager; 075. 076.context = new RecruitingContext(); 077. 078.AddEditCommand = new DelegateCommand<object>(this.AddEditJobCommand); 079.CancelCommand = new DelegateCommand<object>(this.CancelAddEditCommand); 080. 081.SetSubscriptions(); 082.} 083. 084.#region Subscription Declaration and Events 085. 086.public void SetSubscriptions() 087.{ 088.AddJobEvent addJob = this.eventAggregator.GetEvent<AddJobEvent>(); 089. 090.if (addJobToken != null) 091.addJob.Unsubscribe(addJobToken); 092. 093.addJobToken = addJob.Subscribe(this.AddJobEventHandler); 094. 095.EditJobEvent editJob = this.eventAggregator.GetEvent<EditJobEvent>(); 096. 097.if (editJobToken != null) 098.editJob.Unsubscribe(editJobToken); 099. 100.editJobToken = editJob.Subscribe(this.EditJobEventHandler); 101.} 102. 103.public void AddJobEventHandler(bool isNew) 104.{ 105.this.activeJob = null; 106.this.activeJob = new JobPosting(); 107.this.activeJob.IsActive = true; // We assume that we want a new job to go up immediately 108.this.isNewJob = true; 109.this.AddEditString = "Add New Job Posting"; 110.this.AddEditButtonString = "Add Job"; 111. 112.MakeMeActive(this.regionManager, "MainRegion", "AddEditJobView"); 113.} 114. 115.public void EditJobEventHandler(JobPosting editJob) 116.{ 117.this.activeJob = null; 118.this.activeJob = editJob; 119.this.isNewJob = false; 120.this.AddEditString = "Edit Job Posting"; 121.this.AddEditButtonString = "Edit Job"; 122. 123.MakeMeActive(this.regionManager, "MainRegion", "AddEditJobView"); 124.} 125. 126.#endregion 127. 128.#region DelegateCommands from View 129. 130.public void AddEditJobCommand(object obj) 131.{ 132.if (this.Errors.Count > 0) 133.{ 134.List<string> errorMessages = new List<string>(); 135. 136.foreach (var valR in this.Errors) 137.{ 138.errorMessages.Add(valR.Exception.Message); 139.} 140. 141.this.eventAggregator.GetEvent<DisplayValidationErrorsEvent>().Publish(errorMessages); 142. 143.} 144.else if (!Validator.TryValidateObject(this.activeJob, new ValidationContext(this.activeJob, null, null), _valResults, true)) 145.{ 146.List<string> errorMessages = new List<string>(); 147. 148.foreach (var valR in this._valResults) 149.{ 150.errorMessages.Add(valR.ErrorMessage); 151.} 152. 153.this._valResults.Clear(); 154. 155.this.eventAggregator.GetEvent<DisplayValidationErrorsEvent>().Publish(errorMessages); 156.} 157.else 158.{ 159.if (this.isNewJob) 160.{ 161.this.eventAggregator.GetEvent<AddJobCompleteEvent>().Publish(this.activeJob); 162.} 163.else 164.{ 165.this.eventAggregator.GetEvent<EditJobCompleteEvent>().Publish(true); 166.} 167.} 168.} 169. 170.public void CancelAddEditCommand(object obj) 171.{ 172.if (this.isNewJob) 173.{ 174.this.eventAggregator.GetEvent<AddJobCompleteEvent>().Publish(null); 175.} 176.else 177.{ 178.this.eventAggregator.GetEvent<EditJobCompleteEvent>().Publish(false); 179.} 180.} 181. 182.#endregion 183.} 184.} We start seeing something new on line 103- the AddJobEventHandler will create a new job and set that to the activeJob item on the ViewModel. When this is all set, the view calls that familiar MakeMeActive method to activate itself. I made a bit of a management call on making views self-activate like this, but I figured it works for one reason. As I create this application, views may not exist that I have in mind, so after a view receives its 'ping' from being subscribed to an event, it prepares whatever it needs to do and then goes active. This way if I don't have 'edit' hooked up, I can click as the day is long on the main view and won't get lost in an empty region. Total personal preference here. :) Everything else should again be pretty straightforward, although I do a bit of validation checking in the AddEditJobCommand, which can either fire off an event back to the main view/viewmodel if everything is a success or sent a list of errors to our notification module, which pops open a RadWindow with the alerts if any exist. As a bonus side note, here's what my WCF RIA Services metadata looks like for handling all of the validation: private JobPostingMetadata() { } [StringLength(2500, ErrorMessage = "Description should be more than one and less than 2500 characters.", MinimumLength = 1)] [Required(ErrorMessage = "Description is required.")] public string Description; [Required(ErrorMessage="Active Status is Required")] public bool IsActive; [StringLength(100, ErrorMessage = "Posting title must be more than 3 but less than 100 characters.", MinimumLength = 3)] [Required(ErrorMessage = "Job Title is required.")] public bool JobTitle; [Required] public string Location; public bool NeedsCV; public bool NeedsOverview; public bool NeedsResume; public int PostingID; [Required(ErrorMessage="Qualifications are required.")] [StringLength(2500, ErrorMessage="Qualifications should be more than one and less than 2500 characters.", MinimumLength=1)] public string Qualifications; [StringLength(2500, ErrorMessage = "Requirements should be more than one and less than 2500 characters.", MinimumLength = 1)] [Required(ErrorMessage="Requirements are required.")] public string Requirements;   The RecruitCB Alternative See all that Xaml I pasted above? Those are now two pieces sitting in the JobsView.xaml file now. The only real difference is that the xEditGrid now sits in the same place as xJobsGrid, with visibility swapping out between the two for a quick switch. I also took out all the cal: and command: command references and replaced Button events with clicks and the Grid selection command replaced with a SelectedItemChanged event. Also, at the bottom of the xEditGrid after the last button, I add a ValidationSummary (with Visibility=Collapsed) to catch any errors that are popping up. Simple as can be, and leads to this being the single code-behind file: 001.public partial class JobsView : UserControl 002.{ 003.public RecruitingContext context; 004.public JobPosting activeJob; 005.public bool isNew; 006.private ObservableCollection<ValidationResult> _valResults = new ObservableCollection<ValidationResult>(); 007.public ObservableCollection<ValidationResult> ValResults 008.{ 009.get { return this._valResults; } 010.} 011.public JobsView() 012.{ 013.InitializeComponent(); 014.this.Loaded += new RoutedEventHandler(JobsView_Loaded); 015.} 016.void JobsView_Loaded(object sender, RoutedEventArgs e) 017.{ 018.context = new RecruitingContext(); 019.xJobsGrid.ItemsSource = context.JobPostings; 020.context.Load(context.GetJobPostingsQuery()); 021.} 022.private void xAddRecordButton_Click(object sender, RoutedEventArgs e) 023.{ 024.activeJob = new JobPosting(); 025.isNew = true; 026.xAddEditTitle.Text = "Add a Job Posting"; 027.xAddEditButton.Content = "Add"; 028.xEditGrid.DataContext = activeJob; 029.HideJobsGrid(); 030.} 031.private void xEditRecordButton_Click(object sender, RoutedEventArgs e) 032.{ 033.activeJob = xJobsGrid.SelectedItem as JobPosting; 034.isNew = false; 035.xAddEditTitle.Text = "Edit a Job Posting"; 036.xAddEditButton.Content = "Edit"; 037.xEditGrid.DataContext = activeJob; 038.HideJobsGrid(); 039.} 040.private void xAddEditButton_Click(object sender, RoutedEventArgs e) 041.{ 042.if (!Validator.TryValidateObject(this.activeJob, new ValidationContext(this.activeJob, null, null), _valResults, true)) 043.{ 044.List<string> errorMessages = new List<string>(); 045.foreach (var valR in this._valResults) 046.{ 047.errorMessages.Add(valR.ErrorMessage); 048.} 049.this._valResults.Clear(); 050.ShowErrors(errorMessages); 051.} 052.else if (xSummary.Errors.Count > 0) 053.{ 054.List<string> errorMessages = new List<string>(); 055.foreach (var err in xSummary.Errors) 056.{ 057.errorMessages.Add(err.Message); 058.} 059.ShowErrors(errorMessages); 060.} 061.else 062.{ 063.if (this.isNew) 064.{ 065.context.JobPostings.Add(activeJob); 066.context.SubmitChanges((s) => 067.{ 068.ActionHistory thisAction = new ActionHistory(); 069.thisAction.PostingID = activeJob.PostingID; 070.thisAction.Description = String.Format("Job '{0}' has been edited by {1}", activeJob.JobTitle, "default user"); 071.thisAction.TimeStamp = DateTime.Now; 072.context.ActionHistories.Add(thisAction); 073.context.SubmitChanges(); 074.}, null); 075.} 076.else 077.{ 078.context.SubmitChanges((s) => 079.{ 080.ActionHistory thisAction = new ActionHistory(); 081.thisAction.PostingID = activeJob.PostingID; 082.thisAction.Description = String.Format("Job '{0}' has been added by {1}", activeJob.JobTitle, "default user"); 083.thisAction.TimeStamp = DateTime.Now; 084.context.ActionHistories.Add(thisAction); 085.context.SubmitChanges(); 086.}, null); 087.} 088.ShowJobsGrid(); 089.} 090.} 091.private void xCancelButton_Click(object sender, RoutedEventArgs e) 092.{ 093.ShowJobsGrid(); 094.} 095.private void ShowJobsGrid() 096.{ 097.xAddEditRecordButtonPanel.Visibility = Visibility.Visible; 098.xEditGrid.Visibility = Visibility.Collapsed; 099.xJobsGrid.Visibility = Visibility.Visible; 100.} 101.private void HideJobsGrid() 102.{ 103.xAddEditRecordButtonPanel.Visibility = Visibility.Collapsed; 104.xJobsGrid.Visibility = Visibility.Collapsed; 105.xEditGrid.Visibility = Visibility.Visible; 106.} 107.private void ShowErrors(List<string> errorList) 108.{ 109.string nm = "Errors received: \n"; 110.foreach (string anerror in errorList) 111.nm += anerror + "\n"; 112.RadWindow.Alert(nm); 113.} 114.} The first 39 lines should be pretty familiar, not doing anything too unorthodox to get this up and running. Once we hit the xAddEditButton_Click on line 40, we're still doing pretty much the same things except instead of checking the ValidationHelper errors, we both run a check on the current activeJob object as well as check the ValidationSummary errors list. Once that is set, we again use the callback of context.SubmitChanges (lines 68 and 78) to create an ActionHistory which we will use to track these items down the line. That's all? Essentially... yes. If you look back through this post, most of the code and adventures we have taken were just to get things working in the MVVM/Prism setup. Since I have the whole 'module' self-contained in a single JobView+code-behind setup, I don't have to worry about things like sending events off into space for someone to pick up, communicating through an Infrastructure project, or even re-inventing events to be used with attached behaviors. Everything just kinda works, and again with much less code. Here's a picture of the MVVM and Code-behind versions on the Jobs and AddEdit views, but since the functionality is the same in both apps you still cannot tell them apart (for two-strike): Looking ahead, the Applicants module is effectively the same thing as the Jobs module, so most of the code is being cut-and-pasted back and forth with minor tweaks here and there. So that one is being taken care of by me behind the scenes. Next time, we get into a new world of fun- the interview scheduling module, which will pull from available jobs and applicants for each interview being scheduled, tying everything together with RadScheduler to the rescue. Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Rendering Linear Gradients using the HTML5 Canvas

