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  • Hibernate Relationship Mapping/Speed up batch inserts

    - by manyxcxi
    I have 5 MySQL InnoDB tables: Test,InputInvoice,InputLine,OutputInvoice,OutputLine and each is mapped and functioning in Hibernate. I have played with using StatelessSession/Session, and JDBC batch size. I have removed any generator classes to let MySQL handle the id generation- but it is still performing quite slow. Each of those tables is represented in a java class, and mapped in hibernate accordingly. Currently when it comes time to write the data out, I loop through the objects and do a session.save(Object) or session.insert(Object) if I'm using StatelessSession. I also do a flush and clear (when using Session) when my line count reaches the max jdbc batch size (50). Would it be faster if I had these in a 'parent' class that held the objects and did a session.save(master) instead of each one? If I had them in a master/container class, how would I map that in hibernate to reflect the relationship? The container class wouldn't actually be a table of it's own, but a relationship all based on two indexes run_id (int) and line (int). Another direction would be: How do I get Hibernate to do a multi-row insert?

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  • Work with function references

    - by Ockonal
    Hello, I have another one question about functions reference. For example, I have such definition: typedef boost::function<bool (Entity &handle)> behaviorRef; std::map< std::string, ptr_vector<behaviorRef> > eventAssociation; The first question is: how to insert values into such map object? I tried: eventAssociation.insert(std::pair< std::string, ptr_vector<behaviorRef> >(eventType, ptr_vector<behaviorRef>(callback))); But the error: no matching function for call to ‘boost::ptr_vector<boost::function<bool(Entity&)> >::push_back(Entity::behaviorRef&)’ And I undersatnd it, but can't make workable code. The second question is how to call such functions? For example, I have one object of behaviorRef, how to call it with boost::bind with passing my own values?

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  • Adding an keyUp-event to form objects

    - by reporter
    Hello folks, I've got the issue to add a browser event to some input fields. The challenge I have to face is, that one parameter of my target function is the 'event'-variable and the second one an object. For a better understanding here some codes:The HTML object: <div id="1_dateFieldAdvanced" class="xp set"> <div id="1_dateFieldAdvanced_label" class="label">Birthday</div> <div id="1_dateFieldAdvanced_value" class="value date"> <input class="day" name="dayOfBirth" value="66" maxlength="2" type="text"> <input class="month" name="monthOfBirth" value="67" maxlength="2" type="text"> <input class="year" name="yearOfBirth" value="" maxlength="4" type="text"> </div> </div> The source code of target method is like below: function advancedDateFields(currentFieldAsObject, nextField, currentValueLength, ev){} Unfortunatly the HTML and the Javascript code is generated automatically, so I'm unable to refactore the code. My question is, how can I pass the key word 'event' and the other parameters? My tries did always fail. :-(

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  • image list, listview,picturebox

    - by user548694
    I wanted to show my pics in picturebox. but also wanted to show a preview of pics. When user select a pic, it is shown in picbox but i have problem in resoulution. Here is my code private void openToolStripMenuItem_Click(object sender, EventArgs e) { ofd = new OpenFileDialog(); ofd.Title = "Open an Image File"; ofd.FileName = ""; ofd.Filter = "Image Files(*.jpg; *.jpeg; *.gif; *.bmp)|*.jpg; *.jpeg; *.gif; *.bmp"; if (ofd.ShowDialog() == DialogResult.OK) { DirectoryInfo dir = new DirectoryInfo(@"c:\pic"); foreach (FileInfo file in dir.GetFiles()) { this.imageList1.Images.Add(Image.FromFile(file.FullName)); } this.listView1.View = View.LargeIcon; this.imageList1.ImageSize = new Size(40, 40); this.listView1.LargeImageList = this.imageList1; for (int j=0; j < this.imageList1.Images.Count; j++) { ListViewItem item = new ListViewItem(); item.ImageIndex = j; listView1.Items.Add(item); ListViewItem item2 = new ListViewItem(); item2.SubItems.Add(j.ToString()); } private void listView1_SelectedIndexChanged(object sender, EventArgs e) { int i = this.listView1.FocusedItem.Index; this.PicBox1.Image = this.imageList1.Images[i]; } On click i see only image of resolution of (40,40) becuse i have set it this.imageList1.ImageSize = new Size(40, 40); and not orignal size. How can I have it. 2- I want to write also image names and index(image no) under each images. Its it possible. reagrsd,

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  • Is `super` local variable?

