Search Results

Search found 11936 results on 478 pages for 'objects'.

Page 357/478 | < Previous Page | 353 354 355 356 357 358 359 360 361 362 363 364  | Next Page >

  • what's the right way to do polymorphism with protocol buffers?

    - by user364003
    I'm trying to long-term serialize a bunch of objects related by a strong class hierarchy in java, and I'd like to use protocol buffers to do it due to their simplicity, performance, and ease of upgrade. However, they don't provide much support for polymorphism. Right now, the way I'm handling it is by having a "one message to rule them all" solution that has a required string uri field that allows me to instantiate the correct type via reflection, then a bunch of optional fields for all the other possible classes I could serialize, only one of which will be used (based on the value of the uri field). Is there a better way to handle polymorphism, or is this as good as I'm going to get?

    Read the article

  • Does invoking System.gc() in java suggest garbage collection of the tenured generation as well as th

    - by Markus Jevring
    When invoking System.gc() in java (via JMX), it will dutifully (attempt to) clean the young generation. This generally works very well. I have never seen it attempt to clean the tenured generation, though. This leads me to two questions: Can the tenured generation even be collected (i.e. is there actually garbage in this generation, or do all objects in the tenured generation actually still have live references to them)? If the tenured generation can be collected, can this be done via System.gc(), or is there another way to do it (unlikely), or will I simply have to wait until I run out of space in the tenured generation?

    Read the article

  • Do fields need to be explicitly final to have a "proper" immutable object?

    - by Yishai
    You often read about immutable objects requiring final fields to be immutable in Java. Is this in fact the case, or is it simply enough to have no public mutability and not actually mutate the state? For example, if you have an immutable object built by the builder pattern, you could do it by having the builder assign the individual fields as it builds, or having the builder hold the fields itself and ultimately return the immutable object by passing the values to its (private) constructor. Having the fields final has the obvious advantage of preventing implementation errors (such as allowing code to retain a reference to the builder and "building" the object multiple times while in fact mutating an existing object), but having the Builder store its data inside the object as it is built would seem to be DRYer. So the question is: Assuming the Builder does not leak the Object early and stops itself from modifying the object once built (say by setting its reference to the object as null) is there actually anything gained (such as improved thread safety) in the "immutability" of the object if the object's fields were made final instead?

    Read the article

  • unit testing methods with arrays as argument

    - by Ryan
    I am porting over some C++ assembly to VB that performs demodulation of various waveforms. I decided to go the unit test route instead of building a test app to get a feel for how testing is performed. The original demodulation code accepts an array that is the waveform along with some other arguments. How should one go about performing a test on something that has an array as an argument? Is it acceptable to generate fake data in a file and read it in at the beginning of the test? On a side note - The original C++ code was written because we were performing math that we couldn't do in VB6 so we had to cross boundaries between C++ and VB6 and arrays were used. Is there a "better" way of handling large amounts of data in the .NET world that us VB6 programmers may not yet be privy to? Or if we aren't crossing that managed/un-managed boundary, should we be representing our data as objects instead? Thanks all!

    Read the article

  • Offsite data storage for simple app, or a similar supported persistence mechanism?

    - by jdk
    Question Is there a usable facebook entry point to the Data Storage API that facebook lists on their app admin page for developers, or should I consider an alternate mechanism? What alternative mechanisms exist to simply persist my information offsite (away from my server app) without stuffing it into a cookie that's prone to expire? ... Background The facebook Data Store Admin tool is made available in a facebook App's Settings as seen here: (continue reading below) However when I visit the DataStoreAdmin link nothing works (i.e. clicking the buttons to define the data store types and objects does nothing - I have tried different browsers). The Wiki page for Data Store API hasn't been updated recently and the second last update says the beta Data Store was taken offline. It seems odd the link would be readily available and highly visible at the top of the App configuration area if indeed it's defunct. I was hoping some kind of key/value pair solution to remove the data calls from my own server.

    Read the article

  • (conditional) Multiple Event Handlers C#

    - by gjk
    A portion of my program requires a "flag" retrieval, that is I am fetching a value that is either True or False, and based on this return value two things could follow. 1) The flag is true, aka "go ahead", and I retrieve data from a database. 2) The flag is false, and I want to prevent the data from being retrieved. Now, this check has to be performed before any function that would call upon the database in question. I decided to implement this check in the form of an event handler attached to GUI objects that would trigger this data inquiry. This check event handler is called first upon necessary events, and my question is: How do I stop subsequent event handlers from firing if the FIRST event handler (my flag checker) comes up FALSE? Thanks

    Read the article

  • Creating a JSONRepresentation of my NSDictionary messes up the order?

