Search Results

Search found 13788 results on 552 pages for 'instance'.

Page 346/552 | < Previous Page | 342 343 344 345 346 347 348 349 350 351 352 353  | Next Page >

  • Why isn't the "this." command needed in this constructor? (java)

    - by David
    I'm reading a book about java. It just got to explaining how you create a class called "deck" which contains an array of cards as its instance variable(s). Here is the code snippit: class Deck { Card[] cards; public Deck (int n) { cards = new Card[n]; } } why isn't the this. command used? for example why isn't the code this: class Deck { Card[[] cards; public Deck (int n) { this.cards = new Card[n]; } }

    Read the article

  • Storing users in a database

    - by EMcKenna
    Im wondering whats the best way of storing different types of users in my database. I am writing an application that has 4 main user types (admin, school, teacher, student). At the moment I have a table for each of these but i'm not sure thats the best way of storing user information. For instance... Allowing students to PM other student is simple (store sender and receiver student_id) but enabling teachers to PM students requires another table (sender teacher_id, sender student_id). Should all users be stored in one users table with a user_type field? If so, the teacher / student specific information will still have to be stored in another table. users user_id, password_hash, user_type students user_id, student_specific_stuff... teachers user_id, teacher_specific_stuff... How do I stop a user who has a user_type = student from being accidentally being entered into the teachers table (as both have a user_id) Just want to make sure I get the database correct before i go any further. Thanks...

    Read the article

  • Getting the location in Android programatically

    - by steveo225
    I know this has been asked a ton, so my apologies. I have the following code, and cannot get the location, always a null response. I am trying to avoid a LocationListener in this instance because I am already using an update Service, and the location really doesn't have to be that fine, so the last known location is good enough. Thanks for the help. LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE); String providers[] = {"gps", "network", "passive"}; Location loc = null; for(String x : providers) { loc = lm.getLastKnownLocation(x); if(loc != null) break; } if(loc != null) { // do something, never reached }

    Read the article

  • Imagick: gifs, and background color

    - by TheButch3r
    Hi, I have 2 questions about using the php imagick class that I can't get working properly... 1.) I tried resizing / cropping a gif, and treated it as a normal image. It seemed to work, except that a few frames in the middle of the animation contained a small patch of artifacts. Is there a setting that should be used when working with multi-frame gifs? 2.) Is there a simple command to resize images if they are too small by just adding a background? For instance, if an image is 10x10, could I add a white background, and have a 100x100px image with the original in the upper left corner? Thanks for any help!

    Read the article

  • linux's fork and system resources

    - by Dmitry Bespalov
    Suppose I have following code in linux: int main() { FILE* f = fopen("file.txt", "w"); fork(); fwrite("A", 1, 1, f); fclose(f); return 0; } What I know about fork from documentation, is that it makes the copy of current process. It copies state of the memory as well, so *f should be equal in both instances. But what happens with system resources, such as a file handle? In this example I open the file with write intentions, so only one instance can write into file, right? Which of the instances will actually write into file? Who should care further about the file handle, and call fclose() ?

    Read the article

  • What is the easiest way to send a Javascript array via JSON to PHP?

    - by dscher
    I have a few arrays that I want to send to process with PHP. Using json2.js I will stringify the arrays like so: var JSONlinks = JSON.stringify(link_array); var JSONnotes = JSON.stringify(note_array); but then I'm confused. Do I need to use a XMLHttpRequest object? Is there another way? If that is the simplest way, could someone please just share the most basic instance of the code needed in order to send to PHP where I can then use JSON decode? I think it might help others in the future really. I'm currently using Jquery and I know there are many options out there for frameworks and each one may or may not make this process any easier. If you're using a framework in your reply please mention why you'd choose that framework rather than just javascript.

