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  • Design Anti-Patterns - C# - Do you call this a God object?

    - by Reddy S R
    I am writing Portfolio module for my web site and it has 3 components. Gallery Category, Gallery, & Gallery Images. I am doing all the request handling, (creating, reading, updating, other), for the above 3 components in 1 class, Portfolio. DB handling jobs for Portfolio module is done in another file. My question is, even just for request handling purpose, can you do all the operations in 1 class? -Reddy

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  • Why does IE8 change flash callback function into object?

    - by Christian Hollbaum
    Hi Guys I have put 2 swf's (using swfobject 2) on the same website; One for playing a movie, and one for controlling the movie (I want to position them seperately, so they can't be in the same swf). I'm doing the communication between the two using javascript with jQuery, and externalcallback functions in both swf's. Everything is running smoothly on all browsers, but IE8. In IE8 I can only call the pause callback function in the control swf once. When it has been called it will not run properly the next time. After trying to debug what is happening live, using javascript's "type of" I have found that IE8 changes the callback function on the flash object from a function into an object when it has been triggered. Can anyone explain why this is happening? .. and maybe suggest how to avoid this? .. or change the object back to a function?

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  • How to store an object in Riak with the Java client?

    - by Jonas
    I have setup Riak on a Ubuntu machine, and it seam to work if I do riak ping. Now I would like to use the Riak Java client to store an object, but it doesn't work. I get com.basho.riak.client.response.RiakIORuntimeException when I try to store an object. What am I doing wrong? Is there a way to test if I can access riak from my java client? Do I have to create a Bucket first? how? import com.basho.riak.client.RiakClient; import com.basho.riak.client.RiakObject; import com.basho.riak.client.response.FetchResponse; public class RiakTest { public static void main(String[] args) { // connect RiakClient riak = new RiakClient("http://192.168.1.107:8098/riak"); // create object RiakObject o = new RiakObject("mybucket", "mykey", "myvalue"); // store riak.store(o); } }

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  • What are the cons of using DrawableGameComponent for every instance of a game object?

    - by Kensai
    I've read in many places that DrawableGameComponents should be saved for things like "levels" or some kind of managers instead of using them, for example, for characters or tiles (Like this guy says here). But I don't understand why this is so. I read this post and it made a lot of sense to me, but these are the minority. I usually wouldn't pay too much attention to things like these, but in this case I would like to know why the apparent majority believes this is not the way to go. Maybe I'm missing something.

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  • Iterate through a DataTable to find elements in a List object?

    - by Darth Continent
    As I iterate through a DataTable object, I need to check each of its DataRow objects against the items in a generic string List. I found a blog post using the List's Find method along with a delegate, but whereas that example has a separate class (Person), I'm attempting something like the following using an instance of the string object: // My definition of the List object. List<string> lstAccountNumbers = new List<string>(); ... // I populate the List via its Add method. ... foreach (DataRow drCurrentRow in dtMyDataTable.Rows) { if (lstAccounts.Find(delegate(string sAccountNumber) { return sAccountNumber == drCurrentRow["AccountNumber"]; }) { Found_DoSomething(); } else { NotFound_DoSomethingElse(); } } However, with this syntax I'm receiving "Cannot implicitly convert type 'string' to 'bool'" for the if block. Could someone please clarify what I'm doing wrong and how best to accomplish what I'm trying to do?

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  • How to salvage SQL server 2008 query from KILLED/ROLLBACK state?

