Search Results

Search found 13227 results on 530 pages for 'memory efficiency'.

Page 461/530 | < Previous Page | 457 458 459 460 461 462 463 464 465 466 467 468  | Next Page >

• How to append new elements to Xml from a stream

  - by Wololo

  I have a method which returns some xml in a memory stream private MemoryStream GetXml() { XmlWriterSettings settings = new XmlWriterSettings(); settings.Indent = true; using (MemoryStream memoryStream = new MemoryStream()) { using (XmlWriter writer = XmlWriter.Create(memoryStream, settings)) { writer.WriteStartDocument(); writer.WriteStartElement("root"); writer.WriteStartElement("element"); writer.WriteString("content"); writer.WriteEndElement(); writer.WriteEndElement(); writer.WriteEndDocument(); writer.Flush(); } return memoryStream; } } In this example the format of the xml will be: <?xml version="1.0" encoding="utf-8"?> <root> <element>content</element> </root> How can i insert a new element under the root e.g <?xml version="1.0" encoding="utf-8"?> <root> <element>content</element> ----->New element here <------ </root> EDIT: Also please suggest the most efficient method as returning a memorystream may not be the best solution. The final xml will be passed to a custom HttpHandler so what are the best options for writing the output? context.Response.Write vs context.Response.OutputStream

  Read the article

• Behavior of retained propertie while holder is retained

  - by Aurélien Vallée

  Hello everyone, I am a beginner ObjectiveC programmer, coming from the C++ world. I find it very difficult to understand the memory management offered by NSObject :/ Say I have the following class: @interface User : NSObject { NSString* name; } @property (nonatomic,retain) NSString* name; - (id) initWithName: (NSString*) theName; - (void) release; @end @implementation User @synthetise name - (id) initWithName: (NSString*) theName { if ( self = [super init] ) { [self setName:theName]; } return self; } - (void) release { [name release]; [super release]; } @end No considering the following code, I can't understand the retain count results: NSString* name = [[NSString alloc] initWithCString:/*C string from sqlite3*/]; // (1) name retainCount = 1 User* user = [[User alloc] initWithName:name]; // (2) name retainCount = 2 [whateverMutableArray addObject:user]; // (3) name retainCount = 2 [user release]; // (4) name retainCount = 1 [name release]; // (5) name retainCount = 0 At (4), the retain count of name decreased from 2 to 1. But that's not correct, there is still the instance of user inside the array that points to name ! The retain count of a variable should only decrease when the retain count of a referring variable is 0, that is, when it is dealloced, not released.

  Read the article

• hudson.util.ProcessTreeTest test error

  - by senzacionale

  error: Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.011 sec Running hudson.util.ProcessTreeTest Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0.181 sec <<< FAILURE! Running hudson.model.LoadStatisticsTest Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 2.089 sec Running hudson.util.ArgumentListBuilderTest Tests run: 5, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.053 sec Running hudson.util.RobustReflectionConverterTest Tests run: 2, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.029 sec Running hudson.util.VersionNumberTest Tests run: 3, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.074 sec Running hudson.util.CyclicGraphDetectorTest Tests run: 3, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.038 sec Results : Tests in error: testRemoting(hudson.util.ProcessTreeTest) Tests run: 102, Failures: 0, Errors: 1, Skipped: 0 [INFO] ------------------------------------------------------------------------ [ERROR] BUILD FAILURE [INFO] ------------------------------------------------------------------------ [INFO] There are test failures. Please refer to D:\PROJEKTI\Maven\hudson\main\core\target\surefire-reports for the individual test results. [INFO] ------------------------------------------------------------------------ [INFO] For more information, run Maven with the -e switch [INFO] ------------------------------------------------------------------------ [INFO] Total time: 17 minutes 58 seconds [INFO] Finished at: Fri Jun 11 21:04:46 CEST 2010 [INFO] Final Memory: 85M/152M [INFO] ------------------------------------------------------------------------ error log: ------------------------------------------------------------------------------- Test set: hudson.util.ProcessTreeTest ------------------------------------------------------------------------------- Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0.181 sec <<< FAILURE! testRemoting(hudson.util.ProcessTreeTest) Time elapsed: 0.169 sec <<< ERROR! org.jvnet.winp.WinpException: Failed to read environment variable table error=299 at .\envvar-cmdline.cpp:114 at org.jvnet.winp.Native.getCmdLineAndEnvVars(Native Method) at org.jvnet.winp.WinProcess.parseCmdLineAndEnvVars(WinProcess.java:114) at org.jvnet.winp.WinProcess.getEnvironmentVariables(WinProcess.java:109) at hudson.util.ProcessTree$Windows$1.getEnvironmentVariables(ProcessTree.java:419) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at hudson.remoting.RemoteInvocationHandler$RPCRequest.perform(RemoteInvocationHandler.java:274) at hudson.remoting.RemoteInvocationHandler$RPCRequest.call(RemoteInvocationHandler.java:255) at hudson.remoting.RemoteInvocationHandler$RPCRequest.call(RemoteInvocationHandler.java:215) at hudson.remoting.UserRequest.perform(UserRequest.java:114) at hudson.remoting.UserRequest.perform(UserRequest.java:48) at hudson.remoting.Request$2.run(Request.java:270) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:619) does anyone have any idea what can be wrong in test? Regards

  Read the article

• What's the largest (most complex) PHP algorithm ever implemented in a single monolithic PHP script?

