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  • wrapping user controls in a transaction

    - by Hans Gruber
    I'm working on heavily dynamic and configurable CMS system. Therefore, many pages are composed of a dynamically loaded set of user controls. To enable loose coupling between containers (pages) and children (user controls), all user controls are responsible for their own persistence. Each User Control is wired up to its data/service layer dependencies via IoC. They also implement an IPersistable interface, which allows the container .aspx page to issue a Save command to its children without knowledge of the number or exact nature of these user controls. Note: what follows is only pseudo-code: public class MyUserControl : IPersistable, IValidatable { public void Save() { throw new NotImplementedException(); } public bool IsValid() { throw new NotImplementedException(); } } public partial class MyPage { public void btnSave_Click(object sender, EventArgs e) { foreach (IValidatable control in Controls) { if (!control.IsValid) { throw new Exception("error"); } } foreach (IPersistable control in Controls) { if (!control.Save) { throw new Exception("error"); } } } } I'm thinking of using declarative transactions from the System.EnterpriseService namespace to wrap the btnSave_Click in a transaction in case of an exception, but I'm not sure how this might be achieved or any pitfalls to such an approach.

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  • What is a good DBMS for archiving?

    - by Thomas.Winsnes
    I've been stuck in a MsSql/MySql world now for a few years, and I've decided to spread my wings a little further. At the moment I'm researching which DBMS is good at things needed when archiving data. Eg. lots of writes and low reads. I've seen the NoSQL crusade, but I have a very RDBMS mindset, so I'm a bit skeptical. Anyone have any suggestions? Or even any pointers to where there are some benchmarks etc for this kind of stuff. Thank you :) Thomas

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  • how to load image from file using MFC

    - by Sweety Khan
    **my browse button code is void CFileOpenDlg::OnBnClickedButton1() { // TODO: Add your control notification handler code here CFileDialog dlg(TRUE); int result=dlg.DoModal(); if(result==IDOK) { path=dlg.GetPathName(); UpdateData(FALSE); } } and this is the code for loading an image from resource but tht does not work for loading an image from file. i know LoadImage(); is used for this but how? how can i edit this code to load image from file. Plzz help..... void CFileOpenDlg::OnBnClickedButton2() { // TODO: Add your control notification handler code here CRect r; CBitmap* m_bitmap; CDC dc, *pDC; BITMAP bmp; m_bitmap = new CBitmap(); m_bitmap-LoadBitmapW(IDB_BITMAP1); m_bitmap-GetBitmap(&bmp); pDC = this-GetDC(); dc.CreateCompatibleDC(pDC); dc.SelectObject(m_bitmap); pDC-BitBlt(200, 200, bmp.bmWidth, bmp.bmHeight, &dc,0 , 0, SRCCOPY); m_bitmap-DeleteObject(); m_bitmap-Detach(); } waiting for reply........**

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  • open encrypted file with php

    - by stormdrain
    Hi, I'm looking for a way to open encrypted files that are stored on a server. I'm using mcrypt to encrypt the files. I was initially going to create a class that would open the file, decrypt it, write it to a new location, then open that. But I have convinced myself there is a better way (I just don't know what it is). It seems like there should be a way to stream it (?) to the browser once it's decrypted. The initial setup would just link to the file location and the browser would take over (e.g. .pdf files would bring up a dialogue offering to open or save the file). If possible, I'd like it to do the same after decoding. Pointers? Advice? Bueller? Thanks!