    - by littlegreen
    I have a stored procedure that inserts batches of millions of rows, emerging from a certain query, into an SQL database. It has one parameter selecting the batch; when this parameter is omitted, it will gather a list of batches and recursively call itself, in order to iterate over batches. In (pseudo-)code, it looks something like this: CREATE PROCEDURE spProcedure AS BEGIN IF @code = 0 BEGIN ... WHILE @@Fetch_Status=0 BEGIN EXEC spProcedure @code FETCH NEXT ... INTO @code END END ELSE BEGIN -- Disable indexes ... INSERT INTO table SELECT (...) -- Enable indexes ... Now it can happen that this procedure is slow, for whatever reason: it can't get a lock, one of the indexes it uses is misdefined or disabled. In that case, I want to be able kill the procedure, truncate and recreate the resulting table, and try again. However, when I try and kill the procedure, the process frequently oozes into a KILLED/ROLLBACK state from which there seems to be no return. From Google I have learned to do an sp_lock, find the spid, and then kill it with KILL <spid>. But when I try to kill it, it tells me SPID 75: transaction rollback in progress. Estimated rollback completion: 0%. Estimated time remaining: 554 seconds. I did find a forum message hinting that another spid should be killed before the other one can start a rollback. But that didn't work for me either, plus I do not understand, why that would be the case... could it be because I am recursively calling my own stored procedure? (But it should be having the same spid, right?) In any case, my process is just sitting there, being dead, not responding to kills, and locking the table. This is very frustrating, as I want to go on developing my queries, not waiting hours on my server sitting dead while pretending to be finishing a supposed rollback. Is there some way in which I can tell the server not to store any rollback information for my query? Or not to allow any other queries to interfere with the rollback, so that it will not take so long? Or how to rewrite my query in a better way, or how kill the process successfully without restarting the server?

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  • What's the difference between IEquatable and just overriding Object.Equals() ?

    - by devoured elysium
    I want my Food class to be able to test whenever it is equal to another class. I will later use it against a List, and I want to use its List.Contains() method. Should I implement IEquatable or just override Object.Equals()? From MSDN: This method determines equality by using the default equality comparer, as defined by the object's implementation of the IEquatable.Equals method for T (the type of values in the list). So my next question is: which functions/classes of the .NET framework make use of Object.Equals()? Should I use it in the first place? Thanks

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  • Email Validation... advocating the use of +, and how embarrassed would you be to have written this?

    - by Langdon
    I take full advantage of GMail's wildcard feature ([email protected]). Unfortunately it seems that most developers don't understand that + is valid in an email address. This makes trying to unsubscribe a real chore sometimes. Take TicketMaster for example... immediately you notice that they didn't even bother escaping the email address, so the text field defaults to "user [email protected]". Not a problem, we can just add the + manually. Once Submit is clicked, you'll notice the validation stops you right in your tracks. What now? Most users would have to further contact TicketMaster and attempt to explain the situation. I opened up FireBug to investigate. That's when I noticed this whopping 74 line email validation function with so much redundancy it's ridiculous. My favorite check is on line 20, informing the user that his/her email cannot have more than one @. Unreal. My second favorite part is the TWO regular expressions used! Imagine... someone was paid money for this... and by the looks of it, they were paid by the line count. //Validates the email function validateOptoutEmail(object) { var emailStr = object.value; if(emailStr == '' || emailStr == null) { alert('Email can not be empty. Please provide email'); object.value = ''; object.focus(); return false; } else if(Trim(emailStr).length == 0) { alert('Email can not be empty. Please provide email'); object.value = ''; object.focus(); return false; } else { var atcount=0; for(var i=0;i<emailStr.length;i++) { if(emailStr.charAt(i)=='@') atcount++; } if(atcount>1) { alert('Invalid email. Email cannot have more than one @'); object.value = ''; object.focus(); return false; } if(emailStr.indexOf('.') == -1) { alert('Invalid email. Email must have one dot'); object.value = ''; object.focus(); return false; } if(emailStr.indexOf('..')!= -1) { alert('Invalid email. Email cannot have consecutive dots'); object.value = ''; object.focus(); return false; } var dotpos=0; for(var i=dotpos;i< emailStr.length;i++) { var ichar=emailStr.charAt(i); if(ichar=='.') dotpos=i; } for(var i=dotpos+1;i< emailStr.length;i++) { var ichar=emailStr.charAt(i); if((!isNaN(ichar)) || (ichar == '_')) { alert('Invalid email. Email cannot have numbers or _ after dot'); object.value = ''; object.focus(); return false; } } var pattern2=/^([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,4})+$/; var pattern1=/^[0-9a-zA-Z\-\_.]+@\w+([\.-]?\w+)*(\.\w{2,4})+$/; if (pattern1.test(emailStr)) { if(pattern2.test(emailStr)) { return true; } else { alert('Invalid email'); object.value = ''; object.focus(); } return true; } else { alert('Invalid email'); object.value = ''; object.focus(); return false; } alert('Invalid email'); object.value = ''; object.focus(); return false; } } I eventually just put a break point in FireBug and changed the value of the email address passed into the validation function. From there everything worked fine... All that said, how can we get the word out there that + is valid in an email address? Too often, I'm unable to use the email address that I want to use for certain web sites because developers simply aren't aware of what constitutes a valid email address.