  - by Alex R

  I'm working on a tool which converts PHP code to Scala. As one of the finishing touches, I'm in need of a really good (er, somewhat biased) benchmark. By dumb luck my first benchmark attempt was with some code which uses bcmath extensively, which unfortunately is 1000x slower in Java, making the Scala code 22x slower overall than the original PHP. So I'm looking for some meaningful PHP benchmark with the following characteristics: The source needs to be in a single file. I need it to be simple to setup - no databases, hard-to-find input files, etc. Simple text input and output preferred. It should not use features that are slow in Java (BigInteger, trigonometric functions, etc). It should not use exoteric or dynamic PHP functions (e.g. no "eval" or "variable vars"). It should not over-rely on built-in libraries, e.g. MD5, crypt, etc. It should not be I/O bound. A CPU-bound memory-hungry algorithm is preferred. Basically, intensive OO operations, integer and string manipulation, recursion, etc would be great. Thanks

  Read the article

• priority queue with limited space: looking for a good algorithm

  - by SigTerm

  This is not a homework. I'm using a small "priority queue" (implemented as array at the moment) for storing last N items with smallest value. This is a bit slow - O(N) item insertion time. Current implementation keeps track of largest item in array and discards any items that wouldn't fit into array, but I still would like to reduce number of operations further. looking for a priority queue algorithm that matches following requirements: queue can be implemented as array, which has fixed size and _cannot_ grow. Dynamic memory allocation during any queue operation is strictly forbidden. Anything that doesn't fit into array is discarded, but queue keeps all smallest elements ever encountered. O(log(N)) insertion time (i.e. adding element into queue should take up to O(log(N))). (optional) O(1) access for *largest* item in queue (queue stores *smallest* items, so the largest item will be discarded first and I'll need them to reduce number of operations) Easy to implement/understand. Ideally - something similar to binary search - once you understand it, you remember it forever. Elements need not to be sorted in any way. I just need to keep N smallest value ever encountered. When I'll need them, I'll access all of them at once. So technically it doesn't have to be a queue, I just need N last smallest values to be stored. I initially thought about using binary heaps (they can be easily implemented via arrays), but apparently they don't behave well when array can't grow anymore. Linked lists and arrays will require extra time for moving things around. stl priority queue grows and uses dynamic allocation (I may be wrong about it, though). So, any other ideas?

  Read the article

• PHP readfile() and large downloads

  - by Nirmal

  While setting up an online file management system, and now I have hit a block. I am trying to push the file to the client using this modified version of readfile: function readfile_chunked($filename,$retbytes=true) { $chunksize = 1*(1024*1024); // how many bytes per chunk $buffer = ''; $cnt =0; // $handle = fopen($filename, 'rb'); $handle = fopen($filename, 'rb'); if ($handle === false) { return false; } while (!feof($handle)) { $buffer = fread($handle, $chunksize); echo $buffer; ob_flush(); flush(); if ($retbytes) { $cnt += strlen($buffer); } } $status = fclose($handle); if ($retbytes && $status) { return $cnt; // return num. bytes delivered like readfile() does. } return $status; } But when I try to download a 13 MB file, it's just breaking at 4 MB. What would be the issue here? It's definitely not the time limit of any kind because I am working on a local network and speed is not an issue. The memory limit in PHP is set to 300 MB. Thank you for any help.

  Read the article

• C#/Java: Proper Implementation of CompareTo when Equals tests reference identity

  - by Paul A Jungwirth

  I believe this question applies equally well to C# as to Java, because both require that {c,C}ompareTo be consistent with {e,E}quals: Suppose I want my equals() method to be the same as a reference check, i.e.: public bool equals(Object o) { return this == o; } In that case, how do I implement compareTo(Object o) (or its generic equivalent)? Part of it is easy, but I'm not sure about the other part: public int compareTo(Object o) { if (! (o instanceof MyClass)) return false; MyClass other = (MyClass)o; if (this == other) { return 0; } else { int c = foo.CompareTo(other.foo) if (c == 0) { // what here? } else { return c; } } } I can't just blindly return 1 or -1, because the solution should adhere to the normal requirements of compareTo. I can check all the instance fields, but if they are all equal, I'd still like compareTo to return a value other than 0. It should be true that a.compareTo(b) == -(b.compareTo(a)), and the ordering should stay consistent as long as the objects' state doesn't change. I don't care about ordering across invocations of the virtual machine, however. This makes me think that I could use something like memory address, if I could get at it. Then again, maybe that won't work, because the Garbage Collector could decide to move my objects around. hashCode is another idea, but I'd like something that will be always unique, not just mostly unique. Any ideas?