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  • Improving field get and set performance with ASM

    - by ng
    I would like to avoid reflection in an open source project I am developing. Here I have classes like the following. public class PurchaseOrder { @Property private Customer customer; @Property private String name; } I scan for the @Property annotation to determine what I can set and get from the PurchaseOrder reflectively. There are many such classes all using java.lang.reflect.Field.get() and java.lang.reflect.Field.set(). Ideally I would like to generate for each property an invoker like the following. public interface PropertyAccessor<S, V> { public void set(S source, V value); public V get(S source); } Now when I scan the class I can create a static inner class of PurchaseOrder like so. static class customer_Field implements PropertyAccessor<PurchaseOrder, Customer> { public void set(PurchaseOrder order, Customer customer) { order.customer = customer; } public Customer get(PurchaseOrder order) { return order.customer; } } With these I totally avoid the cost of reflection. I can now set and get from my instances with native performance. Can anyone tell me how I would do this. A code example would be great. I have searched the net for a good example but can find nothing like this. The ASM examples are pretty poor also. The key here is that I have an interface that I can pass around. So I can have various implementations, perhaps one with Java Reflection as a default, one with ASM, and maybe one with Javassist? Any help would be greatly appreciated.

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  • how can I know current viewcontroller name in iphone

    - by Shikhar
    I have BaseView which implement UIViewController. Every view in project must implement this BaseView. In BaseView, I have method: -(void) checkLoginStatus { defaults = [[NSUserDefaults alloc] init]; if(![[defaults objectForKey:@"USERID"] length] > 0 ) { Login *login=[[Login alloc] initWithNibName:@"Login" bundle:nil]; [self.navigationController pushViewController:login animated:TRUE]; [login release]; } [defaults release]; } The problem is my Login view also implement BaseView, checks for login, and again open LoginView i.e. stuck in to recursive calling. Can I check in checkLoginStatus method if request is from LoginView then take no action else check login. Ex: (void) checkLoginStatus { if(SubView is NOT Login){ defaults = [[NSUserDefaults alloc] init]; if(![[defaults objectForKey:@"USERID"] length] 0 ) { Login *login=[[Login alloc] initWithNibName:@"Login" bundle:nil]; [self.navigationController pushViewController:login animated:TRUE]; [login release]; } [defaults release]; } } Please help..

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  • Checking instance of non-class constrained type parameter for null in generic method

    - by casperOne
    I currently have a generic method where I want to do some validation on the parameters before working on them. Specifically, if the instance of the type parameter T is a reference type, I want to check to see if it's null and throw an ArgumentNullException if it's null. Something along the lines of: // This can be a method on a generic class, it does not matter. public void DoSomething<T>(T instance) { if (instance == null) throw new ArgumentNullException("instance"); Note, I do not wish to constrain my type parameter using the class constraint. I thought I could use Marc Gravell's answer on "How do I compare a generic type to its default value?", and use the EqualityComparer<T> class like so: static void DoSomething<T>(T instance) { if (EqualityComparer<T>.Default.Equals(instance, null)) throw new ArgumentNullException("instance"); But it gives a very ambiguous error on the call to Equals: Member 'object.Equals(object, object)' cannot be accessed with an instance reference; qualify it with a type name instead How can I check an instance of T against null when T is not constrained on being a value or reference type?

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  • Custom User Management for Google App Engine Java

    - by Gopi
    I am using GAE Java for a multi-user application. There are multiple users with different roles. Each user can login, do some operations and logout. The business restricts me from using Google User Service and I need to implement my own for authentication and session management. Can anyone please share with me how should I go about implementing my own user management? I have read its very tricky to implement own user management. Any pointers in terms of best approaches/ design / existing frameworks if any ? I could see some similar posts but they are for python.

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  • iphone NSMutableArray loses objects at end of method

    - by Brodie4598
    Hello - in my app, an NSMutableArray is populated with an object in viewDidLoad (eventually there will be many objects but I'm just doing one til I get it working right). I also start a timer that starts a method that needs to access the NSMutableArray every few seconds. The NSMutableArray works fine in viewDidLoad, but as soon as that method is finished, it loses the object. myApp.h @interface MyApp : UIViewController { NSMutableArray *myMutableArray; NSTimer *timer; } @property (nonatomic, retain) NSMutableArray *myMutableArray; @property (nonatomic, retain) NSTimer *timer; @end myApp.m #import "MyApp.h" @implementation MyApp @synthesize myMutableArray; - (void) viewDidLoad { cycleTimer = [NSTimer scheduledTimerWithTimeInterval:4.0 target:self selector:@selector(newCycle) userInfo: nil repeats:YES]; MyObject *myCustomUIViewObject = [[MyObject alloc]init]; [myMutableArray addObject:myCustomUIViewObject]; [myCustomUIViewObject release]; NSLog(@"%i",[myMutableArray count]); /////outputs "1" } -(void) newCycle { NSLog(@"%i",[myMutableArray count]); /////outputs "0" ?? why is this?? }