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  • Lua and Objective C not running script.

    - by beta
    I am trying to create an objective c interface that encapsulates the functionality of storing and running a lua script (compiled or not.) My code for the script interface is as follows: #import <Cocoa/Cocoa.h> #import "Types.h" #import "lua.h" #include "lualib.h" #include "lauxlib.h" @interface Script : NSObject<NSCoding> { @public s32 size; s8* data; BOOL done; } @property s32 size; @property s8* data; @property BOOL done; - (id) initWithScript: (u8*)data andSize:(s32)size; - (id) initFromFile: (const char*)file; - (void) runWithState: (lua_State*)state; - (void) encodeWithCoder: (NSCoder*)coder; - (id) initWithCoder: (NSCoder*)coder; @end #import "Script.h" @implementation Script @synthesize size; @synthesize data; @synthesize done; - (id) initWithScript: (s8*)d andSize:(s32)s { self = [super init]; self->size = s; self->data = d; return self; } - (id) initFromFile:(const char *)file { FILE* p; p = fopen(file, "rb"); if(p == NULL) return [super init]; fseek(p, 0, SEEK_END); s32 fs = ftell(p); rewind(p); u8* buffer = (u8*)malloc(fs); fread(buffer, 1, fs, p); fclose(p); return [self initWithScript:buffer andSize:size]; } - (void) runWithState: (lua_State*)state { if(luaL_loadbuffer(state, [self data], [self size], "Script") != 0) { NSLog(@"Error loading lua chunk."); return; } lua_pcall(state, 0, LUA_MULTRET, 0); } - (void) encodeWithCoder: (NSCoder*)coder { [coder encodeInt: size forKey: @"Script.size"]; [coder encodeBytes:data length:size forKey:@"Script.data"]; } - (id) initWithCoder: (NSCoder*)coder { self = [super init]; NSUInteger actualSize; size = [coder decodeIntForKey: @"Script.size"]; data = [[coder decodeBytesForKey:@"Script.data" returnedLength:&actualSize] retain]; return self; } @end Here is the main method: #import "Script.h" int main(int argc, char* argv[]) { Script* script = [[Script alloc] initFromFile:"./test.lua"]; lua_State* state = luaL_newstate(); luaL_openlibs(state); luaL_dostring(state, "print(_VERSION)"); [script runWithState:state]; luaL_dostring(state, "print(_VERSION)"); lua_close(state); } And the lua script is just: print("O Hai World!") Loading the file is correct, but I think it messes up at pcall. Any Help is greatly appreciated. Heading

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  • Why, in WPF, do we set an object to Stretch via its Alignment properties instead of Width/Height?

    - by Jonathan Hobbs
    In WPF's XAML, we can tell an element to fill its container like this: <Button HorizontalAlignment="Stretch" VerticalAlignment="Stretch" /> Why is it that when we set an element to Stretch, we do it via the HorizontalAlignment and VerticalAlignment properties? Why did the WPF design team decide to take this approach over having Width="Stretch" and Height="Stretch"? I presume it was a calculated decision, and I'm curious about the reasoning. CSS, among other technologies, follows the convention that stretching is done via the width and height properties, and that alignment affects positioning exclusively. This seems intuitive enough: stretching the element is manipulating its width and height, after all! Using the corresponding alignment property to stretch an element seems counter-intuitive and unusual in comparison. This makes me think they didn't just pick this option for no reason: they made a calculated decision and had reasons behind it. Width and Height use the double data type, which would ordinarily mean assigning it a string would be silly. However, WPF's Window objects can take Width="Auto", which gets treated as double.NaN. Couldn't Width="Stretch" be stored as double.PositiveInfinity or some other value?