  Read the article

• wsdl2 java :Java heap space

  - by PiNY

  Hi! I'm working with web services. I have a file wdsl and I trasnformed it in two java files: wsdl2java -uri nameFile.wsdl One of the java file created has 87kb. When I try it to open with eclipse I have this error: java.lang.OutOfMemoryError: Java heap space at java.util.Arrays.copyOf(Unknown Source) at java.lang.AbstractStringBuilder.expandCapacity(Unknown Source) at java.lang.AbstractStringBuilder.append(Unknown Source) at java.lang.StringBuffer.append(Unknown Source) at org.eclipse.core.internal.filebuffers.FileStoreTextFileBuffer.setDocumentContent(FileStoreTextFileBuffer.java:586) at org.eclipse.core.internal.filebuffers.FileStoreTextFileBuffer.initializeFileBufferContent(FileStoreTextFileBuffer.java:352) at org.eclipse.core.internal.filebuffers.FileStoreFileBuffer.create(FileStoreFileBuffer.java:63) at org.eclipse.core.internal.filebuffers.TextFileBufferManager.connectFileStore(TextFileBufferManager.java:150) at org.eclipse.ui.editors.text.TextFileDocumentProvider.createFileInfo(TextFileDocumentProvider.java:567) at org.eclipse.jdt.internal.ui.javaeditor.CompilationUnitDocumentProvider.createFileInfo(CompilationUnitDocumentProvider.java:969) at org.eclipse.ui.editors.text.TextFileDocumentProvider.connect(TextFileDocumentProvider.java:478) at org.eclipse.jdt.internal.ui.javaeditor.CompilationUnitDocumentProvider.connect(CompilationUnitDocumentProvider.java:1229) at org.eclipse.ui.texteditor.AbstractTextEditor.doSetInput(AbstractTextEditor.java:4056) at org.eclipse.ui.texteditor.StatusTextEditor.doSetInput(StatusTextEditor.java:217) at org.eclipse.ui.texteditor.AbstractDecoratedTextEditor.doSetInput(AbstractDecoratedTextEditor.java:1444) at org.eclipse.jdt.internal.ui.javaeditor.JavaEditor.internalDoSetInput(JavaEditor.java:2578) at org.eclipse.jdt.internal.ui.javaeditor.JavaEditor.doSetInput(JavaEditor.java:2551) at org.eclipse.jdt.internal.ui.javaeditor.CompilationUnitEditor.doSetInput(CompilationUnitEditor.java:1371) at org.eclipse.ui.texteditor.AbstractTextEditor$19.run(AbstractTextEditor.java:3043) at org.eclipse.jface.operation.ModalContext.runInCurrentThread(ModalContext.java:464) at org.eclipse.jface.operation.ModalContext.run(ModalContext.java:372) at org.eclipse.jface.window.ApplicationWindow$1.run(ApplicationWindow.java:759) at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70) at org.eclipse.jface.window.ApplicationWindow.run(ApplicationWindow.java:756) at org.eclipse.ui.internal.WorkbenchWindow.run(WorkbenchWindow.java:2600) at org.eclipse.ui.texteditor.AbstractTextEditor.internalInit(AbstractTextEditor.java:3061) at org.eclipse.ui.texteditor.AbstractTextEditor.init(AbstractTextEditor.java:3088) at org.eclipse.ui.internal.EditorManager.createSite(EditorManager.java:798) at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:647) at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:465) at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:595) at org.eclipse.ui.internal.EditorReference.getEditor(EditorReference.java:289) I want to now if : 1) It problem to the arguments wsdl2java . It means some way to create more java files intead of the big one. 2) Memory problem eclipse How can I resolve it? Thanks

  Read the article

• asp.net, how to change text color to red in child nodes in VB codes?