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  • Add UIView Above All Other Views, Including StatusBar

    - by Mike Stead
    I'm wanting to create a view (UIControl) which blocks all input and shows a UIActivityIndicatorView while authenticating a user. The UIActionSheet and UIAlertView both manage to add a black semi-transparent view over the top of all other views to block input and I'd like to do similar. I've tried adding my view to the top UIWindow in the [[UIApplication sharedApplication] windows] array, and while this does place it above the UIKeyboard if it's visible, it doesn't place it over the StatusBar (which makes sense). My next attempt was to extend UIAlertView, remove all of its subviews and set its layer.contents = nil, then add the ActivityIndicator as a subview. This works well, but I can't seem to kill the default bouncy transition of the UIAlertView when you call it to "show". Does anyone have any pointers towards the best way tackle this problem that gives me full control? Oh and I know blocking input is not great but I do ensure it's for a short period of time and it has the benefit of making it clear to the user that their action, which must complete for them to progress, is processing.

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  • Threading.Timer invokes asynchronously many methods

    - by Dimitar
    Hi guys! Please help! I call a threading.timer from global.asax which invokes many methods each of which gets data from different services and writes it to files. My question is how do i make the methods to be invoked on a regular basis let's say 5 mins? What i do is: in Global.asax I declare a timer protected void Application_Start() { TimerCallback timerDelegate = new TimerCallback(myMainMethod); Timer mytimer = new Timer(timerDelegate, null, 0, 300000); Application.Add("timer", mytimer); } the declaration of myMainMethod looks like this: public static void myMainMethod(object obj) { MyDelegateType d1 = new MyDelegateType(getandwriteServiceData1); d1.BeginInvoke(null, null); MyDelegateType d2 = new MyDelegateType(getandwriteServiceData2); d2.BeginInvoke(null, null); } this approach works fine but it invokes myMainMethod every 5 mins. What I need is the method to be invoked 5 mins after all the data is retreaved and written to files on the server. How do I do that?

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  • Getting rid of nested using(...) statements

    - by Ghostrider
    Sometimes I need to use several disposable objects within a function. Most common case is having StreamReader and StreamWriter but sometimes it's even more than this. Nested using statements quickly add up and look ugly. To remedy this I've created a small class that collects IDisposable objects and disposes of them when it itself is disposed. public class MultiDispose : HashSet<IDisposable>, IDisposable { public MultiDispose(params IDisposable[] objectsToDispose) { foreach (IDisposable d in objectsToDispose) { this.Add(d); } } public T Add<T>(T obj) where T : IDisposable { base.Add(obj); return obj; } public void DisposeObject(IDisposable obj) { obj.Dispose(); base.Remove(obj); } #region IDisposable Members public void Dispose() { foreach (IDisposable d in this) { d.Dispose(); } } #endregion } So my code now looks like this: using (MultiDispose md = new MultiDispose()) { StreamReader rdr = md.Add(new StreamReader(args[0])); StreamWriter wrt = md.Add(new StreamWriter(args[1])); WhateverElseNeedsDisposing w = md.Add(new WhateverElseNeedsDisposing()); // code } Is there anything wrong with this approach that can cause problems down the road? I left the Remove function inherited from the HashSet on purpose so that the class would be more flexible. Surely misusing this function can lead to objects not being disposed of properly, but then there many other ways to shoot yourself in the foot without this class.

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  • Apache modules: C module vs mod_wsgi python module - Performance

    - by Gopal
    Hi A client of ours is asking us to implement a module in C in Apache webserver for performance reasons. This module should handle RESTful uri's, access a database and return results in json format. Many people here have recommended python mod_wsgi instead - but for simplicity of programming reasons. Can anyone tell me if there is a significant difference in performance between the mod_wsgi python solution vs. the Apache + C.module. Any anecdotes? Pointers to some study posted online?