    - by dwahlin
    Related HTML5 Canvas Posts: Getting Started with the HTML5 Canvas Rendering Text with the HTML5 Canvas Creating a Line Chart using the HTML5 Canvas New Pluralsight Course: HTML5 Canvas Fundamentals Gradients are everywhere. They’re used to enhance toolbars or buttons and help add additional flare to a web page when used appropriately. In the past we’ve always had to rely on images to render gradients which works well, but isn’t necessarily the most efficient (although 1 pixel wide images do work well). CSS3 provides a great way to render gradients in modern browsers (see http://www.colorzilla.com/gradient-editor for a nice online gradient generator tool) but it’s not the only option. If you’re working with charts, games, multimedia or other HTML5 Canvas applications you can also use gradients and render them on the client-side without relying on images. In this post I’ll introduce how to use linear gradients and discuss the different functions that can be used to create them.   Creating Linear Gradients Linear gradients can be created using the 2D context’s createLinearGradient function. The function takes the starting x,y coordinates and ending x,y coordinates of the gradient:   createLinearGradient(x1, y1, x2, y2);   By changing the start and end coordinates you can control the direction that the gradient renders. For example, adding the following coordinates causes the gradient to render from left to right since the y value stays at 0 for both points while the x value changes from 0 to 200. var lgrad = ctx.createLinearGradient(0, 0, 200, 0); Here’s an example of how changing the coordinates affects the gradient direction:   Once a linear gradient object has been created you can set color stops using the addColorStop() function. It takes the location where the color should appear in the gradient with 0 being the beginning and 1 being at the end (0.5 would be in the middle) as well as the color to display in the gradient. lgrad.addColorStop(0, 'white'); lgrad.addColorStop(1, 'gray');   An example of combining createLinearGradient() with addColorStop() is shown next:   Using createLinearGradient() var canvas = document.getElementById('myCanvas'); var ctx = canvas.getContext('2d'); var lgrad = ctx.createLinearGradient(0, 0, 200, 0); lgrad.addColorStop(0, 'white'); lgrad.addColorStop(1, 'gray'); ctx.fillStyle = lgrad; ctx.fillRect(0, 0, 200, 200); ctx.strokeRect(0, 0, 200, 200); This code renders a white to gray gradient as shown next: A live example of using createLinearGradient() is shown next. Click the Result tab to see the code in action.   In the next post on the HTML5 Canvas I’ll take a look at radial gradients and how they can be used. In the meantime, if you’re interested in learning more about the HTML5 Canvas and how it can be used in your Web or Windows 8 applications, check out my HTML5 Canvas Fundamentals course from Pluralsight. It has over 4 1/2 hours of canvas goodness packed in it.

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  • Beginner Geek: Scan a Document or Picture in Windows 7

    - by Mysticgeek
    There may come a time when you want to digitize your priceless old pictures, or need to scan a receipts and documents for your company. Today we look at how to scan a picture or document in Windows 7. Scanning Your Document In this example we’re using an HP PSC 1500 All-In-One printer connected to a Windows 7 Home Premium 32-bit system. Different scanners will vary, however the process is essentially the same. The scanning process has changed a bit since the XP days. To scan a document in Windows 7, place the document or picture in the scanner, click on Start, and go to Devices and Printers.   When the Devices and Printers window opens, find your scanning device and double-click on it to get the manufacturers Printer Actions menu. For our HP PSC 1500 we have a few different options like printing, device setup, and scanner actions. Here we’ll click on the Scan a document or photo hyperlink. The New Scan window opens and from here you can adjust the quality of the scanned image and choose the output file type. Then click the Preview button to get an idea of what the image will look like.   If you’re not happy with the preview, then you can go back and make any adjustments to the quality of the document or photo. Once everything looks good, click on the Scan button. The scanning process will start. The amount of time it takes will depend on your scanner type, and the quality of the settings you choose. The higher the quality…the more time it will take. You will have the option to tag the picture if you want to… Now you can view your scanned document or photo inside Windows Photo Viewer. If you’re happy with the look of the document, you can send it off in an email, put it on an network drive, FTP it… whatever you need to do with it. Another method is to place the document of photo you wish to scan in the scanner, open up Devices and Printers, then right-click on the scanning device and select Start Scan from the context menu. This should bypass the manufacturer screen and go directly into the New Scan window, where you can start the scan process. From the Context Menu you can also choose Scan Properties. This will allow you to test the scanner if you’re having problems with it and change some of its settings. Or you can choose Scan Profiles which allows you to use pre-selected settings, create your own, or set one as the default. Although scanning documents and photos isn’t a common occurrence as it was a few years ago, Windows 7 still includes the feature. When you need to scan a document or photo in Windows 7, this should get you started. Similar Articles Productive Geek Tips Easily Rotate Pictures In Word 2007Beginner Geek: Delete User Accounts in Windows 7Customize Your Welcome Picture Choices in Windows VistaSecure Computing: Detect and Eliminate Malware Using Windows DefenderMark Your Document As Final in Word 2007 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips VMware Workstation 7 Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Creating a Password Reset Disk in Windows Bypass Waiting Time On Customer Service Calls With Lucyphone MELTUP – "The Beginning Of US Currency Crisis And Hyperinflation" Enable or Disable the Task Manager Using TaskMgrED Explorer++ is a Worthy Windows Explorer Alternative Error Goblin Explains Windows Error Codes

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  • What’s the use of code reuse?

    - by Tony Davis
    All great developers write reusable code, don’t they? Well, maybe, but as with all statements regarding what “great” developers do or don’t do, it’s probably an over-simplification. A novice programmer, in particular, will encounter in the literature a general assumption of the importance of code reusability. They spend time worrying about DRY (don’t repeat yourself), moving logic into specific “helper” modules that they can then reuse, agonizing about the minutiae of the class structure, inheritance and interface design that will promote easy reuse. Unfortunately, writing code specifically for reuse often leads to complicated object hierarchies and inheritance models that are anything but reusable. If, instead, one strives to write simple code units that are highly maintainable and perform a single function, in a concise, isolated fashion then the potential for reuse simply “drops out” as a natural by-product. Programmers, of course, care about these principles, about encapsulation and clean interfaces that don’t expose inner workings and allow easy pluggability. This is great when it helps with the maintenance and development of code but how often, in practice, do we actually reuse our code? Most DBAs and database developers are familiar with the practical reasons for the limited opportunities to reuse database code and its potential downsides. However, surely elsewhere in our code base, reuse happens often. After all, we can all name examples, such as date/time handling modules, which if we write with enough care we can plug in to many places. I spoke to a developer just yesterday who looked me in the eye and told me that in 30+ years as a developer (a successful one, I’d add), he’d never once reused his own code. As I sat blinking in disbelief, he explained that, of course, he always thought he would reuse it. He’d often agonized over its design, certain that he was creating code of great significance that he and other generations would reuse, with grateful tears misting their eyes. In fact, it never happened. He had in his head, most of the algorithms he needed and would simply write the code from scratch each time, refining the algorithms and tailoring the code to meet the specific requirements. It was, he said, simply quicker to do that than dig out the old code, check it, correct the mistakes, and adapt it. Is this a common experience, or just a strange anomaly? Viewed in a certain light, building code with a focus on reusability seems to hark to a past age where people built cars and music systems with the idea that someone else could and would replace and reuse the parts. Technology advances so rapidly that the next time you need the “same” code, it’s likely a new technique, or a whole new language, has emerged in the meantime, better equipped to tackle the task. Maybe we should be less fearful of the idea that we could write code well suited to the system requirements, but with little regard for reuse potential, and then rewrite a better version from scratch the next time.

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  • Best Practices for Handing over Legacy Code

    - by PersonalNexus
    In a couple of months a colleague will be moving on to a new project and I will be inheriting one of his projects. To prepare, I have already ordered Michael Feathers' Working Effectively with Legacy Code. But this books as well as most questions on legacy code I found so far are concerned with the case of inheriting code as-is. But in this case I actually have access to the original developer and we do have some time for an orderly hand-over. Some background on the piece of code I will be inheriting: It's functioning: There are no known bugs, but as performance requirements keep going up, some optimizations will become necessary in the not too distant future. Undocumented: There is pretty much zero documentation at the method and class level. What the code is supposed to do at a higher level, though, is well-understood, because I have been writing against its API (as a black-box) for years. Only higher-level integration tests: There are only integration tests testing proper interaction with other components via the API (again, black-box). Very low-level, optimized for speed: Because this code is central to an entire system of applications, a lot of it has been optimized several times over the years and is extremely low-level (one part has its own memory manager for certain structs/records). Concurrent and lock-free: While I am very familiar with concurrent and lock-free programming and have actually contributed a few pieces to this code, this adds another layer of complexity. Large codebase: This particular project is more than ten thousand lines of code, so there is no way I will be able to have everything explained to me. Written in Delphi: I'm just going to put this out there, although I don't believe the language to be germane to the question, as I believe this type of problem to be language-agnostic. I was wondering how the time until his departure would best be spent. Here are a couple of ideas: Get everything to build on my machine: Even though everything should be checked into source code control, who hasn't forgotten to check in a file once in a while, so this should probably be the first order of business. More tests: While I would like more class-level unit tests so that when I will be making changes, any bugs I introduce can be caught early on, the code as it is now is not testable (huge classes, long methods, too many mutual dependencies). What to document: I think for starters it would be best to focus documentation on those areas in the code that would otherwise be difficult to understand e.g. because of their low-level/highly optimized nature. I am afraid there are a couple of things in there that might look ugly and in need of refactoring/rewriting, but are actually optimizations that have been out in there for a good reason that I might miss (cf. Joel Spolsky, Things You Should Never Do, Part I) How to document: I think some class diagrams of the architecture and sequence diagrams of critical functions accompanied by some prose would be best. Who to document: I was wondering what would be better, to have him write the documentation or have him explain it to me, so I can write the documentation. I am afraid, that things that are obvious to him but not me would otherwise not be covered properly. Refactoring using pair-programming: This might not be possible to do due to time constraints, but maybe I could refactor some of his code to make it more maintainable while he was still around to provide input on why things are the way they are. Please comment on and add to this. Since there isn't enough time to do all of this, I am particularly interested in how you would prioritize.