  - by StudentIT

  I got everything worked now by list of server Name but I want to add a IF statement by checking a column from SQL Server called Compliance by either True or False value listed. If it False, the Name will change text color to Red. If it True, the Name won't change text color. I am not sure how add that in VB codes side. I am pretty sure that I would need to put IF statement inside While dr.Read(). I am pretty new to VB.Net and not sure which VB code that change text color. Here is my VB codes, Sub loadData() 'clear treeview control TreeViewGroups.Nodes.Clear() 'fetch owner data and save to in memory table Dim sqlConn As New System.Data.SqlClient.SqlConnection((ConfigurationManager.ConnectionStrings("SOCT").ConnectionString)) Dim strSqlSecondary As String = "SELECT [Name] FROM [dbo].[ServerOwners] where SecondaryOwner like @uid order by [name]" 'Getting a list of True or False from Compliance column Dim strSqlCompliance As String = "SELECT [Compliance] FROM [dbo].[ServerOwners] where SecondaryOwner like @uid order by [name]" Dim cmdSecondary As New System.Data.SqlClient.SqlCommand(strSqlSecondary, sqlConn) Dim cmdCompliance As New System.Data.SqlClient.SqlCommand(strSqlCompliance, sqlConn) cmdSecondary.Parameters.AddWithValue("@uid", TNN.NEAt.GetUserID()) cmdCompliance.Parameters.AddWithValue("@uid", TNN.NEAt.GetUserID()) Dim dr As System.Data.SqlClient.SqlDataReader Try sqlConn.Open() Dim root As TreeNode Dim rootNode As TreeNode Dim firstNode As Integer = 0 'Load Primary Owner Node 'Create RootTreeNode dr = cmdSecondary.ExecuteReader() If dr.HasRows Then 'Load Secondary Owner Node 'Create RootTreeNode root = New TreeNode("Secondary Owner", "Secondary Owner") TreeViewGroups.Nodes.Add(root) root.SelectAction = TreeNodeSelectAction.None rootNode = TreeViewGroups.Nodes(firstNode) 'populate the child nodes While dr.Read() Dim child As TreeNode = New TreeNode(dr("Name"), dr("Name")) rootNode.ChildNodes.Add(child) child.SelectAction = TreeNodeSelectAction.None End While dr.Close() cmdSecondary.Dispose() End If 'check if treeview has nodes If TreeViewGroups.Nodes.Count = 0 Then noServers() End If Catch ex As Exception hide() PanelError.Visible = True LabelError.Text = ex.ToString() Finally sqlConn.Dispose() End Try End Sub

  Read the article

• What would be the safest way to store objects of classes derived from a common interface in a common

  - by Svenstaro

  I'd like to manage a bunch of objects of classes derived from a shared interface class in a common container. To illustrate the problem, let's say I'm building a game which will contain different actors. Let's call the interface IActor and derive Enemy and Civilian from it. Now, the idea is to have my game main loop be able to do this: // somewhere during init std::vector<IActor> ActorList; Enemy EvilGuy; Civilian CoolGuy; ActorList.push_back(EvilGuy); ActorList.push_back(CoolGuy); and // main loop while(!done) { BOOST_FOREACH(IActor CurrentActor, ActorList) { CurrentActor.Update(); CurrentActor.Draw(); } } ... or something along those lines. This example obviously won't work but that is pretty much the reason I'm asking here. I'd like to know: What would be the best, safest, highest-level way to manage those objects in a common heterogeneous container? I know about a variety of approaches (Boost::Any, void*, handler class with boost::shared_ptr, Boost.Pointer Container, dynamic_cast) but I can't decide which would be the way to go here. Also I'd like to emphasize that I want to stay away as far as possible from manual memory management or nested pointers. Help much appreciated :).

  Read the article

• How to get the "real" colors when exporting a GDI drawing to bmp

  - by Rodrigo

  Hi guys I'm developing a ASP.Net web handler that returns images making a in-memory System.Windows.Forms.Control and then exports the rendered control as a bitmap compressed to PNG, using the method DrawToBitmap(). The classes are fully working by now, except for a problem with the color assignment. By example, this is a Gauge generated by the web handler. The colors assigned to the inner parts of the gauge are red (#FF0000), yellow (#FFFF00) and green (#00FF00) but I only get a dully version of each color (#CB100F for red, #CCB70D for yellow and #04D50D for green). The background is a bmp file containing the color gradient. The color loss happens whether the background is a gradient as the sample, a black canvas, a white canvas, a transparent canvas, even when there is not a background set. With black background With transparent background With a white background Without a background set With pixel format in Format32bppArgb I've tried multiple bitmap color deeps, output formats, compression level, etc. but none of them seems to work. Any ideas? This is a excerpt of the source code: Bitmap bmp = new Bitmap(w, h, System.Drawing.Imaging.PixelFormat.Format32bppPArgb); Image bgimage = (Image) HttpContext.GetGlobalResourceObject("GraphicResources", "GaugeBackgroundImage"); Canvas control_canvas = new Canvas(); .... //the routine that makes the gauge .... control_canvas.DrawToBitmap(bmp, new Rectangle(0, 0, w, h));