    Read the article

  • Objective-C: when does an assigned object get deallocated

    - by Stefan Klumpp
    If I have a instance method and within this method I do something like this: NSString *peopleString = [peopleList componentsJoinedByString: @", "]; ... UILabel *likeLabel = [[UILabel alloc] initWithFrame:CGRectMake(16.0+6.0f, 4.0f, 252.0f, 12.0f)]; [likeLabel setText:peopleString]; [likeLabel setFont:[UIFont fontWithName:@"Arial" size:12]]; [likeRow addSubview:likeLabel]; [likeLabel release]; The componentsJoinedByString doesn't contain a new, copy or alloc, thus I don't have to release it. What I'm wondering though is, when my peopleString gets deallocated. Might it happen to early? Meaning, before I can set the text in my label. Should I better use a [[NSString alloc] initWithString:[peopleList componentsJoinedByString: @", "]]; and release it at the end of this method?

    Read the article

  • NSMutableSet addObject question

    - by Jacob Relkin
    I've got a class that wraps around an NSMutableSet object, and I have an instance method that adds objects (using the addObject: method) to the NSMutableSet. This works well, but I'm smelling a performance hitch because inside the method i'm explicitly calling containsObject: before adding the object to the set. Three part question: Do I need to be calling containsObject: before I add an object to the set? If so, then what actual method should I be using, containsObject or containsObjectIdenticalTo:? If that is not so, what contains method gets invoked under the hood of addObject:? This is important to me because if I pass an object to containsObject: it would return true, but if I pass it to containsObjectIdenticalTo: it would return false.

    Read the article

  • New to javascript, why is jQuery such a beast?

    - by gnucom
    Hey Everyone, I'm new to javascript (functional programming is okay for me, though) and I am wondering how jQuery got away with some of the design decisions they made. Is it just too much work to fix now or what? For instance, there seems use of strange symbols in strings when accessing elements in the DOM or weird function definitions for $, that are forcing me to check references every other time I want to get some basic data. Can someone point me to a learning source where I can learn all of these nuances of jQuery (jQuery's examples just don't cut it, they're too spread out)? Maybe someone has a super good reference site/pdf for jQuery? Thanks

    Read the article

  • is i need to create UINavigationController for each Tabbar?

    - by RAGOpoR
    i have a problem is i got UItabbarController it contain 3 Tabbars each tabbar need to create own UINavigationController for them? in IB it can only link UINavigationController to 1 navigationcontroller of tabbar only. it can't multiple link. how can i resolve for it. i want to hide and unhide my toolbar. i think it it a bad idea if i must create 3 uinavigationcontroller instance variable for each tabbar. how can i reslove this issue?

    Read the article

  • Why are gettimeofday() intervals occasionally negative?

    - by Andres Jaan Tack
    I have an experimental library whose performance I'm trying to measure. To do this, I've written the following: struct timeval begin; gettimeofday(&begin, NULL); { // Experiment! } struct timeval end; gettimeofday(&end, NULL); // Print the time it took! std::cout << "Time: " << 100000 * (end.tv_sec - begin.tv_sec) + (end.tv_usec - begin.tv_usec) << std::endl; Occasionally, my results include negative timings, some of which are nonsensical. For instance: Time: 226762 Time: 220222 Time: 210883 Time: -688976 What's going on?

    Read the article

  • How can I maximally partition a set?

    - by Gregory Higley
    I'm trying to solve one of the Project Euler problems. As a consequence, I need an algorithm that will help me find all possible partitions of a set, in any order. For instance, given the set 2 3 3 5: 2 | 3 3 5 2 | 3 | 3 5 2 | 3 3 | 5 2 | 3 | 3 | 5 2 5 | 3 3 and so on. Pretty much every possible combination of the members of the set. I've searched the net of course, but haven't found much that's directly useful to me, since I speak programmer-ese not advanced-math-ese. Can anyone help me out with this? I can read pretty much any programming language, from BASIC to Haskell, so post in whatever language you wish.

    Read the article

  • Spring security and Struts 2

    - by Thanksforfish
    I have a struts2 action with an @Secured({"ROLE_ADMIN"}) to secure the execute method. In the execute method i assign a message to a member variable of the action, then return SUCCESS and end up on the jsp page. On the page I retrieve the actions member variable with <sroperty. private String greeting; public String execute() throws Exception { this.greeting="Hello"; return SUCCESS; } // getters and setters for greeting ... <s:property value="greeting" /> The problem is when the secured annotation is present the jsp shows nothing for the member variable but when @Secured is removed the whole thing behaves properly and shows the message that was set into the member variable. It appears that the actual security is working ok but when enabled via the annotation the member variable (or maybe the instance of the action) is not making its way onto the value stack. I cant see any error messages.