    - by Michael
    // A : Parent @implementation A -(id) init { // change self here then return it } @end A A *a = [[A alloc] init]; a. Just wondering, if self is a local variable or global? If it's local then what is the point of self = [super init] in init? I can successfully define some local variable and use like this, why would I need to assign it to self. -(id) init { id tmp = [super init]; if(tmp != nil) { //do stuff } return tmp; } b. If [super init] returns some other object instance and I have to overwrite self then I will not be able to access A's methods any more, since it will be completely new object? Am I right? c. super and self pointing to the same memory and the major difference between them is method lookup order. Am I right? sorry, don't have Mac to try, learning theory as for now...

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  • Question about singleton property

    - by Jack
    I'm reading the java tutorial for enums located here and have a question: http://java.sun.com/j2se/1.5.0/docs/guide/language/enums.html#Card The part i'm confused about is as follows: "The Card class, above, contains a static factory that returns a deck, but there is no way to get an individual card from its rank and suit. Merely exposing the constructor would destroy the singleton property (that only a single instance of each card is allowed to exist). Here is how to write a static factory that preserves the singleton property, using a nested EnumMap: " Now as I understand, changing the original private "Card" constructor to public would allow us to instantiate an unlimited number of copies of a "Card" object with a given suit+rank. The solution as proposed was to create an EnumMap which would store four Maps (one for each suit), which themselves contained 13 Card objects with the rank as their keys. And so now if you wanted to retrieve a specific Card object from the deck, you would just call the "valueOf" method. My question now is, what's the prevent you with calling the valueOf method as many times as you like? Wouldn't that lead to the same problem as making the original private constructor public? Thanks.

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  • Custom class deallocated as soon as the app starts.

    - by Tangrs
    Heya, I've added a class object to the nib file. All connections are made. But for some reason, the object is deallocated as soon as it's created. Here's the code: control.h: #import <Foundation/Foundation.h> @interface control : NSObject { IBOutlet UILabel *PlayerScore; } -(IBAction) addPoint: sender; -(void) dealloc; @end control.m: #import "control.h" @implementation control -(IBAction)addPoint: sender { NSLog(@"Ohhai. Didn't crash."); //Doesn't even make it to this stage. int i = [PlayerScore.text intValue]; PlayerScore.text=[NSString stringWithFormat: @"%d",++i]; } -(void) dealloc { NSLog(@"ZOMGWTF?"); [super dealloc]; } @end Here is the console log: [Session started at 2010-06-09 19:47:57 +1000.] 2010-06-09 19:47:58.771 App[91100:207] ZOMGWTF? And after I click the button which messages addPoint, of course, it crashes. 2010-06-09 19:47:59.703 App[91100:207] * -[control] performSelector:withObject:withObject:]: message sent to deallocated instance 0x3843d80 Does anyone have any ideas?

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  • How to enforce jsf to create new instance of bean instead of throwing NullPointerException?

    - by Roman
    I'm almost sure that I do something wrong and thus the question's title is a bit incorrect. I have a form with several fields for creating a new User-objects (fields like login, password, birthday etc). And I have 2 buttons - Cancel and Create. I didn't finish Create yet :) , but when I press Cancel I see NullPointerException. Here is simplified code: <f:view> <h:form> <h:panelGroup layout="block"> <h:inputText id="add_login" value="#{userSupport.user.login}"/> <h:inputSecret id="add_password" value="#{userSupport.user.password}"/> <h:inputText id="add_name" value="#{userSupport.user.name}"/> <h:inputText id="add_surname" value="#{userSupport.user.surname}"/> <h:commandButton value="Cancel" action="cancel"/> </h:panelGroup> </h:form> </f:view> UserSupport class has field user with getter and setter and some other methods. It's a Spring bean with Session scope. When I press cancel, I see NPE because jsf tries to save values from inputs in user-object, but user-object is null. What is the correct way of doing this?