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  • Visual Studio 2010 SP1

    - by ScottGu
    Last week we shipped Service Pack 1 of Visual Studio 2010 and the Visual Studio Express Tools.  In addition to bug fixes and performance improvements, SP1 includes a number of feature enhancements.  This includes improved local help support, IntelliTrace support for 64-bit applications and SharePoint, built-in Silverlight 4 Tooling support in the box, unit testing support when targeting .NET 3.5, a new performance wizard for Silverlight, IIS Express and SQL CE Tooling support for web projects, HTML5 Intellisense for ASP.NET, and more.  TFS 2010 SP1 was also released last week, together with a new TFS Project Server Integration Pack and Load Test Feature Pack.  Brian Harry has a good blog post about the TFS updates here. VS 2010 SP1 Download Click here to download and install SP1 for all versions of Visual Studio (including express).  This installer examines what you have installed on your machine, and only downloads the servicing downloads necessary to update them to SP1.  The time it takes to download and update will consequently depend on what all you have installed.  Jon Galloway has a good blog post on tips to speed up the SP1 install by uninstalling unused components. Web Platform Installer Bundles In addition to the core VS 2010 SP1 installer, we have also put together two Web Platform Installer (WebPI) bundles that automate installing SP1 together with additional web-specific components: VS 2010 SP1 WebPI Bundle Visual Web Developer 2010 SP1 WebPI Bundle The above WebPI bundles automate installing: VS 2010/VWD 2010 SP1 ASP.NET MVC 3 (runtime + tools support) IIS 7.5 Express SQL Server Compact Edition 4.0 (runtime + tools support) Web Deployment 2.0 Only the components that are not already installed on your machine will be downloaded when you use the above WebPI bundles.  This means that you can run the WebPI bundle at any time (even if you have already installed SP1 or ASP.NET MVC 3) and not have to worry about wasting time downloading/installing these components again. Earlier this year I did two posts that discussed how to use IIS Express and SQL CE with ASP.NET projects in SP1.  Read the below posts to learn more about how to use them after you run the above bundles: Visual Studio 2010 SP1 and IIS Express Visual Studio 2010 SP1 and SQL CE for ASP.NET The above feature additions work with any web project type – including both ASP.NET Web Forms and ASP.NET MVC. Additional SP1 Notes Two additional notes about VS 2010 SP1: 1) One change we made between RTM and SP1 is that by default Visual Studio now uses software rendering instead of hardware acceleration when running on Windows XP.  We made this change because we’ve seen reports of (often inconsistent) performance issues caused by older video drivers.  Running in software mode eliminates these and delivers consistent speeds.  You can optionally re-enable hardware acceleration with SP1 using Visual Studio’s Tools->Options menu command – we did not remove support for HW acceleration on XP, we simply changed the default setting for it.  Jason Zander has written more details on the change and how to re-enable HW acceleration inside VS here. 2) We have discovered an issue where installing SP1 can cause TSQL intellisense within SQL Server Management Studio 2008 R2 to stop working (typing still works – but intellisense doesn’t show up).  The SQL team is investigating this now and I’ll post an update on how to fix this once more details are known.  Hope this helps, Scott P.S. I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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  • Using the Katana Authentication handlers with NancyFx

    - by cibrax
    Once you write an OWIN Middleware service, it can be reused everywhere as long as OWIN is supported. In my last post, I discussed how you could write an Authentication Handler in Katana for Hawk (HMAC Authentication). Good news is NancyFx can be run as an OWIN handler, so you can use many of existing middleware services, including the ones that are ship with Katana. Running NancyFx as a OWIN handler is pretty straightforward, and discussed in detail as part of the NancyFx documentation here. After run the steps described there and you have the application working, only a few more steps are required to register the additional middleware services. The example bellow shows how the Startup class is modified to include Hawk authentication. public class Startup { public void Configuration(IAppBuilder app) { app.UseHawkAuthentication(new HawkAuthenticationOptions { Credentials = (id) => { return new HawkCredential { Id = "dh37fgj492je", Key = "werxhqb98rpaxn39848xrunpaw3489ruxnpa98w4rxn", Algorithm = "hmacsha256", User = "steve" }; } }); app.UseNancy(); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This code registers the Hawk Authentication Handler on top of the OWIN pipeline, so it will try to authenticate the calls before the request messages are passed over to NancyFx. The authentication handlers in Katana set the user principal in the OWIN environment using the key “server.User”. The following code shows how you can get that principal in a NancyFx module, public class HomeModule : NancyModule { public HomeModule() { Get["/"] = x => { var env = (IDictionary<string, object>)Context.Items[NancyOwinHost.RequestEnvironmentKey]; if (!env.ContainsKey("server.User") || env["server.User"] == null) { return HttpStatusCode.Unauthorized; } var identity = (ClaimsPrincipal)env["server.User"]; return "Hello " + identity.Identity.Name; }; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Thanks to OWIN, you don’t know any details of how these cross cutting concerns can be implemented in every possible web application framework.

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  • The New Social Developer Community: a Q&A

    - by Mike Stiles
    In our last blog, we introduced the opportunities that lie ahead for social developers as social applications reach across every aspect and function of the enterprise. Leading the upcoming JavaOne Social Developer Program October 2 at the San Francisco Hilton is Roland Smart, VP of Social Marketing at Oracle. I got to ask Roland a few of the questions an existing or budding social developer might want to know as social extends beyond interacting with friends and marketing and into the enterprise. Why is it smart for developers to specialize as social developers? What opportunities lie in the immediate future that’s making this a critical, in-demand position? Social has changed the way we interact with brands and with each other across the web. As we acclimate to a new social paradigm we also look to extend its benefits into new areas of our lives. The workplace is a logical next step, and we're starting to see social interactions more and more in this context. But unlocking the value of social interactions requires technical expertise and knowledge of developing social apps that tap into the social graph. Developers focused on integrating social experiences into enterprise applications must be familiar with popular social APIs and must understand how to build enterprise social graphs of their own. These developers are part of an emerging community of social developers and are key to socially enabling the enterprise. Facebook rebranded their Preferred Developer Consultant Group (PDC) and the Preferred Marketing Developers (PMD) to underscore the fact developers are required inside marketing organizations to unlock the full potential of their platform. While this trend is starting on the marketing side with marketing developers, this is just an extension of the social developer concept that will ultimately drive social across the enterprise. What are some of the various ways social will be making its way into every area of enterprise organizations? How will it be utilized and what kinds of applications are going to be needed to facilitate and maximize these changes? Check out Oracle’s vision for the social-enabled enterprise. It’s a high-level overview of how social will impact across the enterprise. For example: HR can leverage social in recruiting and retentionSales can leverage social as a prospecting toolMarketing can use social to gain market insightCustomer support can use social to leverage community support to improve customer satisfaction while reducing service costOperations can leverage social improve systems That’s only the beginning. Once sleeves get rolled up and social developers and innovators get to work, still more social functions will no doubt emerge. What makes Java one of, if not the most viable platform on which to build these new enterprise social applications? Java is certainly one of the best platforms on which to build social experiences because there’s such a large existing community of Java developers. This means you can affordably recruit talent, and it's possible to effectively solicit advice from the community through various means, including our new Social Developer Community. Beyond that, there are already some great proof points Java is the best platform for creating social experiences at scale. Consider LinkedIn and Twitter. Tell us more about the benefits of collaboration and more about what the Oracle Social Developer Community is. What opportunities does that offer up and what are some of the ways developers can actively participate in and benefit from that community? Much has been written about the overall benefits of collaborating with other developers. Those include an opportunity to introduce yourself to the community of social developers, foster a reputation, establish an expertise, contribute to the advancement of the space, get feedback, experiment with the latest concepts, and gain inspiration. In short, collaboration is a tool that must be applied properly within a framework to get the most value out of it. The OSDC is a place where social developers can congregate to discuss the opportunities/challenges of building social integrations into their applications. What “needs” will this community have? We don't know yet. But we wanted to create a forum where we can engage and understand what social developers are thinking about, excited about, struggling with, etc. The OSDL can then step in if we can help remove barriers and add value in a serious and committed way so Oracle can help drive practice development.

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  • Dynamic Class Inheritance For PHP

    - by VirtuosiMedia
    I have a situation where I think I might need dynamic class inheritance in PHP 5.3, but the idea doesn't sit well and I'm looking for a different design pattern to solve my problem if it's possible. Use Case I have a set of DB abstraction layer classes that dynamically compiles SQL queries, with one DAL class for each DB type (MySQL, MsSQL, Oracle, etc.). Each table in the database has its own class that extends the appropriate DAL class. The idea is that you interact with the table classes, but never directly use the DAL class. If you want to support a different DB type for your app, you don't need to rewrite any queries or even any code, you simply change a setting that swaps one DAL class out for another...and that's it. To give you a better idea of how this is used, you can take a look at the DAL class, the table classes, and how they are used on this StackExchange Code Review page. To really understand what I'm trying to do, please take a look at my implementation first before suggesting a solution. Issues The strategy that I had used previously was to have all of the DAL classes share the same class name. This eliminated autoloading, so I had to manually load the appropriate DAL class in a switch statement. However, this approach presents some problems for testing and documentation purposes, so I'd like to find a different way to solve the problem of loading the correct DAL class more elegantly. Update to clarify the issue The problem basically boils down to inconsistencies in the class name (pre-PHP 5.3) or class namespace (PHP 5.3) and its location in the directory structure. At this point, all of my DAL classes have the same name, DBObject, but reside in different folders, MySQL, Oracle, etc. My table classes all extend DBObject, but which DBObject they extend varies depending on which one has been loaded. Basically, I'm trying to have my cake and eat it too. The table classes act as a stable API and extend a dynamic backend, the DAL (DBObject) classes. It works great, but I outsmarted myself and because of the inconsistencies with the class names and their locations, I can't autoload the DBObject, which makes running unit tests and generating API docs impossible for the DBObject classes because the tests and docs rely on auto-loading. Just loading the appropriate DBObject into memory using a factory method won't work because there will be times when I need to load multiple DBObjects for testing. Because the classes currently share a name, this causes a class is already defined error. I can make exceptions for the DBObjects in my test code, obviously, but I'm looking for something a little less hacky as there may future instances where something similar would need to be done. Solutions? Worst case scenario, I can continue my current strategy, but I don't like it very much, especially as I'll soon be converting my code to PHP 5.3. I suspect that I can use some sort of dynamic inheritance via either namespaces (preferred) or a dynamic class extension, but I haven't been able to find good examples of this implemented in the wild. In your answers, please suggest either an alternate pattern that would work for this use case or an example of dynamic inheritance done right. Please assume PHP 5.3 with namespaced code. Any code examples are greatly encouraged. The preferred constraints for the solution are: DAL class can be autoloaded. DAL classes don't share the same exact same namespace, but share the same class name. As an example, I would prefer to use classes named DbObject that use namespaces like Vm\Db\MySql and Vm\Db\Oracle. Table classes don't have to be rewritten with a change in DB type. The appropriate DB type is determined via a single setting only. That setting is the only thing that should need to change to interchange DB types. Ideally, the setting check should occur only once per page load, but I'm flexible on that.