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  • Getting a Specified Cast is not valid while importing data from Excel using Linq to SQL

    - by niceoneishere
    This is my second post. After learning from my first post how fantastic is to use Linq to SQL, I wanted to try to import data from a Excel sheet into my SQL database. First My Excel Sheet: it contains 4 columns namely ItemNo ItemSize ItemPrice UnitsSold I have a created a database table with the following fields table name ProductsSold Id int not null identity --with auto increment set to true ItemNo VarChar(10) not null ItemSize VarChar(4) not null ItemPrice Decimal(18,2) not null UnitsSold int not null Now I created a dal.dbml file based on my database and I am trying to import the data from excel sheet to db table using the code below. Everything is happening on click of a button. private const string forecast_query = "SELECT ItemNo, ItemSize, ItemPrice, UnitsSold FROM [Sheet1$]"; protected void btnUpload_Click(object sender, EventArgs e) { var importer = new LinqSqlModelImporter(); if (fileUpload.HasFile) { var uploadFile = new UploadFile(fileUpload.FileName); try { fileUpload.SaveAs(uploadFile.SavePath); if(File.Exists(uploadFile.SavePath)) { importer.SourceConnectionString = uploadFile.GetOleDbConnectionString(); importer.Import(forecast_query); gvDisplay.DataBind(); pnDisplay.Visible = true; } } catch (Exception ex) { Response.Write(ex.Source.ToString()); lblInfo.Text = ex.Message; } finally { uploadFile.DeleteFileNoException(); } } } // Now here is the code for LinqSqlModelImporter public class LinqSqlModelImporter : SqlImporter { public override void Import(string query) { // importing data using oledb command and inserting into db using LINQ to SQL using (var context = new WSDALDataContext()) { using (var myConnection = new OleDbConnection(base.SourceConnectionString)) using (var myCommand = new OleDbCommand(query, myConnection)) { myConnection.Open(); var myReader = myCommand.ExecuteReader(); while (myReader.Read()) { context.ProductsSolds.InsertOnSubmit(new ProductsSold() { ItemNo = myReader.GetString(0), ItemSize = myReader.GetString(1), ItemPrice = myReader.GetDecimal(2), UnitsSold = myReader.GetInt32(3) }); } } context.SubmitChanges(); } } } can someone please tell me where am I making the error or if I am missing something, but this is driving me nuts. When I debugged I am getting this error when casting from a number the value must be a number less than infinity I really appreciate it

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  • Dynamic stack allocation in C++

    - by Poni
    I want to allocate memory on the stack. Heard of _alloca / alloca and I understand that these are compiler-specific stuff, which I don't like. So, I came-up with my own solution (which might have it's own flaws) and I want you to review/improve it so for once and for all we'll have this code working: /*#define allocate_on_stack(pointer, size) \ __asm \ { \ mov [pointer], esp; \ sub esp, [size]; \ }*/ /*#define deallocate_from_stack(size) \ __asm \ { \ add esp, [size]; \ }*/ void test() { int buff_size = 4 * 2; char *buff = 0; __asm { // allocate mov [buff], esp; sub esp, [buff_size]; } // playing with the stack-allocated memory for(int i = 0; i < buff_size; i++) buff[i] = 0x11; __asm { // deallocate add esp, [buff_size]; } } void main() { __asm int 3h; test(); } Compiled with VC9. What flaws do you see in it? Me for example, not sure that subtracting from ESP is the solution for "any kind of CPU". Also, I'd like to make the commented-out macros work but for some reason I can't.