    - by Lewion
    Hi all, To pass data to my webservice, I create an NSDictionary with the objects and keys I need, and use JSONRepresentation to format it nicely so I can post it to my service. It all worked fine with the previous version where only 2 parameters were required. An array with listitems, and a UDID. No I also need to pass a version number because we need to provide more data for people with the application at this new version. Only problem is when I create my JSONRepresentation now, the order of things are all messed up. NSMutableDictionary *rowDict = [[NSMutableDictionary alloc] initWithObjectsAndKeys:arrayDict,@"basketListV2",sharedData.udid,@"UDID",@"1.4",@"version",nil]; It prints out version first, then UDID and then basketListV2. Anyone know what I can do to maintain the order of my NSDict? I tried both NSDictionary and NSMutableDictionary (Probably doesn't have to do anything with it but for testing purposes I had to try it.) Thanks in advance. Lewion

    Read the article

  • Why does the assignment operator return a value and not a reference?

    - by Nick Lowman
    I saw the example below explained on this site and thought both answers would be 20 and not the 10 that is returned. He wrote that both the comma and assignment returns a value, not a reference. I don't quite understand what that means. I understand it in relation to passing variables into functions or methods i.e primitive types are passed in by value and objects by reference but I'm not sure how it applies in this case. I also understand about context and the value of 'this' (after help from stackoverflow) but I thought in both cases I would still be invoking it as a method, foo.bar() which would mean foo is the context but it seems both result in a function call bar(). Why is that and what does it all mean? var x = 10; var foo = { x: 20, bar: function () {return this.x;} }; (foo.bar = foo.bar)();//returns 10 (foo.bar, foo.bar)();//returns 10

    Read the article

  • Why can't I register a custom model binder for a List<int>?

    - by quarksoup
    I have an action that looks like public ActionResult GetUsers(List<int> userIds) {//do stuff} The list of userIds can become quite long, so I want to use Json.Net to deserialize it. To do so I created an IModelBinder implementation, which works fine for other objects, but never gets called for a List. The IModelBind looks like this public class JsonBinder : System.Web.Mvc.IModelBinder { public object BindModel(System.Web.Mvc.ControllerContext controllerContext, System.Web.Mvc.ModelBindingContext bindingContext) { //Do model binding stuff using Json.Net } } And I register this model binder with this line ModelBinders.Binders.Add(typeof(List<int>), new JsonBinder()); However the JsonBinder is never called. Why is this? Should I be using a ValueProvider?

    Read the article

  • WPF Binding to Items within a collection? (or converter with parameters)

    - by Sonic Soul
    i am using a WPF DataGrid, and in my Details row, i would like to show separate objects within a sub collection of each grid item. Is it possible to have a finer control of Path? for example something like... Path=SubCollection['ItemX'] etc.. also, if i was to use a converter, i don't want to have to create a separate converter for each item.. so would there be a way to supply a parameter to a converter that could than determine which collection item to return??

    Read the article

  • Deserialize Xml with empty elements in C#

    - by user204086
    Trying to deserialize some xml snippits into objects. The problem is that I'm getting an invalid format on every empy element tag. I can deserialize the object no problem when all of the elements have values. Or the empty elements are ommitted. Xml Snippit: <foo><propOne>1</propOne><propTwo /></foo> C# Class: [Serialilbe()] public class foo { public foo(){} [XmlElementAttribute(IsNullable = true)] public int? propOne {get;set;} [XmlElementAttribute(IsNullable = true)] public int? propTwo {get;set;} } Is there a setting on the class I can make to adjust the parsing? or Is there an easy way I can apply xsl to remove these elements? or Should I use regEx to remove the empty elements be fore desrializing? or an even better way?

    Read the article

  • how to access a different movieclip within the flash in AS3

    - by Pieter888
    I've been trying to learn Action Script 3 the past few weeks, making tiny interactive games to learn the basics. I stumble upon a problem every now and then but most of the times google helps me out. But this problem has got me stuck so please help: The main stage contains two objects(movieclips), the player and a wall. The player has got his own code so when I drag in the player object I don't have to write any code into the main stage to be able to move the player. This all worked pretty well and I now wanted to add the wall so the player actually has something to bounce into. Now here is the problem, I want to check if the player touches the wall, I've done this before but that was when I used the main stage as my coding playground instead of putting the code in movieclips. How can I check if the player hits the wall within the movement code of the player object?

    Read the article

  • Why are Objective-C instance variables declared in an interface?