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  • vb Syntax error in INSERT INTO statement

    - by user201806
    im new in vb, i was create a program to connection ms access but when i run the program it get syntax error in Insert into statement, OleDbExpection was unhandled here my code Public Class Form2 Dim cnn As New OleDb.OleDbConnection Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load txtdate.Value = DateTime.Now cnn = New OleDb.OleDbConnection cnn.ConnectionString = "Provider=Microsoft.Jet.Oledb.4.0; Data Source=C:\Users\John\Documents\db.mdb" End Sub Private Sub btnsave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnsave.Click If Not cnn.State = ConnectionState.Open Then cnn.Open() End If Dim cmd As New OleDb.OleDbCommand cmd.Connection = cnn cmd.CommandText = "INSERT INTO sr(names,add,tel,dates,prob,serv,model,snm,acc,sna,remark)" & _ "VALUES ('" & Me.txtname.Text & "','" & Me.txtadd.Text & "','" & Me.txttel.Text & "', '" & _ Me.txtdate.Text & "','" & Me.txtpro.Text & "','" & Me.txtser.Text & "','" & Me.txtmod.Text & "', '" & _ Me.txtsnm.Text & "','" & Me.txtacc.Text & "','" & Me.txtsna.Text & "','" & Me.txtrem.Text & "')" cmd.ExecuteNonQuery() cnn.Close() End Sub End Class it's there any wrong with my code?

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  • FileInput Help/Advice

    - by user559142
    I have a fileinput class. It has a string parameter in the constructor to load the filename supplied. However it just exits if the file doesn't exist. I would like it to output a message if the file doesn't exist - but not sure how.... Here is the class: public class FileInput extends Input { /** * Construct <code>FileInput</code> object given a file name. */ public FileInput(final String fileName) { try { scanner = new Scanner(new FileInputStream(fileName)); } catch (FileNotFoundException e) { System.err.println("File " + fileName + " could not be found."); System.exit(1); } } /** * Construct <code>FileInput</code> object given a file name. */ public FileInput(final FileInputStream fileStream) { super(fileStream); } } And its implementation: private void loadFamilyTree() { out.print("Enter file name: "); String fileName = in.nextLine(); FileInput input = new FileInput(fileName); family.load(input); input.close(); }

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  • How do disable Rails submit buttons alongside Prototype helpers & RJS?

    - by Jesse
    I'm trying to follow this post http://stackoverflow.com/questions/576240/how-can-i-unobtrusively-disable-submit-buttons-with-javascript-and-prototype but I can't get it to work. The form triggers an RJS function, so I need to keep the helpers' onclick events intact. The RJS returns/reloads the same forms along with two new texts. I'm really confused. Here is my rails code for the forms: .span-20#comparison / new comparison . . . / voting forms (also reloaded) .span-4.prepend-3.append-6 - form_remote_tag :action => url_for(:controller => :comparisons), :method => :post do = hidden_field_tag :poem1_id, poems[:a].id = hidden_field_tag :poem2_id, poems[:b].id = hidden_field_tag :response, 1 = submit_tag "Vote for me", :disabled => false, :disable_with => 'Vote for me', :class => "compare" .span-4.append-3.last - form_remote_tag :action => url_for(:controller => :comparisons), :method => :post do = hidden_field_tag :poem1_id, poems[:a].id = hidden_field_tag :poem2_id, poems[:b].id = hidden_field_tag :response, 2 = submit_tag "Vote for me", :disable_with => 'Vote for me', :class => "compare" .span-4.prepend-8.append-8.prepend-top.last - form_remote_tag :action => url_for(:controller => :comparisons), :method => :post do = hidden_field_tag :poem1_id, poems[:a].id = hidden_field_tag :poem2_id, poems[:b].id = hidden_field_tag :response, 'draw' = submit_tag "Declare Draw", :disable_with => 'Declare Draw', :class => "compare" RJS page.replace_html :comparison, :partial => 'poems', :object => @poems page.insert_html :top, :previous, :partial => 'comparison', :object => @comparison page << "Effect.ScrollTo($('top'));"

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  • Is CDS a valid analogy for pointers? [closed]

    - by Flinkman
    So.. bear with me. I just found an analogy to c++ pointers and CDS. This clip describes CDS(Credit Default Swaps). http://www.youtube.com/watch?v=KPNdYtrlgaU#t=120s "Here we know we have an instrument of a particular financial instrument that is demonstrably dangerous, it creates long chains of risk which are vulnerable to the failure of individual trader or market partipants, in that chain and these instruments in an affect permit the creation of vicious spirals. In which the CDS price interact with the bound price, the market price and you can have a downward spiral." What my ears are telling me: "Don't create dependences that will create long chains of crashing systems." Update: Trying to clarify with something that is closer to the readers. If I change the words: instrument = construct financial = language trader = object market partipants = c structs CDS price = uptime bound price = outcome market price = ROI(return on incestment) The quote become more understandable. Look: "Here we know we have construct of a particular language construct that is demonstrably dangerous, it creates long chains of risk which are vulnerable to the failure of individual object or structs in that chain and these system in an affect permit the creation of vicious spirals. In which the uptime interact with the outcome, the ROI and you can have a downward spiral."