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  • Metro: Promises

    - by Stephen.Walther
    The goal of this blog entry is to describe the Promise class in the WinJS library. You can use promises whenever you need to perform an asynchronous operation such as retrieving data from a remote website or a file from the file system. Promises are used extensively in the WinJS library. Asynchronous Programming Some code executes immediately, some code requires time to complete or might never complete at all. For example, retrieving the value of a local variable is an immediate operation. Retrieving data from a remote website takes longer or might not complete at all. When an operation might take a long time to complete, you should write your code so that it executes asynchronously. Instead of waiting for an operation to complete, you should start the operation and then do something else until you receive a signal that the operation is complete. An analogy. Some telephone customer service lines require you to wait on hold – listening to really bad music – until a customer service representative is available. This is synchronous programming and very wasteful of your time. Some newer customer service lines enable you to enter your telephone number so the customer service representative can call you back when a customer representative becomes available. This approach is much less wasteful of your time because you can do useful things while waiting for the callback. There are several patterns that you can use to write code which executes asynchronously. The most popular pattern in JavaScript is the callback pattern. When you call a function which might take a long time to return a result, you pass a callback function to the function. For example, the following code (which uses jQuery) includes a function named getFlickrPhotos which returns photos from the Flickr website which match a set of tags (such as “dog” and “funny”): function getFlickrPhotos(tags, callback) { $.getJSON( "http://api.flickr.com/services/feeds/photos_public.gne?jsoncallback=?", { tags: tags, tagmode: "all", format: "json" }, function (data) { if (callback) { callback(data.items); } } ); } getFlickrPhotos("funny, dogs", function(data) { $.each(data, function(index, item) { console.log(item); }); }); The getFlickr() function includes a callback parameter. When you call the getFlickr() function, you pass a function to the callback parameter which gets executed when the getFlicker() function finishes retrieving the list of photos from the Flickr web service. In the code above, the callback function simply iterates through the results and writes each result to the console. Using callbacks is a natural way to perform asynchronous programming with JavaScript. Instead of waiting for an operation to complete, sitting there and listening to really bad music, you can get a callback when the operation is complete. Using Promises The CommonJS website defines a promise like this (http://wiki.commonjs.org/wiki/Promises): “Promises provide a well-defined interface for interacting with an object that represents the result of an action that is performed asynchronously, and may or may not be finished at any given point in time. By utilizing a standard interface, different components can return promises for asynchronous actions and consumers can utilize the promises in a predictable manner.” A promise provides a standard pattern for specifying callbacks. In the WinJS library, when you create a promise, you can specify three callbacks: a complete callback, a failure callback, and a progress callback. Promises are used extensively in the WinJS library. The methods in the animation library, the control library, and the binding library all use promises. For example, the xhr() method included in the WinJS base library returns a promise. The xhr() method wraps calls to the standard XmlHttpRequest object in a promise. The following code illustrates how you can use the xhr() method to perform an Ajax request which retrieves a file named Photos.txt: var options = { url: "/data/photos.txt" }; WinJS.xhr(options).then( function (xmlHttpRequest) { console.log("success"); var data = JSON.parse(xmlHttpRequest.responseText); console.log(data); }, function(xmlHttpRequest) { console.log("fail"); }, function(xmlHttpRequest) { console.log("progress"); } ) The WinJS.xhr() method returns a promise. The Promise class includes a then() method which accepts three callback functions: a complete callback, an error callback, and a progress callback: Promise.then(completeCallback, errorCallback, progressCallback) In the code above, three anonymous functions are passed to the then() method. The three callbacks simply write a message to the JavaScript Console. The complete callback also dumps all of the data retrieved from the photos.txt file. Creating Promises You can create your own promises by creating a new instance of the Promise class. The constructor for the Promise class requires a function which accepts three parameters: a complete, error, and progress function parameter. For example, the code below illustrates how you can create a method named wait10Seconds() which returns a promise. The progress function is called every second and the complete function is not called until 10 seconds have passed: (function () { "use strict"; var app = WinJS.Application; function wait10Seconds() { return new WinJS.Promise(function (complete, error, progress) { var seconds = 0; var intervalId = window.setInterval(function () { seconds++; progress(seconds); if (seconds > 9) { window.clearInterval(intervalId); complete(); } }, 1000); }); } app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { wait10Seconds().then( function () { console.log("complete") }, function () { console.log("error") }, function (seconds) { console.log("progress:" + seconds) } ); } } app.start(); })(); All of the work happens in the constructor function for the promise. The window.setInterval() method is used to execute code every second. Every second, the progress() callback method is called. If more than 10 seconds have passed then the complete() callback method is called and the clearInterval() method is called. When you execute the code above, you can see the output in the Visual Studio JavaScript Console. Creating a Timeout Promise In the previous section, we created a custom Promise which uses the window.setInterval() method to complete the promise after 10 seconds. We really did not need to create a custom promise because the Promise class already includes a static method for returning promises which complete after a certain interval. The code below illustrates how you can use the timeout() method. The timeout() method returns a promise which completes after a certain number of milliseconds. WinJS.Promise.timeout(3000).then( function(){console.log("complete")}, function(){console.log("error")}, function(){console.log("progress")} ); In the code above, the Promise completes after 3 seconds (3000 milliseconds). The Promise returned by the timeout() method does not support progress events. Therefore, the only message written to the console is the message “complete” after 10 seconds. Canceling Promises Some promises, but not all, support cancellation. When you cancel a promise, the promise’s error callback is executed. For example, the following code uses the WinJS.xhr() method to perform an Ajax request. However, immediately after the Ajax request is made, the request is cancelled. // Specify Ajax request options var options = { url: "/data/photos.txt" }; // Make the Ajax request var request = WinJS.xhr(options).then( function (xmlHttpRequest) { console.log("success"); }, function (xmlHttpRequest) { console.log("fail"); }, function (xmlHttpRequest) { console.log("progress"); } ); // Cancel the Ajax request request.cancel(); When you run the code above, the message “fail” is written to the Visual Studio JavaScript Console. Composing Promises You can build promises out of other promises. In other words, you can compose promises. There are two static methods of the Promise class which you can use to compose promises: the join() method and the any() method. When you join promises, a promise is complete when all of the joined promises are complete. When you use the any() method, a promise is complete when any of the promises complete. The following code illustrates how to use the join() method. A new promise is created out of two timeout promises. The new promise does not complete until both of the timeout promises complete: WinJS.Promise.join([WinJS.Promise.timeout(1000), WinJS.Promise.timeout(5000)]) .then(function () { console.log("complete"); }); The message “complete” will not be written to the JavaScript Console until both promises passed to the join() method completes. The message won’t be written for 5 seconds (5,000 milliseconds). The any() method completes when any promise passed to the any() method completes: WinJS.Promise.any([WinJS.Promise.timeout(1000), WinJS.Promise.timeout(5000)]) .then(function () { console.log("complete"); }); The code above writes the message “complete” to the JavaScript Console after 1 second (1,000 milliseconds). The message is written to the JavaScript console immediately after the first promise completes and before the second promise completes. Summary The goal of this blog entry was to describe WinJS promises. First, we discussed how promises enable you to easily write code which performs asynchronous actions. You learned how to use a promise when performing an Ajax request. Next, we discussed how you can create your own promises. You learned how to create a new promise by creating a constructor function with complete, error, and progress parameters. Finally, you learned about several advanced methods of promises. You learned how to use the timeout() method to create promises which complete after an interval of time. You also learned how to cancel promises and compose promises from other promises.

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  • SQL SERVER – Understanding XML – Contest Win Joes 2 Pros Combo (USD 198) – Day 5 of 5

    - by pinaldave
    August 2011 we ran a contest where every day we give away one book for an entire month. The contest had extreme success. Lots of people participated and lots of give away. I have received lots of questions if we are doing something similar this month. Absolutely, instead of running a contest a month long we are doing something more interesting. We are giving away USD 198 worth gift every day for this week. We are giving away Joes 2 Pros 5 Volumes (BOOK) SQL 2008 Development Certification Training Kit every day. One copy in India and One in USA. Total 2 of the giveaway (worth USD 198). All the gifts are sponsored from the Koenig Training Solution and Joes 2 Pros. The books are available here Amazon | Flipkart | Indiaplaza How to Win: Read the Question Read the Hints Answer the Quiz in Contact Form in following format Question Answer Name of the country (The contest is open for USA and India residents only) 2 Winners will be randomly selected announced on August 20th. Question of the Day: Is following XML a well formed XML Document? <?xml version=”1.0″?> <address> <firstname>Pinal</firstname> <lastname>Dave</lastname> <title>Founder</title> <company>SQLAuthority.com</company> </address> a) Yes b) No c) I do not know Query Hints: BIG HINT POST A common observation by people seeing an XML file for the first time is that it looks like just a bunch of data inside a text file. XML files are text-based documents, which makes them easy to read.  All of the data is literally spelled out in the document and relies on a just a few characters (<, >, =) to convey relationships and structure of the data.  XML files can be used by any commonly available text editor, like Notepad. Much like a book’s Table of Contents, your first glance at well-formed XML will tell you the subject matter of the data and its general structure. Hints appearing within the data help you to quickly identify the main theme (similar to book’s subject), its headers (similar to chapter titles or sections of a book), data elements (similar to a book’s characters or chief topics), and so forth. We’ll learn to recognize and use the structural “hints,” which are XML’s markup components (e.g., XML tags, root elements). The XML Raw and Auto modes are great for displaying data as all attributes or all elements – but not both at once. If you want your XML stream to have some of its data shown in attributes and some shown as elements, then you can use the XML Path mode. If you are using an XML Path stream, then by default all values will be shown as elements. However, it is possible to pick one or more elements to be shown with an attribute(s) as well. Additional Hints: I have previously discussed various concepts from SQL Server Joes 2 Pros Volume 5. SQL Joes 2 Pros Development Series – OpenXML Options SQL Joes 2 Pros Development Series – Preparing XML in Memory SQL Joes 2 Pros Development Series – Shredding XML SQL Joes 2 Pros Development Series – Using Root With Auto XML Mode SQL Joes 2 Pros Development Series – Using Root With Auto XML Mode SQL Joes 2 Pros Development Series – What is XML? SQL Joes 2 Pros Development Series – What is XML? – 2 Next Step: Answer the Quiz in Contact Form in following format Question - Answer Name of the country (The contest is open for USA and India) Bonus Winner Leave a comment with your favorite article from the “additional hints” section and you may be eligible for surprise gift. There is no country restriction for this Bonus Contest. Do mention why you liked it any particular blog post and I will announce the winner of the same along with the main contest. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Joes 2 Pros, PostADay, SQL, SQL Authority, SQL Puzzle, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • SQL SERVER – MSQL_XP – Wait Type – Day 20 of 28