    Read the article

  • Why can't I access a web app running on my Mac via my iPhone?

    - by bpapa
    I'm developing an iPhone app that has a network component. I'm developing the app in Java (Google App Engine actually), running on port 8080. And it works, when I test my app in the iPhone simulator. But now I am trying to test on the device, and I can't hit my Jetty instance. I can certainly access my Mac via the iPhone because I'm able to hit http://10.0.1.7/~brianpapa/ and view my Home Folder when Web Sharing is turned on. But when I try to hit http://10.0.1.7:8080/, it says it can't connect to the server. Interestingly, if I try to hit http://10.0.1.7:8080/ from my mac, it doesn't work either - I have to use localhost as the hostname instead, then it's fine. Has anybody ever encountered this before, and know how to fix it?

    Read the article

  • Algorithm to classify a list of products?

    - by Martin
    I have a list representing products which are more or less the same. For instance, in the list below, they are all Seagate hard drives. Seagate Hard Drive 500Go Seagate Hard Drive 120Go for laptop Seagate Barracuda 7200.12 ST3500418AS 500GB 7200 RPM SATA 3.0Gb/s Hard Drive New and shinny 500Go hard drive from Seagate Seagate Barracuda 7200.12 Seagate FreeAgent Desk 500GB External Hard Drive Silver 7200RPM USB2.0 Retail For a human being, the hard drives 3 and 5 are the same. We could go a little bit further and suppose that the products 1, 3, 4 and 5 are the same and put in other categories the product 2 and 6. We have a huge list of products that I would like to classify. Does anybody have an idea of what would be the best algorithm to do such thing. Any suggestions? I though of a Bayesian classifier but I am not sure if it is the best choice. Any help would be appreciated! Thanks.

    Read the article

  • How to pay your users? (alternatives to PayPal)

    - by Sosh
    Hi, I would like to know what best non-paypal options are for paying users of your website (for services rendered for instance). How are others doing this at the moment? If you could mention specific services providers that would be most useful. This would have to work internationally, not be limited to one country. Thank you Update (in response to comments) Reason for excluding PayPal: I've had bad experiences with them in the past. Amounts: Well, i don't mean micropayments of a few cents, but could be anything from 40EUR - 500 EUR. Currency: I didn't mention this, but I would be paying in Euros.