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  • SQL SERVER – Solution – User Not Able to See Any User Created Object in Tables – Security and Permissions Issue

    - by pinaldave
    There is an old quote “A Picture is Worth a Thousand Words”. I believe this quote immensely. Quite often I get phone calls that something is not working if I can help. My reaction is in most of the cases, I need to know more, send me exact error or a screenshot. Until and unless I see the error or reproduce the scenario myself I prefer not to comment. Yesterday I got a similar phone call from an old friend, where he was not sure what is going on. Here is what he said. “When I try to connect to SQL Server, it lets me connect just fine as well let me open and explore the database. I noticed that I do not see any user created instances but when my colleague attempts to connect to the server, he is able to explore the database as well see all the user created tables and other objects. Can you help me fix it? “ My immediate reaction was he was facing security and permission issue. However, to make the same recommendation I suggested that he send me a screenshot of his own SSMS and his friend’s SSMS. After carefully looking at both the screenshots, I was very confident about the issue and we were able to resolve the issue. Let us reproduce the same scenario and many there is some learning for us. Issue: User not able to see user created objects First let us see the image of my friend’s SSMS screen. (Recreated on my machine) Now let us see my friend’s colleague SSMS screen. (Recreated on my machine) You can see that my friend could not see the user tables but his colleague was able to do the same for sure. Now I believed it was a permissions issue. Further to this I asked him to send me another image where I can see the various permissions of the user in the database. My friends screen My friends colleagues screen This indeed proved that my friend did not have access to the AdventureWorks database and because of the same he was not able to access the database. He did have public access which means he will have similar rights as guest access. However, their SQL Server had followed my earlier advise on having limited access for guest access, which means he was not able to see any user created objects. My next question was to validate what kind of access my friend’s colleague had. He replied that the colleague is the admin of the server. I suggested that if my friend was suppose to have admin access to the database, he should request of having admin access to his colleague. My friend promptly asked for the same to his colleague and on following screen he added him as an admin. You can do the same using following T-SQL script as well. USE [AdventureWorks2012] GO ALTER ROLE [db_owner] ADD MEMBER [testguest] GO Once my friend was admin he was able to access all the user objects just like he was expecting. Please note, this complete exercise was done on a development server. One should not play around with security on live or production server. Security is such an issue, which should be left with only senior administrator of the server. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Security, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • JAVA: How to use paint() method to update the previously drawn object?

    - by GamDroid
    How to use paint() such that when repaint() is called the previously drawn object should not get deleted when drawing the new object. That is the drawing area must get UPDATED only and not REDRAWN. In my code when one of many button is clicked, some aplhabet get displayed. I want to have functionality such that when other buttons are clicked the previously drawn alhabets must be present.Take is as if a string of alphabets getting created as the buttons are clicked. Im using Java Swing for coding. Some piece of my code: if(source == btnAlpha[i] ) bollyDraw.repaint(); //bollydraw is an object of a JPanel extended class having implemented the paintComponent(Graphics g) method In the paint() method: if (word[i] == key) { g.drawChars(word, i, 1, x, y); }

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  • How to I serialize a large graph of .NET object into a SQL Server BLOB without creating a large bu

    - by Ian Ringrose
    We have code like: ms = New IO.MemoryStream bin = New System.Runtime.Serialization.Formatters.Binary.BinaryFormatter bin.Serialize(ms, largeGraphOfObjects) dataToSaveToDatabase = ms.ToArray() // put dataToSaveToDatabase in a Sql server BLOB But the memory steam allocates a large buffer from the large memory heap that is giving us problems. So how can we stream the data without needing enough free memory to hold the serialized objects. I am looking for a way to get a Stream from SQL server that can then be passed to bin.Serialize() so avoiding keeping all the data in my processes memory. Likewise for reading the data back... Some more background. This is part of a complex numerical processing system that processes data in near real time looking for equipment problems etc, the serialization is done to allow a restart when there is a problem with data quality from a data feed etc. (We store the data feeds and can rerun them after the operator has edited out bad values.) Therefore we serialize the object a lot more often then we de-serialize them. The objects we are serializing include very large arrays mostly of doubles as well as a lot of small “more normal” objects. We are pushing the memory limit on a 32 bit system and make the garage collector work very hard. (Effects are being made elsewhere in the system to improve this, e.g. reusing large arrays rather then create new arrays.) Often the serialization of the state is the last straw that courses an out of memory exception; our peak memory usage is while this serialization is being done. I think we get large memory pool fragmentation when we de-serialize the object, I expect there are also other problem with large memory pool fragmentation given the size of the arrays. (This has not yet been investigated, as the person that first looked at this is a numerical processing expert, not a memory management expert.) Are customers use a mix of Sql Server 2000, 2005 and 2008 and we would rather not have different code paths for each version of Sql Server if possible. We can have many active models at a time (in different process, across many machines), each model can have many saved states. Hence the saved state is stored in a database blob rather then a file. As the spread of saving the state is important, I would rather not serialize the object to a file, and then put the file in a BLOB one block at a time. Other related questions I have asked How to Stream data from/to SQL Server BLOB fields? Is there a SqlFileStream like class that works with Sql Server 2005?