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  • How costly performance-wise are these actions in iPhone objective-C?

    - by Alex Gosselin
    This is really a few questions in one, I'm wondering what the performance cost is for these things, as I haven't really been following a best practice of any sort for these. The answers may also be useful to other readers, if somebody knows these. (1) If I need the core data managed object context, is it bad to use #import "myAppDelegate.h" //farther down in the code: NSManagedObjectContext *context = [(myAppDelegate.h*)[[UIApplication sharedApplication] delegate] managedObjectContext]; as opposed to leaving the warning you get if you don't cast the delegate? (2) What is the cheapest way to hard-code a string? I have been using return @"myString"; on occasion in some functions where I need to pass it to a variety of places, is it better to do it this way: static NSString *str = @"myString"; return str; (3) How costly is it to subclass an object i wrote vs. making a new one, in general? (4) When I am using core data and navigating through a hierarchy of some sort, is it necessary to turn things back into faults somehow after I read some info from them? or is this done automatically? Thanks for any help.

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  • Custom collision

    - by bali182
    I was recently assigned to create a siple game using the Corona SDK. The main pillar of the game would be a simple event: the user should put a ball in a basket, and I should be able to handle this event. Here is a picture for better understanding: I successfully managed to create the collision shape for the basket, but i have trouble with the collision of the inside of this basket. My first thought was the following: create a new shape size and position it to fit the "belly" of this basket add it to the physics-world, and listen to the collision. With hybrid drawing it looks like this: But there is a problem: if i add this shape to the physics, it wouldn't let the ball fall into the, basket, it will handle this shape as a solid object as well. So my question is: How could I get this custom object to collide, without blocking the ball to fall through it? I have read a lots of forum post with similar questions but none of them got a proper answer. There must be a way to do this in an elegant way. And one note: Please don't suggest checking the collision manually, with rectangle intersection, because in this simple case it would work, but later I may need to change the shape of the basket, and then it will be useless!

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  • customized form_for tag in rails

    - by poseid
    I want to make a table within a form by making a new form_tag. The following code in ApplicationHelper fails: module ApplicationHelper class TabularFormBuilder < ActionView::Helpers::FormBuilder # ... code to insert <tr> tags </tr> end def tabular_form_for(name, object = nil, options = nil, &proc) concat("<table>", proc.binding) form_for(name, object, (options||{}).merge(:builder => TabularFormBuilder), &proc) concat("</table>", proc.binding) end end The view I use is: <h1>New project</h1> <% tabular_form_for :project, :builder => ApplicationHelper::TabularFormBuilder do |f| %> <%= f.error_messages %> <%= f.text_field :name %> <%= f.text_area :description %> <%= f.text_field :location %> <%= f.submit 'Create' %> <% end %> The error I get is: NoMethodError in Projects#new Showing app/views/projects/new.html.erb where line #5 raised: undefined method `errors' for {:builder=ApplicationHelper::TabularFormBuilder}:Hash Any ideas how to make this custom tag work?

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  • Retrieving values from a table in HTML using jQuery?

    - by Mo
    Hi i was just wondering whats the best way to retrieve the following labels and values from this HTMl code using jquery and storing them in to a array or hash map of some sort where i have for e.g "DataSet:" : "prod" or ["Dataset", "Prod"]? <table id="metric_summary"> <tbody> <tr class="editable_metrics"> <td><label>DataSet:</label></td> <td><input name="DataSet" value="prod"></td> </tr> <tr class="editable_metrics"> <td><label>HostGroup:</label></td> <td><input name="HostGroup" value="MONITOR-PORTAL-IAD"></td> </tr> <tr class="editable_metrics"> <td><label>Host:</label></td> <td><input name="Host" value="ALL"></td> </tr> <tr class="editable_metrics"> <td><label>Class:</label></td> <td><input name="Class" value="CPU"></td> </tr> <tr class="editable_metrics"> <td><label>Object:</label></td> <td><input name="Object" value="cpu"></td> </tr> <tr class="editable_metrics"> <td><label>Metric:</label></td> <td><input name="Metric" value="CapacityCPUUtilization"></td> </tr> thanks

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  • ( Sql Server 2005 C#.Net ) - I want just the insert query for a temp table.