    - by Chase
    I'm just getting into Objective-C (Java is my primary OO language). Defining an object's instance variables in the interface instead of the class seems strange. I'm used to an interface being a public API definition with nothing besides method signatures (not counting constants here). Is there some reason that state is defined in an interface (even if it is private) and behaviour is defined in a class. It just seems odd that since objects are state+behavior that the definition would be split into two separate places. Is it a design benefit is some way? A pain in the rear issue that you are just forced to deal with in Objective-C? A non-issue, just different? Any background on why it's done this way? Or can you put object state in a class and I just haven't hit that part in my book yet?

    Read the article

  • Adapting Map Iterators Using STL/Boost/Lambdas

    - by John Dibling
    Consider the following non-working code: typedef map<int, unsigned> mymap; mymap m; for( int i = 1; i < 5; ++i ) m[i] = i; // 'remove' all elements from map where .second < 3 remove(m.begin(), m.end(), bind2nd(less<int>(), 3)); I'm trying to remove elements from this map where .second < 3. This obviously isn't written correctly. How do I write this correctly using: Standard STL function objects & techniques Boost.Bind C++0x Lambdas I know I'm not eraseing the elements. Don't worry about that; I'm just simplifying the problem to solve.

    Read the article

  • Adobe After Efects Plugin With Cocoa (Overriding malloc)

    - by mustISignUp
    Messing about a bit, i have a working Adobe After Effects plugin with a bit of Obj-c / Cocoa in it (NSArray and custom objects - not ui stuff). The SDK guide states:- Always use After Effects memory allocation functions. In low-memory conditions (such as during RAM preview), it’s very important that plug-ins not compete with After Effects for OS memory, and deal gracefully with out-of-memory conditions. Failing to use our functions can cause lock-ups, crashes, and tech support calls. Don’t do that. If you’re wrapping existing C++ code, overloading new and delete to use our functions will save substantial reimplementation. On Windows, derive all classes from a common base class which implements new and delete. so my question.. is something compatible with the above statement possible in Obj-c?

    Read the article

  • How to use .DefaultListCellRenderer

    - by loddn
    First, i'm new at Java-programming and my native lang is not english, but still i hope to get some help from you all. What I try to do is a simple java-interface with a jComboBox and a jList. I want to poplate to jComboBox with Object-names and when the user select one of the names get the object-id which i will use to populate the jList. It's probably simple but i have bin stuck with this problem all day. private void loadComboBox() { biz.Object object = new biz.Object(); try { ArrayList<biz.Object> arrayOfObjects= object.getAllObjects();// ArrayList of objects for (biz.Object o:arrayOfObjects) { if (o != null) cbm.addElement(o); //`toString-method } cb.setModel(cbm); //JComboBox

    Read the article

  • How do I compare vectors in C++?

    - by Sam Phelps
    I am trying to compare two vector objects, and return a single vector containing all the chars which appear in both vectors. How would I go about this without writing some horribly complex manual method which compares every char in the first vector to every char in the second vector and using an if to add it to a third vector (which would be returned) if they match. Maybe my lack of real experience with vectors is making me imagine this will be harder than it really is, but I suspect there is some simplier way which I have been unable to find through searching.

    Read the article

  • Django query - join on the same table

    - by dana
    i have a mini blog app, and a 'timeline' . there i want to be displayed all the posts from all the friends of a user, plus the posts of that user himself. For that, i have to make some kind of a 'join' between the results of two queries (queries on the same table) , so that the final result will be the combination of the user - posesor of the account, and all his friends. My query looks like this: blog = New.objects.filter(created_by = following,created_by = request.user) By that ',' i wanted to make a 'join' -i found something like this on a doc- but this method is not correct- i'm getting an error. How else could be done this 'join' ? Thanks!

    Read the article

  • How to change the value of progressbar in C#?

    - by shekhar
    Hi, I want to add an progress bar into my C# based application. I would like to know what is the good way of updating its value at particular events? My problem is, I have single function in UI which does all the processing.This function in turn calls many more functions, creates objects, updates database, etc. (basically performs all the work) and returns values in an output file. I have access to that function only. So in this how to update the progressbar's value at the end of each step? What is the best practice for this kind of situation? What is the good way to keep UI logic and business logic seperate? I want to avoid writting progressbar related code in my library code. Please suggest some solution. Thanks and Regards,

    Read the article

  • Rails - How to secure foreign keys and still allow association selection

    - by Bryce
    For simplicity, assume that I have a simple has-many-through relationship class User < ActiveRecord::Base has_many :courses, :through => :registrations end class Registration < ActiveRecord::Base belongs_to :user belongs_to :course end class Course < ActiveRecord::Base has_many :users, :through => :registrations end I want to keep my app secure, so I use attr_accessible to whitelist my attributes. My question is twofold: How would I set up my whitelist attributes such that I could create a new Registration object through a form (passing in :user and :course, but not risk allowing those foreign keys to be maliciously updated later? How would I set up my validations such that both belongs_to associations are required BUT also allow for Registration objects to be created in nested forms?