    Read the article

  • A column ID occurred more than once in the specification

    - by Puzzle84
    Recently i've picked up my EF 4.1 / MVC 3 project again and started building in actual frontend capabilities. Now i'm developing a "simple" message system but upon going to that page i get the error as stated in the title EDIT It creates the database just not the models. Stack trace: [NullReferenceException: Object reference not set to an instance of an object.] ASP._Page_Views_Inbox_Index_cshtml.Execute() in c:\Development\MVC\DOCCL\Views\Inbox\Index.cshtml:18 System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +197 System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +81 System.Web.WebPages.StartPage.RunPage() +17 System.Web.WebPages.StartPage.ExecutePageHierarchy() +62 System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +76 System.Web.Mvc.RazorView.RenderView(ViewContext viewContext, TextWriter writer, Object instance) +222 System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext, TextWriter writer) +115 System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) +295 System.Web.Mvc.ControllerActionInvoker.InvokeActionResult(ControllerContext controllerContext, ActionResult actionResult) +13 System.Web.Mvc.<c_DisplayClass1c.b_19() +23 System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func1 continuation) +242 System.Web.Mvc.<>c__DisplayClass1e.<InvokeActionResultWithFilters>b__1b() +21 System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList1 filters, ActionResult actionResult) +177 System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +324 System.Web.Mvc.Controller.ExecuteCore() +106 System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +91 System.Web.Mvc.ControllerBase.System.Web.Mvc.IController.Execute(RequestContext requestContext) +10 System.Web.Mvc.<c_DisplayClassb.b_5() +34 System.Web.Mvc.Async.<c_DisplayClass1.b_0() +19 System.Web.Mvc.Async.<c_DisplayClass81.<BeginSynchronous>b__7(IAsyncResult _) +10 System.Web.Mvc.Async.WrappedAsyncResult1.End() +62 System.Web.Mvc.<c_DisplayClasse.b_d() +48 System.Web.Mvc.SecurityUtil.b_0(Action f) +7 System.Web.Mvc.SecurityUtil.ProcessInApplicationTrust(Action action) +22 System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +60 System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9 System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9478661 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +178 InnerException : {"A column ID occurred more than once in the specification."} The recently added code is. Controller: // // GET: /Inbox/Index/5/1 public ActionResult Index(int? Id, int Page = 1) { try { const int pageSize = 10; var messages = from m in horseTracker.Messages where m.ReceiverId.Equals(Id) select m; var paginatedMessages = new PaginatedList<Message>(messages, Page, pageSize); return View(paginatedMessages); } catch (Exception ex) { } return View(); } Models public class Message { [Key] public int Id { get; set; } [Required(ErrorMessage = "Subject is required")] [Display(Name = "Subject")] public string Subject { get; set; } [Required(ErrorMessage = "Message is required")] [Display(Name = "Message")] public string Content { get; set; } [Required] [Display(Name = "Date")] public DateTime Created { get; set; } public Boolean Read { get; set; } [Required(ErrorMessage = "Can't create a message without a user")] public int SenderId { get; set; } public virtual User Sender { get; set; } [Required(ErrorMessage = "Please pick a recipient")] public int ReceiverId { get; set; } public virtual User Receiver { get; set; } } public class User { [Key] public int Id { get; set; } [Required] [Display(Name = "Username")] public string UserName { get; set; } [Required] [Display(Name = "First Name")] public string FirstName { get; set; } [Required] [Display(Name = "Last Name")] public string LastName { get; set; } [Required] [Display(Name = "E-Mail")] public string Email { get; set; } [Required] [Display(Name = "Password")] public string Password { get; set; } [Required] [Display(Name = "Country")] public string Country { get; set; } public string EMail { get; set; } //Races public virtual ICollection<Message> Messages { get; set; } } modelBuilder.Entity<User>() .HasMany(u => u.Messages) .WithRequired(m => m.Receiver) .HasForeignKey(m => m.ReceiverId) .WillCascadeOnDelete(false); Anyone have a clue on why i might be getting that error? Before i added these classes it was working fine.

    Read the article

  • InnoDB not supported by webhost. What now?

    - by Peter Perhác
    I was developing a small WAMP web application on my laptop, where I have an instance of mySQL running and I chose InnoDB for my DB engine. After several weeks' development I wanted to make it available to the public and found out the database server provided by my web host does not support InnoDB, only MyISAM. The create-and-populate script generated from the innoDB schema on my laptop, when executed against the live database, can manage to create individual TABLES but then runs into problems creating the VIEWs. Are views not supported in MyISAM? I know FOREIGN KEYs are not. That's very much why I made the choice of InnoDB... What are my chances of making my innoDB schema design work with myISAM? Is there any straightforward way of converting the whole schema from one storage engine to the other? Should I look for another web host that does provide a mysql db that supports innoDB?

    Read the article

  • Locking a file to verify a single execution of a service. How reliable?

    - by Camilo Díaz
    Hello, I am deploying a little service to an UNIX(AIX) system. I want to check if there is no active instance of that service running when starting it. How reliable is to implement that check like this? Try to acquire a lock on a file (w/ FileChannel) If succeeds, keep lock and continue execution If fails, exit and refuse to run the main body I am aware of software like the Tanuki wrapper, however, I'm longing for a simpler(maybe not portable) solution. Regarding PIDFILE(s): I want to avoid using them if possible, as I don't have administrative rights on the machine, neither knowledge in AIX's shell programming.

    Read the article

  • how to order a group result with Linq?