  Read the article

• Django upload failing on request data read error

  - by Jake

  Hi All, I've got a Django app that accepts uploads from jQuery uploadify, a jQ plugin that uses flash to upload files and give a progress bar. Files under about 150k work, but bigger files always fail and almost always at around 192k (that's 3 chunks) completed, sometimes at around 160k. The Exception I get is below. exceptions.IOError request data read error File "/usr/lib/python2.4/site-packages/django/core/handlers/wsgi.py", line 171, in _get_post self._load_post_and_files() File "/usr/lib/python2.4/site-packages/django/core/handlers/wsgi.py", line 137, in _load_post_and_files self._post, self._files = self.parse_file_upload(self.META, self.environ[\'wsgi.input\']) File "/usr/lib/python2.4/site-packages/django/http/__init__.py", line 124, in parse_file_upload return parser.parse() File "/usr/lib/python2.4/site-packages/django/http/multipartparser.py", line 192, in parse for chunk in field_stream: File "/usr/lib/python2.4/site-packages/django/http/multipartparser.py", line 314, in next output = self._producer.next() File "/usr/lib/python2.4/site-packages/django/http/multipartparser.py", line 468, in next for bytes in stream: File "/usr/lib/python2.4/site-packages/django/http/multipartparser.py", line 314, in next output = self._producer.next() File "/usr/lib/python2.4/site-packages/django/http/multipartparser.py", line 375, in next data = self.flo.read(self.chunk_size) File "/usr/lib/python2.4/site-packages/django/http/multipartparser.py", line 405, in read return self._file.read(num_bytes) When running locally on the Django development server, big files work. I've tried setting my FILE_UPLOAD_HANDLERS = ("django.core.files.uploadhandler.TemporaryFileUploadHandler",) in case it was the memory upload handler, but it made no difference. Does anyone know how to fix this?

  Read the article

• How to estimate size of data to transfer when using DbCommand.ExecuteXXX?

  - by Yadyn

  I want to show the user detailed progress information when performing potentially lengthy database operations. Specifically, when inserting/updating data that may be on the order of hundreds of KB or MB. Currently, I'm using in-memory DataTables and DataRows which are then synced with the database via TableAdapter.Update calls. This works fine and dandy, but the single call leaves little opportunity to glean any kind of progress info to show to the user. I have no idea how much data is passing through the network to the remote DB or its progress. Basically, all I know is when Update returns and it is assumed complete (barring any errors or exceptions). But this means all I can show is 0% and then a pause and then 100%. I can count the number of rows, even going so far to cound how many are actually Modified or Added, and I could even maybe calculate per DataRow its estimated size based on the datatype of each column, using sizeof for value types like int and checking length for things like strings or byte arrays. With that, I could probably determine, before updating, an estimated total transfer size, but I'm still stuck without any progress info once Update is called on the TableAdapter. Am I stuck just using an indeterminate progress bar or mouse waiting cursor? Would I need to radically change our data access layer to be able to hook into this kind of information? Even if I can't get it down to the precise KB transferred (like a web browser file download progress bar), could I at least know when each DataRow/DataTable finishes or something? How do you best show this kind of progress info using ADO.NET?

  Read the article

• Problem with .Contains

  - by Rene

  Hello there, I have a little problem which i can't solve. I want to use an SQL-In-Statement in Linq. I've read in this Forum and in other Forums that I have to use the .Contains (with reverse-thinking-notation :-)). As input i have a List of Guids. I first copied them into an array and then did something like that : datatoget = (from p in objectContext.MyDataSet where ArrayToSearch.Contains(p.Subtable.Id.ToString()) select p).ToList(); datatoget is the result in which all records matching the Subtable.Id (which is a Guid) should be stored. Subtable is a Detail-Table from MyData, and the Id is a Guid-Type. I've tried several things (Convert Guid to String, and then using .Contains, etc), but I always get an Exception which says : 'Linq to Entities' doesn't recognize the Method 'Boolean Contains(System.Guid) and is not able to Translate this method into a memory expression. (Something like that, because I'm using the German Version of VS2008) I am using L2E with .NET 3.5 and am programming in C# with VS 2008. I've read several Examples, but it doesn't work. Is it perhaps because of using Guid's instead of strings ? I've also tried to write my own compare-function, but I don't know how to integrate it so that .NET calls my function for comparing.

  Read the article

• JConsole does not connect when a program (running in eclipse) is waiting for a console input

  - by Calm Storm

  Hi, I have a problem similar to the one mentioned here. I have a program which launches a selenium browser and refreshes it every 2 seconds. My idea here was to monitor the memory usage of my application as the page is being hit. This console program does a "System.in.read" and when a user presses enter key, this stops the browser refresh thread. I run the program and it runs as I would expect it to. But when I fire jconsole and attach it to the process, it looks like jconsole waits forever to attach. This is because of the "System.in.read", apparently as shown in the JConsole source. In my code it makes perfect sense for me to terminte the browser when user presses something so is there any alternative available at all ? (Posted code sample below) package com.ekanathk; import java.util.ArrayList; import java.util.List; import org.junit.Test; public class MultiThread { @Test public void testSimple() throws Exception { List<Integer> x = new ArrayList<Integer>(); for(int i = 0; i < 1000; i++) { x.add(i); } System.out.print("Press Enter to stop (try attach a jconsole now...."); System.in.read(); } } The problem here seems to be that any System.in.read (either in Main thread or any threads) seems to completely block jconsole. I guess the problem essentially boils down to multiple threads requesting system inputs at the same time? Is there a solution ? UPDATE 1: It seems this works fine when launching the class from a command line, however when I run from eclipse, jconsole cant connect. Any reasons ?