    - by pinaldave
    In this blog post, I am going to discuss something from my field experience. While consultation, I have seen various wait typed, but one of my customers who has been using SQL Server for all his operations had an interesting issue with a particular wait type. Our customer had more than 100+ SQL Server instances running and the whole server had MSSQL_XP wait type as the most number of wait types. While running sp_who2 and other diagnosis queries, I could not immediately figure out what the issue was because the query with that kind of wait type was nowhere to be found. After a day of research, I was relieved that the solution was very easy to figure out. Let us continue discussing this wait type. From Book On-Line: ?MSQL_XP occurs when a task is waiting for an extended stored procedure to end. SQL Server uses this wait state to detect potential MARS application deadlocks. The wait stops when the extended stored procedure call ends. MSQL_XP Explanation: This wait type is created because of the extended stored procedure. Extended Stored Procedures are executed within SQL Server; however, SQL Server has no control over them. Unless you know what the code for the extended stored procedure is and what it is doing, it is impossible to understand why this wait type is coming up. Reducing MSQL_XP wait: As discussed, it is hard to understand the Extended Stored Procedure if the code for it is not available. In the scenario described at the beginning of this post, our client was using third-party backup tool. The third-party backup tool was using Extended Stored Procedure. After we learned that this wait type was coming from the extended stored procedure of the backup tool they were using, we contacted the tech team of its vendor. The vendor admitted that the code was not optimal at some places, and within that day they had provided the patch. Once the updated version was installed, the issue on this wait type disappeared. As viewed in the wait statistics of all the 100+ SQL Server, there was no more MSSQL_XP wait type found. In simpler terms, you must first identify which Extended Stored Procedure is creating the wait type of MSSQL_XP and see if you can get in touch with the creator of the SP so you can help them optimize the code. If you have encountered this MSSQL_XP wait type, I encourage all of you to write how you managed it. Please do not mention the name of the vendor in your comment as I will not approve it. The focus of this blog post is to understand the wait types; not talk about others. Read all the post in the Wait Types and Queue series. Note: The information presented here is from my experience and there is no way that I claim it to be accurate. I suggest reading Book OnLine for further clarification. All the discussion of Wait Stats in this blog is generic and varies from system to system. It is recommended that you test this on a development server before implementing it to a production server. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Wait Stats, SQL Wait Types, T SQL, Technology

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  • Instant Rename and Rename Refactoring

    - by Petr
    During the last weeks I have got  a few questions about rename refactoring and some users also complain to me that the refactoring in NetBeans 6.x was much faster. So I would like to explain the situation. For some people, who don't know, Instant Rename action and Rename Refactoring  can look like one action. But it's not true, even if  both actions use the same shortcut (CTRL + R). NetBeans 6.x contained only Instant Rename action (speaking about PHP support), which we can mark as very simple rename refactoring through one file. From NetBeans 7.0 the Instant Rename action works only in "non public" context. It means that this action is used for fast renaming variables that has local context like inside a method, or for renaming private methods and fields that can not be used outside of the scope, where they are declared. From user point of view these two action can be simply recognized. When is after CTRL+R called Instant Rename action, then the identifier is surrounded with rectangle and you can rename it directly in the file. It's fast and simple, also the usages of this identifier are renamed in the same time as you write. The picture below shows Instant Rename action for $message identifier, that is visible only in the print_test method and due this after CTRL+R is called Instant Rename. In NetBeans 7.0, there was added Rename Refactoring that is called for public identifiers. It means for identifiers that could be used in other files. If you press CTRL+R shortcut when the caret is inside $hello identifier from the picture above, NetBeans recognizes that $hello is declared / used in a global context and calls the Rename Refactoring that brings a dialog to change the name of the identifier. From this dialog you have to preview suggested changes, through pressing Preview button and then execute the refactoring through Do Refactoring button. Yes, it's more complicated from user point of view than Instant Rename, but in Rename Refactoring NetBeans can change more files at once. It should be  the developer responsibility to decide whether the suggested changes are right and the refactoring can be executed or in some files original name should be kept. Someone can argue that he doesn't use $hello variable in any other file so Instant Rename could be used in such case. Yes it's true, but in such case NetBeans has to know all usages of all identifiers and keep this informations up to date during editing a file. I'm sure that this is not possible due to the performance problems, mainly for big projects. So the usages are computed after pressing the Preview button. And why is the Refactor button always disabled in the Rename dialog and user has to always go through the preview phase? NetBeans has API and SPI for implementing refactoring actions and this dialog is a part of this infrastructure. If you rename an identifier for example in Java, the Refactor buttons is enabled, but Java is strongly type language and you can be almost in 99% sure that the IDE will suggest the right results. In PHP as a dynamic language, we can not be sure, what NetBeans finds is only a "guess". This is why NetBeans pushes developers to preview the changes for PHP rename. I hope that I have explain it clearly. I'm open to any discussion. What I have described above is situation in NetBeans 7.0, 7.0.1 and probably it will be also in NetBeans 7.1, because there is no plan to change it. Please write your opinion here.

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  • Watch Netflix Instant Movies in Boxee

    - by DigitalGeekery
    Boxee is multi-platform Media PC application with a host of media applications. One of which is the popular Movie service, Netflix. Today we’ll show you how to get setup to watch Netflix Instant streaming video in Boxee. Note: Nexflix requires Microsoft Silverlight which unfortunately means Boxee users running Linux out of luck. What You’ll Need A Netflix account Authorize your Netflix account with Boxee Install Microsoft Silverlight Authorize Your Netflix Account First, we need to authorize our Netflix account with Boxee. (See link below). Type in your Boxee username and password and click “Login.”  When prompted, click “Authorize.”   Click “Yes, Link This Account.”    Install Silverlight If you don’t already have Silverlight installed, you’ll need to do so. See the download link at the end of the article.   Log into Boxee Now we’re ready to log into Boxee. Once logged in, click on “Apps” on the Home screen.   From the My Apps screen click on Netflix. Then click “Start.” Click “Yes” to enable the cookie.   Now you’ll enter the Netflix App. From here, you can browse your Instant Queue, Recommendations, New Arrivals, Browse Genre, or Search for available titles.   Click on a selection you’d like to watch. From here, you can Play, Rate, or even add the title to your regular Netflix Queue.   With a remote or the on-screen controls you can pause, stop, play, and skip forward or back through the video.   Now you’re all set to enjoy the Netflix Instant library with Boxee. Netflix Instant is one of many great Apps included with Boxee. While the current available selection isn’t exactly overwhelming, most subscribers will likely find enough to keep themselves entertained in between DVD deliveries. Haven’t tried Boxee yet? Check out our article on getting started with Boxee. Links Authorize your Netflix account with Boxee Install Microsoft Silverlight Similar Articles Productive Geek Tips Using Netflix Watchnow in Windows Vista Media Center (Gmedia)Find Movies and TV Based on your Mood with JinniGetting Started with BoxeeQuickly Find Movies to Watch at Hello MoviesIntegrate Boxee with Media Center in Windows 7 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Change DNS servers on the fly with DNS Jumper Live PDF Searches PDF Files and Ebooks Converting Mp4 to Mp3 Easily Use Quick Translator to Translate Text in 50 Languages (Firefox) Get Better Windows Search With UltraSearch Scan News With NY Times Article Skimmer

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  • SQL SERVER – How to Compare the Schema of Two Databases with Schema Compare

    - by Pinal Dave
    Earlier I wrote about An Efficiency Tool to Compare and Synchronize SQL Server Databases and it was very much well received. Since the blog post I have received quite a many question that just like data how we can also compare schema and synchronize it. If you think about comparing the schema manually, it is almost impossible to do so. Table Schema has been just one of the concept but if you really want the all the schema of the database (triggers, views, stored procedure and everything else) it is just impossible task. If you are developer or database administrator who works in the production environment than you know that there are so many different occasions when we have to compare schema of the database. Before deploying any changes to the production server, I personally like to make note of the every single schema change and document it so in case of any issue , I can always go back and refer my documentation. As discussed earlier it is absolutely impossible to do this task without the help of third party tools. I personally use Devart Schema Compare for this task. This is an extremely easy tool. Let us see how it works. First I have two different databases – a) AdventureWorks2012 and b) AdventureWorks2012-V1. There are total three changes between these databases. Here is the list of the same. One of the table has additional column One of the table have new index One of the stored procedure is changed Now let see how dbForge Schema Compare works in this scenario. First open dbForge Schema Compare studio. Click on New Schema Comparison. It will bring you to following screen where we have to configure the database needed to configure. I have selected AdventureWorks2012 and AdventureWorks-V1 databases. In the next screen we can verify various options but for this demonstration we will keep it as it is. We will not change anything in schema mapping screen as in our case it is not required but generically if you are comparing across schema you may need this. This is the most important screen as on this screen we select which kind of object we want to compare. You can see the options which are available to select. The screen lets you select the objects from SQL Server 2000 to SQL Server 2012. Once you click on compare in previous screen it will bring you to this screen, which will essentially display the comparative difference between two of the databases which we had selected in earlier screen. As mentioned above there are three different changes in the database and the same has been listed over here. Two of the changes belongs to the tables and one changes belong to the procedure. Let us click each of them one by one to see what is the difference between them. In very first option we can see that there is an additional column in another database which did not exist earlier. In this example we can see that AdventureWorks2012 database have an additional index. Following example is very interesting as in this case, we have changed the definition of the stored procedure and the result pan contains the same. dbForget Schema Compare very effectively identify the changes in schema and lists them neatly to developers. Here is one more screen. This software not only compares the schema but also provides the options to update or drop them as per the choice. I think this is brilliant option. Well, I have been using schema compare for quite a while and have found it very useful. Here are few of the things which dbForge Schema Compare can do for developers and DBAs. Compare and synchronize SQL Server database schemas Compare schemas of live database and SQL Server backup Generate comparison reports in Excel and HTML formats Eliminate mistakes in schema changes propagation across environments Track production database changes and customizations Automate migration of schema changes using command line interface I suggest that you try out dbForge Schema Compare and let me know what you think of this product. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Utility, T SQL