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  • Adding an Object to Vector loses Reference using Java?

    - by thechiman
    I have a Vector that holds a number of objects. My code uses a loop to add objects to the Vector depending on certain conditions. My question is, when I add the object to the Vector, is the original object reference added to the vector or does the Vector make a new instance of the object and adds that? For example, in the following code: private Vector numbersToCalculate; StringBuffer temp = new StringBuffer(); while(currentBuffer.length() > i) { //Some other code numbersToCalculate.add(temp); temp.setLength(0); //resets the temp StringBuffer } What I'm doing is adding the "temp" StringBuffer to the numbersToCalculate Vector. Should I be creating a new StringBuffer within the loop and adding that or will this code work? Thanks for the help! Eric

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  • How to update control state in asp.net/ajax?

    - by darth_alexious
    I'm trying to update certain controls according to a selection in a dropdown list. For example, in the "selectedIndexChanged" event of a dropDownList, if a user selects the value "sport-car" the text box "payload" is disabled and the textbox "max speed" is enabled. private sub dropDownList1_SelectedIndexChanged(byval sender as object, byval e as eventargs) handles dropDownList1.SelectedIndexChanged If dropDownList1.selectedValue = "sport-car" then textBox_payLoad.enabled = false textBox_maxSpeed.enabled = true end if end sub When I'm doing something like this, the controls aren't enabled/disabled, even the event (wich I've added a breakpoint) seems not to be raised (sometimes several time after it is raised). Also, when the instructions in the condition is executed, nothing changes. What am I doing wrong? Maybe this is a very easy issue, but I'm a begginer in MS Visual Web Developer.

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  • ASP.NET Web Service - Passing a base object with list/collection?

    - by schooner
    We need to create a simple web service in ASP.NET that can be called from PHP or other languages. This in turn will be used to update records in a database for an item submission. The core part is fairly simple, we have a base set of fields for the object - first name, last name, birth date, city, etc. In addition however we need to accept a list of items associated with that object that can range from 0-n. Jan 1 2009, ABC May 1 2010, 123 Jun 30 2010, XXXXX What would be the best way to structure this so it can be easily passed to the ASP.NET web service and processed as a single call for the entire object? Would passing the list of items as a single delimted string be a wise approach? Ex: Jan 1 2009, ABC|May 1 2010, 123|Jun 30 2010, XXXXX

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  • Detailed C++ book for a programmer already familiar with C and object-oriented programming?

    - by Anto
    I know (to some extent) a few languages, including C, Java and Python. I'm also (somewhat) familiar with Scala and Scheme, plus I can read (but not write) x86 Assembly. Say I want to learn C++, what is a good book which doesn't try to teach me what a class is, teach me inheritance, polymorphism or loosely coupled classes again, nor does try to teach me other basics, just the C++ language (as well as how to write idiomatic C++ code, not e.g. Java with C++ syntax) and its standard library? Note: "Detailed" as used in the title means that it doesn't try to cover C++ in 100 pages, I want to know the details of the language. Of course, mastery comes from practice, but I don't want to learn just a little bit of C++ from the book, but learn it quite thoroughly.