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  • How to refresh/redraw the screen (not the program window)

    - by mohrphium
    I'm having a bit of a hard time figuring out, how to remove a drawn ellipse after it has been drawn somewhere else. I need a circle to follow my mouse all the time and this is all the program should do. I get the mousepositions and draw my circle but how can I remove the last one? #include <Windows.h> #include <iostream> void drawRect(int a1, int a2){ HDC screenDC = ::GetDC(0); //Draw circle at mouse position ::Ellipse(screenDC, a1, a2+5, a1+9, a2+14); ::ReleaseDC(0, screenDC); //::InvalidateRect(0, NULL, TRUE); //<- I tried that but then everything flickers //Also, the refresh rate is not fast enough... still some circles left } int main(void) { int a1; int a2; bool exit=false; while (exit!=true) { POINT cursorPos; GetCursorPos(&cursorPos); float x = 0; x = cursorPos.x; float y = 0; y = cursorPos.y; a1=(int)cursorPos.x; a2=(int)cursorPos.y; drawRect(a1, a2); } } I am working with graphics and all that stuff for the first time. Im kinda stuck here... once again. Thanks.

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  • Problems with Json Serialize Dictionary<Enum, Int32>

    - by dbemerlin
    Hi, whenever i try to serialize the dictionary i get the exception: System.ArgumentException: Type 'System.Collections.Generic.Dictionary`2[[Foo.DictionarySerializationTest+TestEnum, Foo, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null],[System.Int32, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]]' is not supported for serialization/deserialization of a dictionary, keys must be strings or object My Testcase is: public class DictionarySerializationTest { private enum TestEnum { A, B, C } public void SerializationTest() { Dictionary<TestEnum, Int32> data = new Dictionary<TestEnum, Int32>(); data.Add(TestEnum.A, 1); data.Add(TestEnum.B, 2); data.Add(TestEnum.C, 3); JavaScriptSerializer serializer = new JavaScriptSerializer(); String result = serializer.Serialize(data); // Throws } public void SerializationStringTest() { Dictionary<String, Int32> data = new Dictionary<String, Int32>(); data.Add(TestEnum.A.ToString(), 1); data.Add(TestEnum.B.ToString(), 2); data.Add(TestEnum.C.ToString(), 3); JavaScriptSerializer serializer = new JavaScriptSerializer(); String result = serializer.Serialize(data); // Succeeds } } Of course i could use .ToString() whenever i enter something into the Dictionary but since it's used quite often in performance relevant methods i would prefer using the enum. My only solution is using .ToString() and converting before entering the performance critical regions but that is clumsy and i would have to change my code structure just to be able to serialize the data. Does anyone have an idea how i could serialize the dictionary as <Enum, Int32>? I use the System.Web.Script.Serialization.JavaScriptSerializer for serialization.

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  • Table and Image in a single page of QTextDocument in Qt4

    - by liaK
    Hi, I want to display a table and a image side by side. i.e Left side the image and right side the table. I want this because the image is the reference image for the data present in the table. I want that output in pdf. So I am using QTextDocument, QTextCursor and QPrinter to get the output in pdf. So how it is possible to display the image and table in QtextDocument i.e within a single page of the pdf? I am using Qt 4.5.3 and Windows Xp. Any pointers regarding this are welcome.

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  • Nmock2 and Event Expectations

    - by Kildareflare
    Im in the process of writing a test for a small application that follows the MVP pattern. Technically, I know I should have written the test before the code, but I needed to knock up a demo app quick smart and so im now going back to the test before moving on to the real development. In short I am attempting to test the presenter, however I cannot even get an empty test to run due to an Internal.ExpectationException. The exception is raised on a unexpected invocation of an event assignation. Here is the presenter class, public LBCPresenter(IView view, IModel model) { m_model = model; m_model.BatteryModifiedEvent += new EventHandler(m_model_BatteryModifiedEvent); } Model Interface public interface IModel { event EventHandler BatteryModifiedEvent; } And here is the test class, I can't see what im missing, ive told NMock to expect the event... [TestFixture] public class MVP_PresenterTester { private Mockery mocks; private IView _mockView; private IViewObserver _Presenter; private IModel _mockModel; [SetUp] public void SetUp() { mocks = new Mockery(); _mockView = mocks.NewMock<IView>(); _mockModel = mocks.NewMock<IModel>(); _Presenter = new LBCPresenter(_mockView, _mockModel); } [Test] public void TestClosingFormWhenNotDirty() { Expect.Once.On(_mockModel).EventAdd("BatteryModifiedEvent", NMock2.Is.Anything); //makes no difference if following line is commented out or not //mocks.VerifyAllExpectationsHaveBeenMet(); } } Every time I run the test I get the same expectation Exception. Any ideas?