    - by John Stephen
    Hi..I am using C#.Net and Sql Server ( Windows Application ). I had created a temporary table. When a button is clicked, temporary table (#tmp_emp_details) is created. I am having another button called "insert Values" and also 5 textboxes. The values that are entered in the textbox are used and whenever com.ExecuteNonQuery(); line comes, it throws an error message called "Invalid object name '#tbl_emp_answer'.". Below is the set of code..Please give me a solution. Code for insert (in insert value button): private void btninsertvalues_Click(object sender, EventArgs e) { username = txtusername.Text; examloginid = txtexamloginid.Text; question = txtquestion.Text; answer = txtanswer.Text; useranswer = txtanswer.Text; SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=tempdb;Integrated Security=True;"); SqlCommand com = new SqlCommand("Insert into #tbl_emp_answer values('"+username+"','"+examloginid+"','"+question+"','"+answer+"','"+useranswer+"')", con); con.Open(); com.ExecuteNonQuery(); con.Close(); }

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  • help with basic MVC project

    - by Shrewd Demon
    hi, i am creating a demo MVC project and i am getting a Null Object Reference error for the following code. <% foreach (var item in Model) { %> <tr> <td> <%= Html.ActionLink("Edit", "Edit", new { /* id=item.PrimaryKey */ }) %> | <%= Html.ActionLink("Details", "Details", new { /* id=item.PrimaryKey */ })%> | <%= Html.ActionLink("Delete", "Delete", new { /* id=item.PrimaryKey */ })%> </td> <td> <%= Html.Encode(item.ContactEmail) %> </td> <td> <%= Html.Encode(item.YourQuery) %> </td> </tr> <% } %> i get an error in the first line itself (var item in Model) coz i am getting the Model object as null. Can anyone please help me. thanks.

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  • Get textboxes in to a list! c#

    - by Chelsea_cole
    public class Account { public string Username { get { return Username; } set { Username = value; } } } public class ListAcc { static void Data() { List<Account> UserList = new List<Account>(); //example of adding user account Account acc = new Account(); acc.Username = textBox1.Text; //error UserList.Add(acc); } } there are a error from access to textBox1.Text? ( An object reference is required for the nonstatic field, method, or property)... Someone can help? but if the code is: private void textBox1_TextChanged(object sender, EventArgs e) { List<Account> UserList = new List<Account>(); //example of adding user account Account acc = new Account(); acc.Username = textBox1.Text; UserList.Add(acc); } it's work! someone can help me fix my error? Many thanks!

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  • How to disable Rails submit buttons alongside Prototype helpers & RJS?

    - by Jesse
    I'm trying to follow this post http://stackoverflow.com/questions/576240/how-can-i-unobtrusively-disable-submit-buttons-with-javascript-and-prototype but I can't get it to work. The form triggers an RJS function, so I need to keep the helpers' onclick events intact. The RJS returns/reloads the same forms along with two new texts. I'm really confused. Here is my rails code for the forms: .span-20#comparison / new comparison . . . / voting forms (also reloaded) .span-4.prepend-3.append-6 - form_remote_tag :action => url_for(:controller => :comparisons), :method => :post do = hidden_field_tag :poem1_id, poems[:a].id = hidden_field_tag :poem2_id, poems[:b].id = hidden_field_tag :response, 1 = submit_tag "Vote for me", :disabled => false, :disable_with => 'Vote for me', :class => "compare" .span-4.append-3.last - form_remote_tag :action => url_for(:controller => :comparisons), :method => :post do = hidden_field_tag :poem1_id, poems[:a].id = hidden_field_tag :poem2_id, poems[:b].id = hidden_field_tag :response, 2 = submit_tag "Vote for me", :disable_with => 'Vote for me', :class => "compare" .span-4.prepend-8.append-8.prepend-top.last - form_remote_tag :action => url_for(:controller => :comparisons), :method => :post do = hidden_field_tag :poem1_id, poems[:a].id = hidden_field_tag :poem2_id, poems[:b].id = hidden_field_tag :response, 'draw' = submit_tag "Declare Draw", :disable_with => 'Declare Draw', :class => "compare" RJS page.replace_html :comparison, :partial => 'poems', :object => @poems page.insert_html :top, :previous, :partial => 'comparison', :object => @comparison page << "Effect.ScrollTo($('top'));"

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  • Is it okay to violate the principle that collection properties should be readonly for performance?