  Read the article

• How to implement Session timeout in Web Server Side?

  - by Morgan Cheng

  I beheld a web framework implementing in-memory session in this way. The session object is added to Cache with timeout. When the time is out, the session is removed from Cache automatically. To protect race condition, each request should acquire lock on given session object to proceed. Each request will "touch" the session in Cache to refresh the timeout. Everything looks fine, until this scenario is discovered. Say, one operation takes a long time, longer than timeout. Another request comes and wait on session lock which is currently hold by the long-time request. Finally, the long-time request is over, it releases the lock. But, since it already takes longer time than timeout, the session object is already removed from Cache. This is obvious because the only request holding the lock doesn't have a chance to "touch" the session object in cache. The second request gets the lock but cannot retrieve the expired Session object. Oops... To fix this issue, the second request has to re-create the Session object. But, this is just like digging a buried dead body from tomb and try to bring it back to life. It causes buggy code. I'm wondering what's the best way to implement timeout in session to handle such scenario. I know that current platform must have good session mechanism. I just want to know the under-the-hood how.

  Read the article

• Windows console

  - by b-gen-jack-o-neill

  Hello. Well, I have a simple question, at least I hope its simple. I was interested in win32 console for a while. Our teacher told us, that windows console is just for DOS and real mode emulation purposes. Well, I know it is not true, becouse DOS applications are runned by emulator which only uses console to display output. Another thing I learned is that console is built into Windows since NT. Well. But what I could not find is, how actually are console programs written to use console. I use Visual C++ for programming (well, for learning). So, the only thing I need to do for using console is select console project. I first thought that windows decides wheather it run app in console or tries to run app in window mode. So I created win32 program and tried printf(). Well, I could not compile it. I know that by definition printf() prints text or variables to stdout. I also found that stdout is the console interface for output. But, I could not find what actually stdout is. So, basicly what I want to ask is, where is the difference between console app and win32 app. I thought that windows starts console when it gets command from "console-family" functions. But obvisously it does not, so there must be some code that actually commands windows to create console interface. And the second question is, when the console is created, how does windows recognize which console terminal is used for what app? I mean, what actually is stdout? Is it a area in memory , or some windows routine that is called? Thanks.

  Read the article

• Best practices for Java logging from multiple threads?

  - by Jason S

  I want to have a diagnostic log that is produced by several tasks managing data. These tasks may be in multiple threads. Each task needs to write an element (possibly with subelements) to the log; get in and get out quickly. If this were a single-task situation I'd use XMLStreamWriter as it seems like the best match for simplicity/functionality without having to hold a ballooning XML document in memory. But it's not a single-task situation, and I'm not sure how to best make sure this is "threadsafe", where "threadsafe" in this application means that each log element should be written to the log correctly and serially (one after the other and not interleaved in any way). Any suggestions? I have a vague intuition that the way to go is to use a queue of log elements (with each one able to be produced quickly: my application is busy doing real work that's performance-sensitive), and have a separate thread which handles the log elements and sends them to a file so the logging doesn't interrupt the producers. The logging doesn't necessarily have to be XML, but I do want it to be structured and machine-readable. edit: I put "threadsafe" in quotes. Log4j seems to be the obvious choice (new to me but old to the community), why reinvent the wheel...

  Read the article

• How to cast sockaddr_storage and avoid breaking strict-aliasing rules

  - by sinoth

  I'm using Beej's Guide to Networking and came across an aliasing issue. He proposes a function to return either the IPv4 or IPv6 address of a particular struct: 1 void *get_in_addr( struct sockaddr *sa ) 2 { 3 if (sa->sa_family == AF_INET) 4 return &(((struct sockaddr_in*)sa)->sin_addr); 5 else 6 return &(((struct sockaddr_in6*)sa)->sin6_addr); 7 } This causes GCC to spit out a strict-aliasing error for sa on line 3. As I understand it, it is because I call this function like so: struct sockaddr_storage their_addr; ... inet_ntop(their_addr.ss_family, get_in_addr((struct sockaddr *)&their_addr), connection_name, sizeof connection_name); I'm guessing the aliasing has to do with the fact that the their_addr variable is of type sockaddr_storage and another pointer of a differing type points to the same memory. Is the best way to get around this sticking sockaddr_storage, sockaddr_in, and sockaddr_in6 into a union? It seems like this should be well worn territory in networking, I just can't find any good examples with best practices. Also, if anyone can explain exactly where the aliasing issue takes place, I'd much appreciate it.