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  • Why is the event object different coming from jquery bind vs. addEventListener

    - by yodaisgreen
    Why is it when I use the jQuery bind the event object I get back is different from the event object I get back using addEventListener? The event object resulting from this jQuery bind does not have the targetTouches array (among other things) but the event from the addEventListener does. Is it me or is something not right here? $(document).ready (function () { $("#test").bind("touchmove", function (event) { console.log(event.targetTouches[0].pageX); // targetTouches is undefined }); }); vs. $(document).ready (function () { var foo = document.querySelectorAll('#test') foo[0].addEventListener('touchmove', function (event) { console.log(event.targetTouches[0].pageX); // returns the correct values }, false); });

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  • How can I modify a custom object in an ASP.NET FormView based on a button click?

    - by David
    I have a FormView that modifies an instance of a custom class. The various form controls (TextBox, DropDownList etc.) are working fine. However, I want to include a Button that will modify the state of the DataItem based on some very simple logic. There is no form control which could control this change in a non-confusing way. So I tried adding a Button and modifying the state of the DataItem in the code-behind. But the problem I encounter is that the FormView's DataItem is null/nothing. From reading this SO question it seems the problem is that the item is not databound when the Button's Click event is fired. So, the question; Is it possible to get the DataItem for the FormView during a Button's Click event? and if not: what are my options for implementing this? Thanks in advance. Edit: I can include any code that might help

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  • How to do dependency Injection and conditional object creation based on type?

    - by Pradeep
    I have a service endpoint initialized using DI. It is of the following style. This end point is used across the app. public class CustomerService : ICustomerService { private IValidationService ValidationService { get; set; } private ICustomerRepository Repository { get; set; } public CustomerService(IValidationService validationService,ICustomerRepository repository) { ValidationService = validationService; Repository = repository; } public void Save(CustomerDTO customer) { if (ValidationService.Valid(customer)) Repository.Save(customer); } Now, With the changing requirements, there are going to be different types of customers (Legacy/Regular). The requirement is based on the type of the customer I have to validate and persist the customer in a different way (e.g. if Legacy customer persist to LegacyRepository). The wrong way to do this will be to break DI and do somthing like public void Save(CustomerDTO customer) { if(customer.Type == CustomerTypes.Legacy) { if (LegacyValidationService.Valid(customer)) LegacyRepository.Save(customer); } else { if (ValidationService.Valid(customer)) Repository.Save(customer); } } My options to me seems like DI all possible IValidationService and ICustomerRepository and switch based on type, which seems wrong. The other is to change the service signature to Save(IValidationService validation, ICustomerRepository repository, CustomerDTO customer) which is an invasive change. Break DI. Use the Strategy pattern approach for each type and do something like: validation= CustomerValidationServiceFactory.GetStratedgy(customer.Type); validation.Valid(customer) but now I have a static method which needs to know how to initialize different services. I am sure this is a very common problem, What is the right way to solve this without changing service signatures or breaking DI?

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  • Would this hack for per-object permissions in django work?

    - by Edward
    According to the documentation, a class can have the meta option permissions, described as such: Options.permissions Extra permissions to enter into the permissions table when creating this object. Add, delete and change permissions are automatically created for each object that has admin set. This example specifies an extra permission, can_deliver_pizzas: permissions = (("can_deliver_pizzas", "Can deliver pizzas"),) This is a list or tuple of 2-tuples in the format (permission_code, human_readable_permission_name). Would it be possible to define permissions at run time by: permissions = (("can_access_%s" % self.pk, / "Has access to object %s of type %s" % (self.pk,self.__name__)),) ?

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  • Need a .NET Dictionary<string,object> with just a little more functionality.

    - by Ronnie Overby
    I need a dictionary but I also need to store a boolean value about the object in the dictionary. What's the best way for this. Something like Dictonary<string,object,bool> would be ideal, but doesn't exist. My first idea was: public class SomeObject { public object Value { get; set; } public bool Flag { get; set; } } // and then use: Dictionary<string,SomeObject> myDictionary; My 2nd idea was to implement IDictionary and contain two dictionaries within that were manipulated by the implemented methods and property accessors. My 3rd idea was to see what the folks at StackOverflow would do.