    - by uriDium
    I used FxCop to analyze some code I had written. I had exposed a collection via a setter. I understand why this is not good. Changing the backing store when I don't expect it is a very bad idea. Here is my problem though. I retrieve a list of business objects from a Data Access Object. I then need to add that collection to another business class and I was doing it with the setter method. The reason I did this was that it is going to be faster to make an assignment than to insert hundreds of thousands of objects one at a time to the collection again via another addElement method. Is it okay to have a getter for a collection in some scenarios? I though of rather having a constructor which takes a collection? I thought maybe I could pass the object in to the Dao and let the Dao populate it directly? Are there any other better ideas?

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  • How do I make this Java code operate properly? [Multi-threaded, race condition]

    - by Fixee
    I got this code from a student, and it does not work properly because of a race condition involving x++ and x--. He added synchronized to the run() method trying to get rid of this bug, but obviously this only excludes threads from entering run() on the same object (which was never a problem in the first place) but doesn't prevent independent objects from updating the same static variable x at the same time. public class DataRace implements Runnable { static volatile int x; public synchronized void run() { for (int i = 0; i < 10000; i++) { x++; x--; } } public static void main(String[] args) throws Exception { Thread [] threads = new Thread[100]; for (int i = 0; i < threads.length; i++) threads[i] = new Thread(new DataRace()); for (int i = 0; i < threads.length; i++) threads[i].start(); for (int i = 0; i < threads.length; i++) threads[i].join(); System.out.println(x); // x not always 0! } } Since we cannot synchronize on x (because it is primitive), the best solution I can think of is to create a new static object like static String lock = ""; and enclose the x++ and x-- within a synchronized block, locking on lock. But this seems really awkward. Is there a better way?

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  • Rails - Beginner wants feedback on how they've modeled their app and how to do it better.

    - by adam
    I think the way I've modelled my app is a bit fishy and i need to rejig things, im just not sure how. I've already re-jigged and refactored before. It took a long time ( I'm a beginner ) and I'm hesitant to it again in case i head off in the wrong direction again. Basic Idea, user can submit an answer, another user can mark it correct or incorrect. If incorrect they have to write the correct answer. Users can view their and everybody else's correct and incorrect answers. So I did it this way class Answer has_one: correction end class Correction belongs_to :answer end when a user marks an answer as correct, I set checked_at:DateTime and checked_by_id:integer on the Answer object to keep track of who checked the answer and when. For incorrect answers I create a correction object which holds the correct answer and again checked_by and checked_at details. I don't like this because I have checked_by and checked_at in both models. It just doesn't sit right. Possible solutions are: Create a third model such as VerifiedAnswer and move the checked_by/at attributes to that. It will handle the situtation where an answer is marked correct. Or are these models thin enough (they dont have any other attributes) that I can just have one model ( Answer ) that has all the attributes to store all this information?

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  • Need help managing MySql connections

    - by David Jenings
    I'm having trouble finding a clear explanation of connection pooling. I'm building an app using the .NET connector I downloaded from mysql.com. The app only needs one db connection but will be running simultaneously on about 6 machines on my network. Normally, I'd create the connection at startup and just leave it. But I'm seeing lots of posts from people who say that's bad practice. Also I'm concerned about timeouts. My app will run 24/7 and there may be extended periods without database activity. I'm leaning toward the following: using (MySqlConnection conn = new MySqlConnection(connStr)) { conn.Open(); // use connection } But I'm not sure I understand what's going on in the background. Is this actually closing the connection and allowing gc to kill the object, or is there a built in pooling behavior that preserves the object and redelivers it the next time I try to create one? I certainly don't want the app reauthenticating across the network every time I hit the database. Can anyone offer me some advise?

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  • [C++] Parent-Child scheme

    - by rubenvb
    I'm writing a class that holds a pointer to a parent object of the same type (think Qt's QObject system). Each object has one parent, and the parent should not be destroyed when a child is destroyed (obviously). class MyClass { public: MyClass(const MyClass* ptr_parent): parent(parent){}; ~MyClass(){ delete[] a_children; }; private: const MyClass* ptr_parent; // go to MyClass above MyClass* a_children; // go to MyClass below size_t sz_numChildren; // for iterating over a_children } (Excuse my inline coding, it's only for brevity) Will destroying the "Master MyClass" take care of all children? No child should be able to kill it's parent, because I would then have pointers in my main program to destroyed objects, correct? Why might you ask? I need a way to "iterate" through all subdirectories and find all files on a platform independent level. The creation of this tree will be handled by native API's, the rest won't. Is this a good idea to start with? Thanks!

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