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  • Why is my UITableView not being set?

    - by Jamie L
    I checked using the debbuger in the viewDidLoad method and tracerTableView is 0x0 which i assume means it is nil. I don't understand. I should go ahaed say yes I have already checked my nib file and yes all the connections are correct. Here is the header file and the begging of the .m. ///////////// .h file //////////// @interface TrackerListController : UITableViewController { // The mutable (modifiable) dictionary days holds all the data for the days tab NSMutableArray *trackerList; UITableView *tracerTableView; } @property (nonatomic, retain) NSMutableArray *trackerList; @property (nonatomic, retain) IBOutlet UITableView. *tracerTableView; //The addPackage: method is invoked when the user taps the addbutton created at runtime. -(void) addPackage : (id) sender; @end /////////////////////////////////////////////////////////////////////////////////////////////////// ////////////////////////////////////// .m file ////////////////////////////////////// @implementation TrackerListController @synthesize trackerList, tracerTableView; (void)viewDidLoad { [super viewDidLoad]; self.title = @"Package Tracker"; self.navigationItem.leftBarButtonItem = self.editButtonItem; UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(addPackage:)]; // Set up the Add custom button on the right of the navigation bar self.navigationItem.rightBarButtonItem = addButton; [addButton release]; // Release the addButton from memory since it is no longer needed }

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  • Change the playback rate of a track in real time on Android

    - by android_dev
    Hello, I would like to know if somebody knows a library to changing the playback rate of a track in real time. My idea is to load a track and change its playback rate to half or double. Firstly, I tried with MusicPlayer but is was not possible at all and then I tried with SoundPool. The problem is that with SoundPool I can´t change the rate once the track is loaded. Here is the code I am using (proof of concept): float j = 1; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button b = (Button)findViewById(R.id.Button01); b.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { j = (float) (j +.5); } }); AssetFileDescriptor afd; try { SoundPool sp = new SoundPool(1, AudioManager.STREAM_MUSIC, 0); afd = getAssets().openFd("wav/sample.wav"); int id = sp.load(afd, 1); sp.play(id, 1, 1, 1, 0, j); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } When I press the button, the playback rate should increase but it does not happen. Any idea of how change the rate in real time? Thanks in advance.

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  • run time error wats the wrong?

    - by javacode
    I am getting run time error import javax.mail.*; import javax.mail.internet.*; import java.util.*; public class SendMail { public static void main(String [] args)throws MessagingException { SendMail sm=new SendMail(); sm.postMail(new String[]{"[email protected]"},"hi","hello","[email protected]"); } public void postMail( String recipients[ ], String subject, String message , String from) throws MessagingException { boolean debug = false; //Set the host smtp address Properties props = new Properties(); props.put("mail.smtp.host", "webmail.emailmyname.com"); // create some properties and get the default Session Session session = Session.getDefaultInstance(props, null); session.setDebug(debug); // create a message Message msg = new MimeMessage(session); // set the from and to address InternetAddress addressFrom = new InternetAddress(from); msg.setFrom(addressFrom); InternetAddress[] addressTo = new InternetAddress[recipients.length]; for (int i = 0; i < recipients.length; i++) { addressTo[i] = new InternetAddress(recipients[i]); } msg.setRecipients(Message.RecipientType.TO, addressTo); // Optional : You can also set your custom headers in the Email if you Want msg.addHeader("MyHeaderName", "myHeaderValue"); // Setting the Subject and Content Type msg.setSubject(subject); msg.setContent(message, "text/plain"); Transport.send(msg); } } Error Exception in thread "main" java.lang.NoClassDefFoundError: SendMail Caused by: java.lang.ClassNotFoundException: SendMail at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) Could not find the main class: SendMail. Program will exit.