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  • HTML5 Form Validation

    - by Stephen.Walther
    The latest versions of Google Chrome (16+), Mozilla Firefox (8+), and Internet Explorer (10+) all support HTML5 client-side validation. It is time to take HTML5 validation seriously. The purpose of the blog post is to describe how you can take advantage of HTML5 client-side validation regardless of the type of application that you are building. You learn how to use the HTML5 validation attributes, how to perform custom validation using the JavaScript validation constraint API, and how to simulate HTML5 validation on older browsers by taking advantage of a jQuery plugin. Finally, we discuss the security issues related to using client-side validation. Using Client-Side Validation Attributes The HTML5 specification discusses several attributes which you can use with INPUT elements to perform client-side validation including the required, pattern, min, max, step, and maxlength attributes. For example, you use the required attribute to require a user to enter a value for an INPUT element. The following form demonstrates how you can make the firstName and lastName form fields required: <!DOCTYPE html> <html > <head> <title>Required Demo</title> </head> <body> <form> <label> First Name: <input required title="First Name is Required!" /> </label> <label> Last Name: <input required title="Last Name is Required!" /> </label> <button>Register</button> </form> </body> </html> If you attempt to submit this form without entering a value for firstName or lastName then you get the validation error message: Notice that the value of the title attribute is used to display the validation error message “First Name is Required!”. The title attribute does not work this way with the current version of Firefox. If you want to display a custom validation error message with Firefox then you need to include an x-moz-errormessage attribute like this: <input required title="First Name is Required!" x-moz-errormessage="First Name is Required!" /> The pattern attribute enables you to validate the value of an INPUT element against a regular expression. For example, the following form includes a social security number field which includes a pattern attribute: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Pattern</title> </head> <body> <form> <label> Social Security Number: <input required pattern="^\d{3}-\d{2}-\d{4}$" title="###-##-####" /> </label> <button>Register</button> </form> </body> </html> The regular expression in the form above requires the social security number to match the pattern ###-##-####: Notice that the input field includes both a pattern and a required validation attribute. If you don’t enter a value then the regular expression is never triggered. You need to include the required attribute to force a user to enter a value and cause the value to be validated against the regular expression. Custom Validation You can take advantage of the HTML5 constraint validation API to perform custom validation. You can perform any custom validation that you need. The only requirement is that you write a JavaScript function. For example, when booking a hotel room, you might want to validate that the Arrival Date is in the future instead of the past: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Constraint Validation API</title> </head> <body> <form> <label> Arrival Date: <input id="arrivalDate" type="date" required /> </label> <button>Submit Reservation</button> </form> <script type="text/javascript"> var arrivalDate = document.getElementById("arrivalDate"); arrivalDate.addEventListener("input", function() { var value = new Date(arrivalDate.value); if (value < new Date()) { arrivalDate.setCustomValidity("Arrival date must be after now!"); } else { arrivalDate.setCustomValidity(""); } }); </script> </body> </html> The form above contains an input field named arrivalDate. Entering a value into the arrivalDate field triggers the input event. The JavaScript code adds an event listener for the input event and checks whether the date entered is greater than the current date. If validation fails then the validation error message “Arrival date must be after now!” is assigned to the arrivalDate input field by calling the setCustomValidity() method of the validation constraint API. Otherwise, the validation error message is cleared by calling setCustomValidity() with an empty string. HTML5 Validation and Older Browsers But what about older browsers? For example, what about Apple Safari and versions of Microsoft Internet Explorer older than Internet Explorer 10? What the world really needs is a jQuery plugin which provides backwards compatibility for the HTML5 validation attributes. If a browser supports the HTML5 validation attributes then the plugin would do nothing. Otherwise, the plugin would add support for the attributes. Unfortunately, as far as I know, this plugin does not exist. I have not been able to find any plugin which supports both the required and pattern attributes for older browsers, but does not get in the way of these attributes in the case of newer browsers. There are several jQuery plugins which provide partial support for the HTML5 validation attributes including: · jQuery Validation — http://docs.jquery.com/Plugins/Validation · html5Form — http://www.matiasmancini.com.ar/jquery-plugin-ajax-form-validation-html5.html · h5Validate — http://ericleads.com/h5validate/ The jQuery Validation plugin – the most popular JavaScript validation library – supports the HTML5 required attribute, but it does not support the HTML5 pattern attribute. Likewise, the html5Form plugin does not support the pattern attribute. The h5Validate plugin provides the best support for the HTML5 validation attributes. The following page illustrates how this plugin supports both the required and pattern attributes: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>h5Validate</title> <style type="text/css"> .validationError { border: solid 2px red; } .validationValid { border: solid 2px green; } </style> </head> <body> <form id="customerForm"> <label> First Name: <input id="firstName" required /> </label> <label> Social Security Number: <input id="ssn" required pattern="^\d{3}-\d{2}-\d{4}$" title="Expected pattern is ###-##-####" /> </label> <input type="submit" /> </form> <script type="text/javascript" src="Scripts/jquery-1.4.4.min.js"></script> <script type="text/javascript" src="Scripts/jquery.h5validate.js"></script> <script type="text/javascript"> // Enable h5Validate plugin $("#customerForm").h5Validate({ errorClass: "validationError", validClass: "validationValid" }); // Prevent form submission when errors $("#customerForm").submit(function (evt) { if ($("#customerForm").h5Validate("allValid") === false) { evt.preventDefault(); } }); </script> </body> </html> When an input field fails validation, the validationError CSS class is applied to the field and the field appears with a red border. When an input field passes validation, the validationValid CSS class is applied to the field and the field appears with a green border. From the perspective of HTML5 validation, the h5Validate plugin is the best of the plugins. It adds support for the required and pattern attributes to browsers which do not natively support these attributes such as IE9. However, this plugin does not include everything in my wish list for a perfect HTML5 validation plugin. Here’s my wish list for the perfect back compat HTML5 validation plugin: 1. The plugin would disable itself when used with a browser which natively supports HTML5 validation attributes. The plugin should not be too greedy – it should not handle validation when a browser could do the work itself. 2. The plugin should simulate the same user interface for displaying validation error messages as the user interface displayed by browsers which natively support HTML5 validation. Chrome, Firefox, and Internet Explorer all display validation errors in a popup. The perfect plugin would also display a popup. 3. Finally, the plugin would add support for the setCustomValidity() method and the other methods of the HTML5 validation constraint API. That way, you could implement custom validation in a standards compatible way and you would know that it worked across all browsers both old and new. Security It would be irresponsible of me to end this blog post without mentioning the issue of security. It is important to remember that any client-side validation — including HTML5 validation — can be bypassed. You should use client-side validation with the intention to create a better user experience. Client validation is great for providing a user with immediate feedback when the user is in the process of completing a form. However, client-side validation cannot prevent an evil hacker from submitting unexpected form data to your web server. You should always enforce your validation rules on the server. The only way to ensure that a required field has a value is to verify that the required field has a value on the server. The HTML5 required attribute does not guarantee anything. Summary The goal of this blog post was to describe the support for validation contained in the HTML5 standard. You learned how to use both the required and the pattern attributes in an HTML5 form. We also discussed how you can implement custom validation by taking advantage of the setCustomValidity() method. Finally, I discussed the available jQuery plugins for adding support for the HTM5 validation attributes to older browsers. Unfortunately, I am unaware of any jQuery plugin which provides a perfect solution to the problem of backwards compatibility.

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  • Building a Mafia&hellip;TechFest Style

    - by David Hoerster
    It’s been a few months since I last blogged (not that I blog much to begin with), but things have been busy.  We all have a lot going on in our lives, but I’ve had one item that has taken up a surprising amount of time – Pittsburgh TechFest 2012.  After the event, I went through some minutes of the first meetings for TechFest, and I started to think about how it all came together.  I think what inspired me the most about TechFest was how people from various technical communities were able to come together and build and promote a common event.  As a result, I wanted to blog about this to show that people from different communities can work together to build something that benefits all communities.  (Hopefully I've got all my facts straight.)  TechFest started as an idea Eric Kepes and myself had when we were planning our next Pittsburgh Code Camp, probably in the summer of 2011.  Our Spring 2011 Code Camp was a little different because we had a great infusion of some folks from the Pittsburgh Agile group (especially with a few speakers from LeanDog).  The line-up was great, but we felt our audience wasn’t as broad as it should have been.  We thought it would be great to somehow attract other user groups around town and have a big, polyglot conference. We started contacting leaders from Pittsburgh’s various user groups.  Eric and I split up the ones that we knew about, and we just started making contacts.  Most of the people we started contacting never heard of us, nor we them.  But we all had one thing in common – we ran user groups who’s primary goal is educating our members to make them better at what they do. Amazingly, and I say this because I wasn’t sure what to expect, we started getting some interest from the various leaders.  One leader, Greg Akins, is, in my opinion, Pittsburgh’s poster boy for the polyglot programmer.  He’s helped us in the past with .NET Code Camps, is a Java developer (and leader in Pittsburgh’s Java User Group), works with Ruby and I’m sure a handful of other languages.  He helped make some e-introductions to other user group leaders, and the whole thing just started to snowball. Once we realized we had enough interest with the user group leaders, we decided to not have a Fall Code Camp and instead focus on this new entity. Flash-forward to October of 2011.  I set up a meeting, with the help of Jeremy Jarrell (Pittsburgh Agile leader) to hold a meeting with the leaders of many of Pittsburgh technical user groups.  We had representatives from 12 technical user groups (Python, JavaScript, Clojure, Ruby, PittAgile, jQuery, PHP, Perl, SQL, .NET, Java and PowerShell) – 14 people.  We likened it to a scene from a Godfather movie where the heads of all the families come together to make some deal.  As a result, the name “TechFest Mafia” was born and kind of stuck. Over the next 7 months or so, we had our starts and stops.  There were moments where I thought this event would not happen either because we wouldn’t have the right mix of topics (was I off there!), or enough people register (OK, I was wrong there, too!) or find an appropriate venue (hmm…wrong there, too) or find enough sponsors to help support the event (wow…not doing so well).  Overall, everything fell into place with a lot of hard work from Eric, Jen, Greg, Jeremy, Sean, Nicholas, Gina and probably a few others that I’m forgetting.  We also had a bit of luck, too.  But in the end, the passion that we had to put together an event that was really about making ourselves better at what we do really paid off. I’ve never been more excited about a project coming together than I have been with Pittsburgh TechFest 2012.  From the moment the first person arrived at the event to the final minutes of my closing remarks (where I almost lost my voice – I ended up being diagnosed with bronchitis the next day!), it was an awesome event.  I’m glad to have been part of bringing something like this to Pittsburgh…and I’m looking forward to Pittsburgh TechFest 2013.  See you there!

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  • Kanban Tools Review

    - by GeekAgilistMercenary
    The first two sessions on Sunday were Collaboration and why it is so hard and the following, which was a perfect following session was on Kanban.  While in that second session two online Saas Style Tools were mentioned; AgileZen and Leankit.  I decided right then and there that I would throw together some first impressions and setup some sample projects.  I did this by setting up an account and creating the projects. Agile Zen Account Creation Setting up the initial account required an e-mail verification, which is understandable.  Within a few seconds it was mailed out and I was logged in. Setting Up the Kanban Board The initial setup of the board was pretty easy.  I maybe clicked around an extra few times, but overall everything I needed to use the tool was immediately available.  The representation of everything was very similar to what one expects in a real Kanban Board too.  This is a HUGE plus, especially if a team is smart and places this tool in a centrally viewable area to allow for visibility. Each of the board items is just like a post it, being blue, grey, green, pink, or one of another few colors.  Dragging them onto each swim lane on the board was flawless, making changes through the work super easy and intuitive. The other thing I really liked about AgileZen is that the Kanban Board had the swim lanes setup immediately.  One can change them, but when you know you immediately need a Ready Lane, Working Lane, and a Complete Lane it is nice to just have them right in front of you in the interface.  In addition, the Backlog is simply a little tab on the left hand side.  This is perfect for the Backlog Queue.  Out of the way, with the focus on the primary items. Once  I got the items onto the board I was easily able to get back to the actual work at hand versus playing around with the tool.  The fact that it was so easy to use, fast and easy UX, and overall a great layout put me back to work on things I needed to do versus sitting a playing with the tool.  That, in the end is the key to using these tools. LeanKit Kanban Account Creation Setting up the account got me straight into the online tool.  This I thought was pretty cool. Setting Up the Kanban Board Setting up the Kanban Board within Leankit was a bit of trouble.  There were multiple UX issues in regard to process and intuitiveness.  The Leankit basically forces one to design the whole board first, making no assumptions about how the board should look.  The swim lanes in my humble opinion should be setup immediately without any manipulation with the most common lanes;  ready, working, and complete. The other UX hiccup that I had a problem with is that as soon as I managed to get the swim lanes into place, I wanted to remove the redundant Backlog Lane.  The Backlog Lane, or Backlog Bucket should be somewhere that I accidentally added as a lane.  Then on top of that I screwed up and added an item inside the lane, which then prevented me from deleting the lane.  I had to go back out of the lane manipulation, remove the item, and then remove the excess lane.  Summary Leankit wasn't a bad interface, it just wasn't as good as AgileZen.  The AgileZen interface was just better UX design overall.  AgileZen also presents a much better user interface graphical design all together.  It is much closer to what the Kanban Board would look like if it were a physical Kanban Board.  Since one of the HUGE reasons for Kanban is to increase visibility, the fact the design is similar to what a real Kanban Board is actually a pretty big deal. This is an image (click for larger) that shows the two Kanban Boards side by side.  The one on the left is AgileZen and the right is Leankit. Original Entry