  Read the article

• Tips on managing dependencies for a release?

  - by Andrew Murray

  Our system comprises many .NET websites, class libraries, and a MSSQL database. We use SVN for source control and TeamCity to automatically build to a Test server. Our team is normally working on 4 or 5 projects at a time. We try to lump many changes into a largish rollout every 2-4 weeks. My problem is with keeping track of all the dependencies for a rollout. Example: Website A cannot go live until we've rolled out Branch X of Class library B, built in turn against the Trunk of Class library C, which needs Config Updates Y and Z and Database Update D, which needs Migration Script E... It gets even more complex - like making sure each developer's project is actually compatible with the others and are building against the same versions. Yes, this is a management issue as much as a technical issue. Currently our non-optimal solution is: a whiteboard listing features that haven't gone live yet relying on our memory and intuition when planning the rollout, until we're pretty sure we've thought of everything... a dry-run on our Staging environment. It's a good indication but we're often not sure if Staging is 100% in sync with Live - part of the problem I'm hoping to solve. some amount of winging it on rollout day. So far so good, minus a few close calls. But as our system grows, I'd like a more scientific release management system allowing for more flexibility, like being able to roll out a single change or bugfix on it's own, safe in the knowledge that it won't break anything else. I'm guessing the best solution involves some sort of version numbering system, and perhaps using a project management tool. We're a start-up, so we're not too hot on religiously sticking to rigid processes, but we're happy to start, providing it doesn't add more overhead than it's worth. I'd love to hear advice from other teams who have solved this problem.

  Read the article

• should std::auto_ptr<>::operator = reset / deallocate its existing pointee ?

  - by afriza

  I read here about std::auto_ptr<::operator= Notice however that the left-hand side object is not automatically deallocated when it already points to some object. You can explicitly do this by calling member function reset before assigning it a new value. However, when I read the source code for header file C:\Program Files\Microsoft Visual Studio 8\VC\ce\include\memory template<class _Other> auto_ptr<_Ty>& operator=(auto_ptr<_Other>& _Right) _THROW0() { // assign compatible _Right (assume pointer) reset(_Right.release()); return (*this); } auto_ptr<_Ty>& operator=(auto_ptr<_Ty>& _Right) _THROW0() { // assign compatible _Right (assume pointer) reset(_Right.release()); return (*this); } auto_ptr<_Ty>& operator=(auto_ptr_ref<_Ty> _Right) _THROW0() { // assign compatible _Right._Ref (assume pointer) _Ty **_Pptr = (_Ty **)_Right._Ref; _Ty *_Ptr = *_Pptr; *_Pptr = 0; // release old reset(_Ptr); // set new return (*this); } What is the correct/standard behavior? How do other STL implementations behave?

  Read the article

• Why do i get exc bad access in cases when object is not nil?

  - by DixieFlatline

  I have an app that receives remote notifications. My view controller that is shown after push has a tableview. App crashes very randomly (1 in 20 tries) at line setting frame: if (!myTableView) { NSLog(@"self.myTableView is nil"); } myTableView.frame=CGRectMake(0, 70, 320, 376); This only happens when i open the app, then open some other apps and then receive the push notification. I guess it has something to do with memory. I use ARC (ios 5). The strange thing is that nslog is not displayed, so tableview is not nil. Crash log: Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Codes: KERN_INVALID_ADDRESS at 0x522d580c Crashed Thread: 0 Thread 0 name: Dispatch queue: com.apple.main-thread Thread 0 Crashed: 0 libobjc.A.dylib 0x352b1f7e objc_msgSend + 22 1 Foundation 0x37dc174c NSKVOPendingNotificationCreate + 216 2 Foundation 0x37dc1652 NSKeyValuePushPendingNotificationPerThread + 62 3 Foundation 0x37db3744 NSKeyValueWillChange + 408 4 Foundation 0x37d8a848 -[NSObject(NSKeyValueObserverNotification) willChangeValueForKey:] + 176 5 Foundation 0x37e0ca14 _NSSetPointValueAndNotify + 76 6 UIKit 0x312af25a -[UIScrollView(Static) _adjustContentOffsetIfNecessary] + 1890 7 UIKit 0x312cca54 -[UIScrollView setFrame:] + 548 8 UIKit 0x312cc802 -[UITableView setFrame:] + 182 9 POViO 0x000913cc -[FeedVC viewWillAppear:] (FeedVC.m:303) Dealloc is not called because it is not logged: - (void)dealloc { NSLog(@"dealloc"); }