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  • C-states and P-states : confounding factors for benchmarking

    - by Dave
    I was recently looking into a performance issue in the java.util.concurrent (JUC) fork-join pool framework related to particularly long latencies when trying to wake (unpark) threads in the pool. Eventually I tracked the issue down to the power & scaling governor and idle-state policies on x86. Briefly, P-states refer to the set of clock rates (speeds) at which a processor can run. C-states reflect the possible idle states. The deeper the C-state (higher numerical values) the less power the processor will draw, but the longer it takes the processor to respond and exit that sleep state on the next idle to non-idle transition. In some cases the latency can be worse than 100 microseconds. C0 is normal execution state, and P0 is "full speed" with higher Pn values reflecting reduced clock rates. C-states are P-states are orthogonal, although P-states only have meaning at C0. You could also think of the states as occupying a spectrum as follows : P0, P1, P2, Pn, C1, C2, ... Cn, where all the P-states are at C0. Our fork-join framework was calling unpark() to wake a thread from the pool, and that thread was being dispatched onto a processor at deep C-state, so we were observing rather impressive latencies between the time of the unpark and the time the thread actually resumed and was able to accept work. (I originally thought we were seeing situations where the wakee was preempting the waker, but that wasn't the case. I'll save that topic for a future blog entry). It's also worth pointing out that higher P-state values draw less power and there's usually some latency in ramping up the clock (P-states) in response to offered load. The issue of C-states and P-states isn't new and has been described at length elsewhere, but it may be new to Java programmers, adding a new confounding factor to benchmarking methodologies and procedures. To get stable results I'd recommend running at C0 and P0, particularly for server-side applications. As appropriate, disabling "turbo" mode may also be prudent. But it also makes sense to run with the system defaults to understand if your application exhibits any performance sensitivity to power management policies. The operating system power management sub-system typically control the P-state and C-states based on current and recent load. The scaling governor manages P-states. Operating systems often use adaptive policies that try to avoid deep C-states for some period if recent deep idle episodes proved to be very short and futile. This helps make the system more responsive under bursty or otherwise irregular load. But it also means the system is stateful and exhibits a memory effect, which can further complicate benchmarking. Forcing C0 + P0 should avoid this issue.

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  • Why Is my json-object from AJAX not understood by javascript, even with 'json' dataType?

    - by pete
    My js code simply gets a json object from my server, but I think it should be automatically parsed and turned into an object with properties, yet it's not allowing access properly. $.ajax({ type: 'POST', url: '/misc/json-sample.js', data: {href: path}, // THIS IS THE POST DATA THAT IS PASSED IN TO THE DRUPAL MENU CALL TO GET THE MENU... dataType: 'json', success: function (datax) { if (datax.debug) { alert('Debug data: ' + datax.debug); } else { alert('No debug data: ' + datax.toSource() ) ; } The /misc/json-sample.js file is: [ { "path": "examplemodule/parent1/child1/grandchild1", "title": "First grandchild option", "children": false } ] (I have also been trying to return that object from drupal as follows, and the same results.) Drupal version of misc/json-sample.js: $items[] = array( 'path' = 'examplemodule/parent1/child1/grandchild1', 'title' = t('First grandchild option'), 'debug' = t('debug me!'), 'children' = FALSE ); print drupal_to_js($items); What happens (in FF, which has the toSource() capability) is the alert with 'No debug data: [ { "path": "examplemodule/parent1/child1/grandchild1", "title": "First grandchild option", "children": false } ] Thanks

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  • How can I call a method on a custom object created in JavaScript using C#?

    - by just in case
    I have a WebBrowser control. I have added some JavaScript into the head tag and I can see it is working as expected by adding an alert. Inside of this js I am creating a function and adding some members to it's prototype like so: function test() { } test.prototype.run = function() { alert('success!') } function createTest() { return new test() } Then back inside of C# I am doing: dynamic test = this.browser.InvokeScript("createTest"); test.run(); I can see that the test object is some ComObject but when I call run() nothing happens. I get no error but nothing happens. Does anyone know how to call this type of custom object? Also suppose I wanted to get rid of the createTest() method, how can I create a new instance of test from C#? Also, for bonus points, is there anything special I need to know about attaching events to this custom object (on say a 'complete' member) such that it will callback into my C# code?

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