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  • C#/.NET Little Wonders: The EventHandler and EventHandler&lt;TEventArgs&gt; delegates

    - by James Michael Hare
    Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. In the last two weeks, we examined the Action family of delegates (and delegates in general), and the Func family of delegates and how they can be used to support generic, reusable algorithms and classes. So this week, we are going to look at a handy pair of delegates that can be used to eliminate the need for defining custom delegates when creating events: the EventHandler and EventHandler<TEventArgs> delegates. Events and delegates Before we begin, let’s quickly consider events in .NET.  According to the MSDN: An event in C# is a way for a class to provide notifications to clients of that class when some interesting thing happens to an object. So, basically, you can create an event in a type so that users of that type can subscribe to notifications of things of interest.  How is this different than some of the delegate programming that we talked about in the last two weeks?  Well, you can think of an event as a special access modifier on a delegate.  Some differences between the two are: Events are a special access case of delegates They behave much like delegates instances inside the type they are declared in, but outside of that type they can only be (un)subscribed to. Events can specify add/remove behavior explicitly If you want to do additional work when someone subscribes or unsubscribes to an event, you can specify the add and remove actions explicitly. Events have access modifiers, but these only specify the access level of those who can (un)subscribe A public event, for example, means anyone can (un)subscribe, but it does not mean that anyone can raise (invoke) the event directly.  Events can only be raised by the type that contains them In contrast, if a delegate is visible, it can be invoked outside of the object (not even in a sub-class!). Events tend to be for notifications only, and should be treated as optional Semantically speaking, events typically don’t perform work on the the class directly, but tend to just notify subscribers when something of note occurs. My basic rule-of-thumb is that if you are just wanting to notify any listeners (who may or may not care) that something has happened, use an event.  However, if you want the caller to provide some function to perform to direct the class about how it should perform work, make it a delegate. Declaring events using custom delegates To declare an event in a type, we simply use the event keyword and specify its delegate type.  For example, let’s say you wanted to create a new TimeOfDayTimer that triggers at a given time of the day (as opposed to on an interval).  We could write something like this: 1: public delegate void TimeOfDayHandler(object source, ElapsedEventArgs e); 2:  3: // A timer that will fire at time of day each day. 4: public class TimeOfDayTimer : IDisposable 5: { 6: // Event that is triggered at time of day. 7: public event TimeOfDayHandler Elapsed; 8:  9: // ... 10: } The first thing to note is that the event is a delegate type, which tells us what types of methods may subscribe to it.  The second thing to note is the signature of the event handler delegate, according to the MSDN: The standard signature of an event handler delegate defines a method that does not return a value, whose first parameter is of type Object and refers to the instance that raises the event, and whose second parameter is derived from type EventArgs and holds the event data. If the event does not generate event data, the second parameter is simply an instance of EventArgs. Otherwise, the second parameter is a custom type derived from EventArgs and supplies any fields or properties needed to hold the event data. So, in a nutshell, the event handler delegates should return void and take two parameters: An object reference to the object that raised the event. An EventArgs (or a subclass of EventArgs) reference to event specific information. Even if your event has no additional information to provide, you are still expected to provide an EventArgs instance.  In this case, feel free to pass the EventArgs.Empty singleton instead of creating new instances of EventArgs (to avoid generating unneeded memory garbage). The EventHandler delegate Because many events have no additional information to pass, and thus do not require custom EventArgs, the signature of the delegates for subscribing to these events is typically: 1: // always takes an object and an EventArgs reference 2: public delegate void EventHandler(object sender, EventArgs e) It would be insane to recreate this delegate for every class that had a basic event with no additional event data, so there already exists a delegate for you called EventHandler that has this very definition!  Feel free to use it to define any events which supply no additional event information: 1: public class Cache 2: { 3: // event that is raised whenever the cache performs a cleanup 4: public event EventHandler OnCleanup; 5:  6: // ... 7: } This will handle any event with the standard EventArgs (no additional information).  But what of events that do need to supply additional information?  Does that mean we’re out of luck for subclasses of EventArgs?  That’s where the generic for of EventHandler comes into play… The generic EventHandler<TEventArgs> delegate Starting with the introduction of generics in .NET 2.0, we have a generic delegate called EventHandler<TEventArgs>.  Its signature is as follows: 1: public delegate void EventHandler<TEventArgs>(object sender, TEventArgs e) 2: where TEventArgs : EventArgs This is similar to EventHandler except it has been made generic to support the more general case.  Thus, it will work for any delegate where the first argument is an object (the sender) and the second argument is a class derived from EventArgs (the event data). For example, let’s say we wanted to create a message receiver, and we wanted it to have a few events such as OnConnected that will tell us when a connection is established (probably with no additional information) and OnMessageReceived that will tell us when a new message arrives (probably with a string for the new message text). So for OnMessageReceived, our MessageReceivedEventArgs might look like this: 1: public sealed class MessageReceivedEventArgs : EventArgs 2: { 3: public string Message { get; set; } 4: } And since OnConnected needs no event argument type defined, our class might look something like this: 1: public class MessageReceiver 2: { 3: // event that is called when the receiver connects with sender 4: public event EventHandler OnConnected; 5:  6: // event that is called when a new message is received. 7: public event EventHandler<MessageReceivedEventArgs> OnMessageReceived; 8:  9: // ... 10: } Notice, nowhere did we have to define a delegate to fit our event definition, the EventHandler and generic EventHandler<TEventArgs> delegates fit almost anything we’d need to do with events. Sidebar: Thread-safety and raising an event When the time comes to raise an event, we should always check to make sure there are subscribers, and then only raise the event if anyone is subscribed.  This is important because if no one is subscribed to the event, then the instance will be null and we will get a NullReferenceException if we attempt to raise the event. 1: // This protects against NullReferenceException... or does it? 2: if (OnMessageReceived != null) 3: { 4: OnMessageReceived(this, new MessageReceivedEventArgs(aMessage)); 5: } The above code seems to handle the null reference if no one is subscribed, but there’s a problem if this is being used in multi-threaded environments.  For example, assume we have thread A which is about to raise the event, and it checks and clears the null check and is about to raise the event.  However, before it can do that thread B unsubscribes to the event, which sets the delegate to null.  Now, when thread A attempts to raise the event, this causes the NullReferenceException that we were hoping to avoid! To counter this, the simplest best-practice method is to copy the event (just a multicast delegate) to a temporary local variable just before we raise it.  Since we are inside the class where this event is being raised, we can copy it to a local variable like this, and it will protect us from multi-threading since multicast delegates are immutable and assignments are atomic: 1: // always make copy of the event multi-cast delegate before checking 2: // for null to avoid race-condition between the null-check and raising it. 3: var handler = OnMessageReceived; 4: 5: if (handler != null) 6: { 7: handler(this, new MessageReceivedEventArgs(aMessage)); 8: } The very slight trade-off is that it’s possible a class may get an event after it unsubscribes in a multi-threaded environment, but this is a small risk and classes should be prepared for this possibility anyway.  For a more detailed discussion on this, check out this excellent Eric Lippert blog post on Events and Races. Summary Generic delegates give us a lot of power to make generic algorithms and classes, and the EventHandler delegate family gives us the flexibility to create events easily, without needing to redefine delegates over and over.  Use them whenever you need to define events with or without specialized EventArgs.   Tweet Technorati Tags: .NET, C#, CSharp, Little Wonders, Generics, Delegates, EventHandler

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  • Make Your Mouse Pointers Left-hand Friendly

    - by Matthew Guay
    It’s a right-centric world, with everything from pencils to computer mice expecting you to be right-handed.  Here’s how you can train your mouse and cursors in Windows 7 and Vista to respect your left-handedness. Using your Left Hand the Right Way It’s easy to switch your mouse to left-handed mode.  Enter “mouse” in your Start menu search, and select the first entry. Check the “Switch primary and secondary buttons” box to make your mouse more left-hand friendly.  Now your primary select button is your right button, and the secondary button (commonly referred to as right-click) is the left button. But, it can still be awkward to select items on screen with your left hand using the default cursors.  MSDN has a free set of cursors designed for left-handed users, that can fix this problem for you.  These cursors are exactly like the default Aero cursors in Windows 7 and Vista, except they are reversed to make them better for left-handed use. The cursors are available in 3 sizes: normal, large, and extra large.  The normal ones are the same size as the default ones in Windows 7; feel free to choose the other sizes if you prefer them.  Click each link to download all 6 cursors for your size (link below). Click “I Agree” after selecting the cursors to accept the license agreement and download them. Once you have all 6 cursors downloaded, select the Pointers tab in the Mouse Properties dialog.  Click the cursor to change, and then click Browse to select the new cursor. Browse to the folder you downloaded your new cursors to, select the correct cursor, and click Open. Do this for each of the 6 cursors to be changed.  Strangely, the Busy cursor (the spinning blue orb) is a static cursor, so you may not wish to change it.  All the other ones look and act like their standard counterparts. Here’s the cursors to be changed, and their equivalents in the default cursors: Normal Select: aero_arrow_left.cur Help Select: aero_helpsel_left.cur Working in Background: aero_working_left.ani Busy: aero_busy_left.cur Handwriting: aero_pen_left.cur Link Select: aero_link_left.cur After changing all the cursors, click Save As… to save this mouse scheme so you can easily select it in the future.  Finally click Ok to close the Mouse Properties dialog and accept the changes. Now your pointers will be easier to use left-handed! Conclusion Whether you’re right-handed or left-handed, you can enjoy the Aero cursors in Windows 7 or Vista in the way that works best for you.  Unfortunately, many mice are still designed for right-handed people, but this trick will help you make the best out of your mouse. We included all of the 6 cursors for you in a zip file you can download Here. This will make it easier for you to get them all together without having to download them individually. Link Download Left-Handed Mouse Pointers from MSDN Similar Articles Productive Geek Tips Prevent Themes From Modifying Icons and Cursors in Windows 7How To Personalize Windows 7 StarterShow Two Time Zones in Your Outlook 2007 CalendarMake Mouse Navigation Faster in WindowsWhy Doesn’t Tab Work for Drop-down Controls in Firefox on OS X? TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Microsoft’s “How Do I ?” Videos Home Networks – How do they look like & the problems they cause Check Your IMAP Mail Offline In Thunderbird Follow Finder Finds You Twitter Users To Follow Combine MP3 Files Easily QuicklyCode Provides Cheatsheets & Other Programming Stuff