    Read the article

  • "Passing Go" in a (python) date range

    - by anonymous coward
    The Rules: An employee accrues 8 hours of Paid Time Off on the day after each quarter. Quarters, specifically being: Jan 1 - Mar 31 Apr 1 - Jun 30 Jul 1 - Sep 30 Oct 1 - Dec 31 The Problem Employees will use an automated system to request paid time off, possibly occurring in the past, as well as the future. Requests should only be accepted if the employee has (or will have) that time available. For instance, if an employee only has 1 Day of Paid Time Off currently available (currently being January 20th), but is requesting 2 Days of Paid Time Off, beginning September 20th, the system should take into account that the employee would have accrued enough time off by then and allow the request. (Obviously ignoring that the employee may use up existing time before that date). I'm currently using Python, and wondering what the correct approach to something like this would be. I'm assuming that using DateTime objects, and possibly the dateutil module, would help here, but my brain isn't wrapping around this problem for some reason.

    Read the article

  • Can't get a List(Of <my class>) from a Dictionary in .NET?

    - by magsto
    I have a Dictionary with key of type UInteger and the value is List(Of Session) where the (Public) class Session contains a couple of variables and a constructor (Public Sub New(...)). Some of the variables in my Session class is: Private count As Integer Private StartDate As Date Private Values As List(Of Integer) and a couple of methods like: Friend Sub Counter(ByVal c as Integer) count += c End Sub There is no problem to add values to the Dictionary: Dim Sessions As New List(Of Session) Dim dict As New Dictionary(Of Integer, Sessions) then some code to fill up a couple of Session objects in Sessions (not shown here) and then: dict.Add(17, Sessions) 'No problem Sessions.Clear() Sessions = dict(17) 'This doesn't return anything! The Sessions object is empty even if the code doesn't returned any error. Is my class Session to compex to be stored in a Dictionary?

    Read the article

  • Passing Session[] and Request[] to Methods in C#

    - by NYARROW
    In C#, How do you pass the Session[] and Request[] objects to a method? I would like to use a method to parse out Session and Request paramaters for a .aspx page to reduce the size of my Page_Load method. I am passing quite a few variables, and need to support both POSTand GET methods. For most calls, not all variables are present, so I have to test every variable multiple ways, and the code gets long... This is what I am trying to do, but I can't seem to properly identify the Session and Request paramaters (this code will not compile, because the arrays are indexed by number) static string getParam( System.Web.SessionState.HttpSessionState[] Session, System.Web.HttpRequest[] Request, string id) { string rslt = ""; try { rslt = Session[id].ToString(); } catch { try { rslt = Request[id].ToString(); } catch { } } return rslt; } From Page_Load, I want to call this method as follows to retrieve the "MODE" paramater: string rslt; rslt = getParam(Session, Request, "MODE"); Thanks!

    Read the article

  • Recommand a Perl module to persist a large object for re-use between runs?

    - by Alnitak
    I've got a large XML file, which takes 40+ seconds to parse with XML::Simple. I'd like to be able to cache the resulting parsed object so that on the next run I can just retrieve the parsed object and not reparse the whole file. I've looked at using Data::Dumper but the documentation is a bit lacking on how to store and retrieve its output from disk files. Other classes I've looked at (e.g. Cache::Cache) appear designed for storage of many small objects, not a single large one. Can anyone recommend a module designed for this?

    Read the article

  • ActionScript - Automatic containment and repositioning of object bounds

    - by TheDarkIn1978
    when adding objects arbitrarily to the stage with mouse clicks, is there a more simple way to making sure the object's bounds do not exceed those of the stage? currently i'm calling something like this before adding the object to the display list: var newSwatchRect:Rectangle = newSwatch.getBounds(this); if (newSwatchRect.x < stage.x) {newSwatchRect.x = stage.x;} if (newSwatchRect.y < stage.y) {newSwatchRect.y = stage.y;} if (newSwatchRect.x + newSwatchRect.width > stage.stageWidth) {newSwatchRect.x = stage.stageWidth - newSwatchRect.width;} if (newSwatchRect.y + newSwatchRect.height > stage.stageHeight) {newSwatchRect.y = stage.stageHeight - newSwatchRect.height;}

    Read the article

< Previous Page | 353 354 355 356 357 358 359 360 361 362 363 364  | Next Page >