  Read the article

• Map element position in data file to class property

  - by Augusto

  I need to read/write files, following a format provided by a third party specification. The specification itself is pretty simple: it says the position and the size of the data that will be saved in the file. For example: Position Size Description -------------------------------------------------- 0001 10 Device serial number 0011 02 Hour 0013 02 Minute 0015 02 Second 0017 02 Day 0019 02 Month 0021 02 Year The list is very long, it has about 400 elements. But lots of them can be combined. For example, hour, minute, second, day, month and year can be combined in a single DateTime object. I've splitted the elements into about 4 categories, and created separeted classes for holding the data. So, instead of a big structure representing the data, I have some smaller classes. I've also created different classes for reading and writing the data. The problem is: how to map the positions in the file to the objects properties, so that I don't need to repeat the values in the reading/writing class? I could use some custom attributes and retrieve them via reflection. But since the code will be running on devices with small memory and processor, it would be nice to find another way. My current read code looks like this: public void Read() { DataFile dataFile = new DataFile(); // the arguments are: position, size dataFile.SerialNumber = ReadLong(1, 10); //... } Any ideas on this one? Thanks!

  Read the article

• Source of UIView Implicit Animation delay?

  - by iPhoneToucher

  I have a block of UIView animation code that looks like this: [UIView beginAnimations:@"pushView" context:nil]; [UIView setAnimationDelay:0]; [UIView setAnimationDuration:.5]; [UIView setAnimationDelegate:self]; [UIView setAnimationWillStartSelector:@selector(animationWillStart)]; view.frame = CGRectMake(0, 0, 320, 416); [UIView commitAnimations]; The code basically mimics the animation of a ModalView presentation and is tied to a button on my interface. When the button is pressed, I get a long (.5 sec) delay (on iPod Touch...twice as fast on iPhone 3GS) before the animationWillStart: actually gets called. My app has lots going on besides this, but I've timed various points of my code and the delay definitely occurs at this block. In other words, a timestamp immediately before this code block and a timestamp when animationWillStart: gets called shows a .5 sec difference. I'm not too experienced with Core Animation and I'm just trying to figure out what the cause of the delay is...Memory use is stable when the animation starts and CoreAnimation FPS seems to be fine in Instruments. The view that gets animated does have upwards of 20 total subviews, but if that were the issue wouldn't it cause choppiness after the animation starts, rather than before? Any ideas?

  Read the article

• NHibernate.MappingException - Troubles Shooting Checklist (no persister for)

  - by Berryl

  Here's a starter list: 1) if hbm is hand generated, is it an embedded resource? 2) if using FNH, does it pass a PerssistenceSpecification test? 3) if not using FNH, can you save and then load the persisted class? 4) more? I'm sure many of you have gotten this one at one point or another. But have you ever gotten it when you knew your mapping was set up correctly? I started getting this exception after I started using a new repository design, but only in one scenario! PersistenceSpecification tests pass, as do all repository methods (using SQLite). The scenario that leads to the exception is when legacy projects from a different db are converted to green field system. The legacy system is from a different database and has it's own session factory, which should be irrelevant because the error comes after previously unconverted Projects are retrieved and in memory. As the routine tries to save these unconverted Projects into the new database, the exception is thrown, full stack trace below. Any ideas on how to build up the trouble shooting check list and solves this problem? Cheers, Berryl === the Exception trace ===== failed: NHibernate.MappingException : No persister for: Smack.ConstructionAdmin.Domain.Model.Projects.Project at NHibernate.Impl.SessionFactoryImpl.GetEntityPersister(String entityName) at NHibernate.Impl.SessionImpl.GetEntityPersister(String entityName, Object obj) at NHibernate.Engine.ForeignKeys.IsTransient(String entityName, Object entity, Nullable`1 assumed, ISessionImplementor session) at NHibernate.Event.Default.AbstractSaveEventListener.GetEntityState(Object entity, String entityName, EntityEntry entry, ISessionImplementor source) at NHibernate.Event.Default.DefaultSaveOrUpdateEventListener.PerformSaveOrUpdate(SaveOrUpdateEvent event) at NHibernate.Event.Default.DefaultSaveOrUpdateEventListener.OnSaveOrUpdate(SaveOrUpdateEvent event) at NHibernate.Impl.SessionImpl.FireSaveOrUpdate(SaveOrUpdateEvent event) at NHibernate.Impl.SessionImpl.SaveOrUpdate(Object obj) NHibernate\Repository\FabioNHibRepository.cs(46,0): at Smack.Core.Data.NHibernate.Repository.FabioNHibRepository`1.Add(T item) LegacyConversion\LegacyBatchUpdater.cs(20,0): at Smack.ConstructionAdmin.Data.LegacyConversion.LegacyBatchUpdater.ConvertOpenLegacyProjects(ILegacyProjectDao legacyProjectDao, IProjectRepository greenProjectRepository) Data\Brownfield\ProjectBatchUpdate_SQLiteTests.cs(19,0): at Smack.ConstructionAdmin.Tests.Data.Brownfield.ProjectBatchUpdate_SQLiteTests.Test()

  Read the article

< Previous Page | 457 458 459 460 461 462 463 464 465 466 467 468  | Next Page >