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  • How do you pass a BitmapImage from a background thread to the UI thread in WPF?

    - by DanM
    I have a background thread that generates a series of BitmapImage objects. Each time the background thread finishes generating a bitmap, I would like to show this bitmap to the user. The problem is figuring out how to pass the BitmapImage from the background thread to the UI thread. This is an MVVM project, so my view has an Image element: <Image Source="{Binding GeneratedImage}" /> My view-model has a property GeneratedImage: private BitmapImage _generatedImage; public BitmapImage GeneratedImage { get { return _generatedImage; } set { if (value == _generatedImage) return; _generatedImage= value; RaisePropertyChanged("GeneratedImage"); } } My view-model also has the code that creates the background thread: public void InitiateGenerateImages(List<Coordinate> coordinates) { ThreadStart generatorThreadStarter = delegate { GenerateImages(coordinates); }; var generatorThread = new Thread(generatorThreadStarter); generatorThread.ApartmentState = ApartmentState.STA; generatorThread.IsBackground = true; generatorThread.Start(); } private void GenerateImages(List<Coordinate> coordinates) { foreach (var coordinate in coordinates) { var backgroundThreadImage = GenerateImage(coordinate); // I'm stuck here...how do I pass this to the UI thread? } } I'd like to somehow pass backgroundThreadImage to the UI thread, where it will become uiThreadImage, then set GeneratedImage = uiThreadImage so the view can update. I've looked at some examples dealing with the WPF Dispatcher, but I can't seem to come up with an example that addresses this issue. Please advise.

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  • Learning C++ from scratch in Visual Studio?

    - by flesh
    I need to get up to speed with C++ quite quickly (I've never used it previously) - is learning through Visual Studio (i.e. Managed C++) going to be any use? Or will I end up learning the extensions and idiosyncracies of C++ in VS, rather then the language itself? If learning in VS is not recommended, what platform / IDE do you guys suggest? Edit: Can anyone elaborate on what VS will hide or manage for me when coding unmanaged C++? I really need to be learning things like pointers, garbage collection and all the nuts and bolts of the low level language.. does VS abstract or hide any of this kind of stuff from you? Thanks for all the suggestions..

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  • Why the performance of following code is degrading when I use threads ?

    - by DotNetBeginner
    Why the performance of following code is degrading when I use threads ? **1.Without threads int[] arr = new int[100000000]; //Array elements - [0][1][2][3]---[100000000-1] addWithOutThreading(arr); // Time required for this operation - 1.16 sec Definition for addWithOutThreading public void addWithOutThreading(int[] arr) { UInt64 result = 0; for (int i = 0; i < 100000000; i++) { result = result + Convert.ToUInt64(arr[i]); } Console.WriteLine("Addition = " + result.ToString()); } **2.With threads int[] arr = new int[100000000]; int part = (100000000 / 4); UInt64 res1 = 0, res2 = 0, res3 = 0, res4 = 0; ThreadStart starter1 = delegate { addWithThreading(arr, 0, part, ref res1); }; ThreadStart starter2 = delegate { addWithThreading(arr, part, part * 2, ref res2); }; ThreadStart starter3 = delegate { addWithThreading(arr, part * 2, part * 3, ref res3); }; ThreadStart starter4 = delegate { addWithThreading(arr, part * 3, part * 4, ref res4); }; Thread t1 = new Thread(starter1); Thread t2 = new Thread(starter2); Thread t3 = new Thread(starter3); Thread t4 = new Thread(starter4); t1.Start(); t2.Start(); t3.Start(); t4.Start(); t1.Join(); t2.Join(); t3.Join(); t4.Join(); Console.WriteLine("Addition = "+(res1+res2+res3+res4).ToString()); // Time required for this operation - 1.30 sec Definition for addWithThreading public void addWithThreading(int[] arr,int startIndex, int endIndex,ref UInt64 result) { for (int i = startIndex; i < endIndex; i++) { result = result + Convert.ToUInt64(arr[i]); } }

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