    - by Aaron
    How can I order the results from "group ... by... into..." statement in linq? For instance: var queryResult = from records in container.tableWhatever where records.Time >= DateTime.Today group records by tableWhatever.tableHeader.UserId into userRecords select new { UserID = userRecords.Key, Records = userRecords }; The query returns records in table "contain.tableWhatever" grouped by "UserId". I want the returned results within each group ordered by time decending. How can I do that? More specific, assume the above query return only one group like the following: {UserID = 1, Records= {name1 5/3/2010_7:10pm; name2 5/3/2010_8:10pm; name3 5/3/2010_9:10pm} } After insert the orderby statement in the above query, the returned results should be like this: {UserID = 1, Records= {name3 5/3/2010_9:10pm; name2 5/3/2010_8:10pm; name1 5/3/2010_7:10pm} } Thanks for help!

    Read the article

  • WxPython multiple grid instances

    - by randomPythonHacker
    Does anybody know how I can get multiple instances of the same grid to display on one frame? Whenever I create more than 1 instance of the same object, the display of the original grid widget completely collapses and I'm left unable to do anything with it. For reference, here's the code: import wx import wx.grid as gridlib class levelGrid(gridlib.Grid): def __init__(self, parent, rows, columns): gridlib.Grid.__init__(self, parent, -1) self.moveTo = None self.CreateGrid(rows, columns) self.SetDefaultColSize(32) self.SetDefaultRowSize(32) self.SetColLabelSize(0) self.SetRowLabelSize(0) self.SetDefaultCellBackgroundColour(wx.BLACK) self.EnableDragGridSize(False) class mainFrame(wx.Frame): def __init__(self, parent, id, title): wx.Frame.__init__(self, parent, id, title, size=(768, 576)) editor = levelGrid(self, 25, 25) panel1 = wx.Panel(editor, -1) #vbox = wx.BoxSizer(wx.VERTICAL) #vbox.Add(editor, 1, wx.EXPAND | wx.ALL, 5) #selector = levelGrid(self, 1, 25) #vbox.Add(selector, 1, wx.EXPAND |wx.BOTTOM, 5) self.Centre() self.Show(True) app = wx.App() mainFrame(None, -1, "SLAE") app.MainLoop()

    Read the article

  • Excel can't remember how to copy/paste

    - by wootscootinboogie
    So, maybe someone else has an idea why this happens. I have a full-fledged version of Office 2007, works fine and all that jazz. However, if I try to copy and paste query results from SSMS, or anywhere else for that matter, I have to have an instance of Excel open and then paste. I can't copy, open Excel, and then paste. The little 'wait' circle pops up for a split second but nothing is pasted. I have never ran across this with any other program. Any good explanation for this? FFIW, it's Excel 2007 running in compatibility mode.

    Read the article

  • Where to draw the line between efficiency and practicality

    - by dclowd9901
    I understand very well the need for websites' front ends to be coded and compressed as much as possible, however, I feel like I have more lax standards than others when it comes to practical applications. For instance, while I understand why some would, I don't see anything wrong with putting selectors in the <html> or <body> tags on a website with an expected small visitation rate. I would only do this for a cheap website for a small client, because I can't really justify the cost of time otherwise. So, that said, do you think it's okay to draw a line? Where do you draw yours?

    Read the article

  • Overriding the admin Media class

    - by shacker
    Given an admin media class that sets up a rich text editor, like: class TutorialAdmin(admin.ModelAdmin): fields... class Media: js = ['/paths/to/tinymce.js',] I would like the ability to selectively override js depending on a field value in the model it references. I've added a "use_editor" boolean to the Tutorial model. The question is, how can I detect whether the current instance has that bool set? I'd like to end up with something like: class Media: if self.use_editor: js = ['/path/to/tinymce.js',] else: js = '' Ideas? Thanks.

    Read the article

  • read java.security.key stored as object inside a file which is in jar

    - by Tal
    I saved a PublicKey instance in a file using ObjectOutputStream. This file is then stored inside a jar file which is then loaded by JBoss. I'm trying to read this file but it throws me an exception telling that it's not serializable. Here is the code : InputStream input = KeyLoader.class.getClassLoader().getResourceAsStream(resource); ObjectInputStream objectInputStream = new ObjectInputStream(input); Object obj = objectInputStream.readObject(); Key output = (Key) obj; objectInputStream.close(); return output; which throws me this exception An exception occurred: java.io.NotSerializableException

    Read the article

< Previous Page | 342 343 344 345 346 347 348 349 350 351 352 353  | Next Page >