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  • Plymouth and GRUB do not show at all

    - by WarriorIng64
    I am using Ubuntu 11.04 64-bit as my only OS on my desktop computer, which used to only run Ubuntu 10.04 LTS until I had the time to upgrade it with a fresh install. It uses integrated NVIDIA graphics (listed as a GeForce 6150SE nForce 430 by the NVIDIA X Server Settings utility) with the current proprietary driver as provided by the Additional Drivers utility, and has a VGA connection to a 1680x1050 Acer monitor. I used to get the (ugly-looking version of) Plymouth graphical boot screen while under 10.04. It didn't look that great, but I was fine with it. Now, it doesn't show on 11.04 at all during boot (I just get an error message in a moving gray box from the monitor saying "Input Not Supported"), and only rarely it will show on shutdown, all garbled up. I could not get GRUB to show during boot while holding down Shift, either (same error message), but pressing Enter while it should be up starts the system normally. A picture of the error message I was getting: Once fully booted, the system still shows the login screen and desktop just fine. Any information on how to troubleshoot this would be appreciated. If there's any hardware-specific stuff I forgot to include here, let me know the relevant commands to run in a comment below. Things that I've tried: Running plymouth in a framebuffer: no effect Booting with nomodeset as my grub boot: option no effect Booting with nomodeset and plymouth in a framebuffer: no effect other than Plymouth showing during shutdown only Following the Softpedia instructions for fixing Plymouth's resolution: Problem mostly solved, except logo does not show in Plymouth during boot, and both grub and Plymouth are slightly off-center #4 above, but with nomodeset removed as a grub boot option: same effect as #4 #5 above, but with vt.handoff=7 added as a grub boot option: same effect as #4 I have added the current contents of /etc/default/grub as requested in the comments: # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 GRUB_HIDDEN_TIMEOUT=0 GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash video=uvesafb:mode_option=1280x1024-24,mtrr=3,scroll=ywrap" GRUB_CMDLINE_LINUX="" # Uncomment to enable BadRAM filtering, modify to suit your needs # This works with Linux (no patch required) and with any kernel that obtains # the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...) #GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef" # Uncomment to disable graphical terminal (grub-pc only) #GRUB_TERMINAL=console # The resolution used on graphical terminal # note that you can use only modes which your graphic card supports via VBE # you can see them in real GRUB with the command `vbeinfo' GRUB_GFXMODE=1280x1024 # Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux #GRUB_DISABLE_LINUX_UUID=true # Uncomment to disable generation of recovery mode menu entries #GRUB_DISABLE_RECOVERY="true" # Uncomment to get a beep at grub start #GRUB_INIT_TUNE="480 440 1" CURRENT STATUS: I forgot to uncomment one line as per "things that I've tried" #4, so I took care of that. I can now see GRUB during startup when I hold Shift and a normal-looking Plymouth during shutdown...but Plymouth during boot is now just a solid purple screen. In each case, it's displayed a little off-center to the left, with a thin black bar running down the right side of the monitor. The error pictured above no longer shows. I'd say this problem is about 2/3 solved now. UPDATE: After Natty started freezing up on me, I decided to dual-boot with Oneiric, which unfortunately shows the same problems. Rather than trying all these workarounds though, I decided to do what I should have done from the start and file a pair of bug reports. LAST UPDATE: Bug 850908 has been confirmed as a legitimate nouveaufb bug. I have overwritten my 11.04 partition with 12.04 LTS, and I can confirm at this time that the issue is present there, as well. I will now flag this question to be closed, yet I hope it was helpful for anyone who experienced similar issues; if you are still having the same problem as me, please go there and mark yourself as affected. Thanks!

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  • OSB and Coherence Integration

    - by mark.ms.smith
    Anyone who has tried to manage Coherence nodes or tried to cache results in OSB, will appreciate the new functionality now available. As of WebLogic Server 10.3.4, you can use the WebLogic Administration Server, via the Administration Console or WLST, and java-based Node Manager to manage and monitor the life cycle of stand-alone Coherence cache servers. This is a great step forward as the previous options mainly involved writing your own scripts to do this. You can find an excellent description of how this works at James Bayer’s blog. You can also find the WebLogic documentation here.As of Oracle Service Bus 11gR1 (11.1.1.3.0), OSB now supports service result caching for Business Bervices with Coherence. If you use Business Services that return somewhat static results that do not change often, you can configure those Business Services to cache results. For Business Services that use result caching, you can control the time to live for the cached result. After the cached result expires, the next Business Service call results in invoking the back-end service to get the result. This result is then stored in the cache for future requests to access. I’m thinking that this caching functionality would be perfect for some sort of cross reference data that was refreshed nightly by batch. You can find the OSB Business Service documentation here.Result Caching in a dedicated JVMThis example demonstrates these new features by configuring a OSB Business Service to cache results in a separate Coherence JVM managed by WebLogic. The reason why you may want to use a separate, dedicated JVM is that the result cache data could potentially be quite large and you may want to protect your OSB java heap.In this example, the client will call an OSB Proxy Service to get Employee data based on an Employee Id. Using a Business Service, OSB calls an external system. The results are automatically cached and when called again, the respective results are retrieved from the cache rather than the external system.Step 1 – Set up your Coherence Server Via the OSB Administration Server Console, create your Coherence Server to be used as the results cache.Here are the configured Coherence Server arguments from the Server Start tab. Note that I’m using the default Cache Config and Override files in the domain.-Xms256m -Xmx512m -XX:PermSize=128m -XX:MaxPermSize=256m -Dtangosol.coherence.override=/app/middleware/jdev_11.1.1.4/user_projects/domains/osb_domain2/config/osb/coherence/osb-coherence-override.xml -Dtangosol.coherence.cluster=OSB-cluster -Dtangosol.coherence.cacheconfig=/app/middleware/jdev_11.1.1.4/user_projects/domains/osb_domain2/config/osb/coherence/osb-coherence-cache-config.xml -Dtangosol.coherence.distributed.localstorage=true -Dtangosol.coherence.management=all -Dtangosol.coherence.management.remote=true -Dcom.sun.management.jmxremote Just incase you need it, here is my Coherence Server classpath:/app/middleware/jdev_11.1.1.4/oracle_common/modules/oracle.coherence_3.6/coherence.jar: /app/middleware/jdev_11.1.1.4/modules/features/weblogic.server.modules.coherence.server_10.3.4.0.jar: /app/middleware/jdev_11.1.1.4/oracle_osb/lib/osb-coherence-client.jarBy default, OSB will try and create a local result cache instance. You need to disable this by adding the following JVM parameters to each of the OSB Managed Servers:-Dtangosol.coherence.distributed.localstorage=false -DOSB.coherence.cluster=OSB-clusterIf you need more information on configuring a remote result cache, have a look at the configuration documentration under the heading Using an Out-of-Process Coherence Cache Server.Step 2 – Configure your Business Service Under the respective Business Service Message Handling Configuration (Advanced Properties), you need to enable “Result Caching”. Additionally, you need to determine what the cache data will be keyed on. In the example below, I’m keying it on the unique Employee Id.The Results As this test was on my laptop, the actual timings are just an indication that there is a benefit to caching results. Using my test harness, I sent 10,000 requests to OSB, all with the same Employee Id. In this case, I had result caching disabled.You can see that this caused the back end Business Service (BS_GetEmployeeData) to be called for each request. Then after enabling result caching, I sent the same number of identical requests.You can now see the Business Service was only invoked once on the first request. All subsequent requests used the Results Cache.

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  • Don&rsquo;t Kill the Password

    - by Anthony Trudeau
    A week ago Mr. Honan from Wired.com penned an article on security he titled “Kill the Password: Why a String of Characters Can’t Protect Us Anymore.” He asserts that the password is not effective and a new solution is needed. Unfortunately, Mr. Honan was a victim of hacking. As a result he has a victim’s vendetta. His conclusion is ill conceived even though there are smatterings of truth and good advice. The password is a security barrier much like a lock on your door. In of itself it’s not guaranteeing protection. You can have a good password akin to a steel reinforced door with the best lock money can buy, or you can have a poor password like “password” which is like a sliding lock like on a bathroom stall. But, just like in the real world a lock isn’t always enough. You can have a lock, security system, video cameras, guard dogs, and even armed security guards; but none of that guarantees your protection. Even top secret government agencies can be breached by someone who is just that good (as dramatized in movies like Mission Impossible). And that’s the crux of it. There are real hackers out there that are that good. Killer coding ninja monkeys do exist! We still have locks on our doors, because they still serve their role. Passwords are no different. Security doesn’t end with the password. Most people would agree that stuffing your mattress with your life savings isn’t a good idea even if you have the best locks and security system. Most people agree its safest to have the money in a bank. Essentially this is compartmentalization. Compartmentalization extends to the online world as well. You’re at risk if your online banking accounts are linked to the same account as your social networks. This is especially true if you’re lackadaisical about linking those social networks to outside sources including apps. The object here is to minimize the damage that can be done. An attacker should not be able to get into your bank account, because they breached your Twitter account. It’s time to prioritize once you’ve compartmentalized. This simply means deciding how much security you want for the different compartments which I’ll call security zones. Social networking applications like Facebook provide a lot of security features. However, security features are almost always a compromise with privacy and convenience. It’s similar to an engineering adage, but in this case it’s security, convenience, and privacy – pick two. For example, you might use a safe instead of bank to store your money, because the convenience of having your money closer or the privacy of not having the bank records is more important than the added security. The following are lists of security do’s and don’ts (these aren’t meant to be exhaustive and each could be an article in of themselves): Security Do’s: Use strong passwords based on a phrase Use encryption whenever you can (e.g. HTTPS in Facebook) Use a firewall (and learn to use it properly) Configure security on your router (including port blocking) Keep your operating system patched Make routine backups of important files Realize that if you’re not paying for it, you’re the product Security Don’ts Link accounts if at all possible Reuse passwords across your security zones Use real answers for security questions (e.g. mother’s maiden name) Trust anything you download Ignore message boxes shown by your system or browser Forget to test your backups Share your primary email indiscriminately Only you can decide your comfort level between convenience, privacy, and security. Attackers are going to find exploits in software. Software is complex and depends on other software. The exploits are the responsibility of the software company. But your security is always your responsibility. Complete security is an illusion. But, there is plenty you can do to minimize the risk online just like you do in the physical world. Be safe and enjoy what the Internet has to offer. I expect passwords to be necessary just as long as locks.

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