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  • Exit code 3 (not my return value, looking for source)

    - by Kathoz
    Greetings, my program exits with the code 3. No error messages, no exceptions, and the exit is not initiated by my code. The problem occurs when I am trying to read extremely long integer values from a text file (the text file is present and correctly opened, with successful prior reading). I am using very large amounts of memory (in fact, I think that this might be the cause, as I am nearly sure I go over the 2GB per process memory limit). I am also using the GMP (or, rather, MPIR) library to multiply bignums. I am fairly sure that this is not a file I/O problem as I got the same error code on a previous program version that was fully in-memory. System: MS Visual Studio 2008 MS Windows Vista Home Premium x86 MPIR 2.1.0 rc2 4GB RAM Where might this error code originate from? EDIT: this is the procedure that exits with the code void condenseBinSplitFile(const char *sourceFilename, int partCount){ //condense results file into final P and Q std::string tempFilename; std::string inputFilename(sourceFilename); std::string outputFilename(BIN_SPLIT_FILENAME_DATA2); mpz_class *P = new mpz_class(0); mpz_class *Q = new mpz_class(0); mpz_class *PP = new mpz_class(0); mpz_class *QQ = new mpz_class(0); FILE *sourceFile; FILE *resultFile; fpos_t oldPos; int swapCount = 0; while (partCount > 1){ std::cout << partCount << std::endl; sourceFile = fopen(inputFilename.c_str(), "r"); resultFile = fopen(outputFilename.c_str(), "w"); for (int i=0; i<partCount/2; i++){ //Multiplication order: //Get Q, skip P //Get QQ, mul Q and QQ, print Q, delete Q //Jump back to P, get P //Mul P and QQ, delete QQ //Skip QQ, get PP //Mul P and PP, delete P and PP //Get Q, skip P mpz_inp_str(Q->get_mpz_t(), sourceFile, CALC_BASE); fgetpos(sourceFile, &oldPos); skipLine(sourceFile); skipLine(sourceFile); //Get QQ, mul Q and QQ, print Q, delete Q mpz_inp_str(QQ->get_mpz_t(), sourceFile, CALC_BASE); (*Q) *= (*QQ); mpz_out_str(resultFile, CALC_BASE, Q->get_mpz_t()); fputc('\n', resultFile); (*Q) = 0; //Jump back to P, get P fsetpos(sourceFile, &oldPos); mpz_inp_str(P->get_mpz_t(), sourceFile, CALC_BASE); //Mul P and QQ, delete QQ (*P) *= (*QQ); (*QQ) = 0; //Skip QQ, get PP skipLine(sourceFile); skipLine(sourceFile); mpz_inp_str(PP->get_mpz_t(), sourceFile, CALC_BASE); //Mul P and PP, delete PP, print P, delete P (*P) += (*PP); (*PP) = 0; mpz_out_str(resultFile, CALC_BASE, P->get_mpz_t()); fputc('\n', resultFile); (*P) = 0; } partCount /= 2; fclose(sourceFile); fclose(resultFile); //swap filenames tempFilename = inputFilename; inputFilename = outputFilename; outputFilename = tempFilename; swapCount++; } delete P; delete Q; delete PP; delete QQ; remove(BIN_SPLIT_FILENAME_RESULTS); if (swapCount%2 == 0) rename(sourceFilename, BIN_SPLIT_FILENAME_RESULTS); else rename(BIN_SPLIT_FILENAME_DATA2, BIN_SPLIT_FILENAME_RESULTS); }

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  • opengl - Rendering multiple cubes

    - by opiop65
    I have this code (Doesn't work at all) static void initGl() { glViewport(0, 0, Display.getWidth(), Display.getHeight()); glMatrixMode(GL_PROJECTION); glLoadIdentity(); GLU.gluPerspective(45.0f, Display.getWidth() / Display.getHeight(), 1.0f, 1000.0f); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glClearColor(0.0f, 0.0f, 0.0f, 0.0f); glClearDepth(1.0f); glDepthFunc(GL_LEQUAL); glEnable(GL_DEPTH_TEST); glShadeModel(GL_SMOOTH); glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); } public static void renderGL() { glViewport(0, 0, Display.getWidth(), Display.getHeight()); glClearColor(0.0f, 0.0f, 0.0f, 0.5f); glLoadIdentity(); glTranslatef(0.0f, 0.0f, -60.0f); drawCube(); } public static void drawCube() { for (int x = 0; x < 100; x++) { for (int y = 0; y < 100; y++) { for (int z = 0; z < 100; z++) { glBegin(GL_QUADS); glColor3f(1, 0, 0); glVertex3f(-x, -y, z); glVertex3f(x, -y, z); glVertex3f(x, y, z); glVertex3f(-x, y, z); glColor3f(1, 0, 1); glVertex3f(x, -y, -z); glVertex3f(-x, -y, -z); glVertex3f(-x, y, -z); glVertex3f(x, y, -z); glColor3f(1, 1, 1); glVertex3f(-x, y, z); glVertex3f(x, y, z); glVertex3f(x, y, -z); glVertex3f(-x, y, -z); glColor3f(0, 0, 1); glVertex3f(x, -y, z); glVertex3f(-x, -y, z); glVertex3f(-x, -y, -z); glVertex3f(x, -y, -z); glColor3f(1, 1, 0); glVertex3f(x, -y, z); glVertex3f(x, -y, -z); glVertex3f(x, y, -z); glVertex3f(x, y, z); glColor3f(0, 2, 1); glVertex3f(-x, -y, -z); glVertex3f(-x, -y, z); glVertex3f(-x, y, z); glVertex3f(-x, y, -z); glEnd(); } } } All it does it freeze up the program and eventually it will render the red side of the cube. This obviously has to do with gltranslatef, but I don't know why that isn't working. My question is, how do I render multiple cubes at once? Are there any tutorials out there on voxel engines? Sorry for the horrible code, I realize I probably need a array to do this. I'm quite new at opengl.

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  • Java algorithm for normalizing audio

    - by Marty Pitt
    I'm trying to normalize an audio file of speech. Specifically, where an audio file contains peaks in volume, I'm trying to level it out, so the quiet sections are louder, and the peaks are quieter. I know very little about audio manipulation, beyond what I've learnt from working on this task. Also, my math is embarrassingly weak. I've done some research, and the Xuggle site provides a sample which shows reducing the volume using the following code: (full version here) @Override public void onAudioSamples(IAudioSamplesEvent event) { // get the raw audio byes and adjust it's value ShortBuffer buffer = event.getAudioSamples().getByteBuffer().asShortBuffer(); for (int i = 0; i < buffer.limit(); ++i) buffer.put(i, (short)(buffer.get(i) * mVolume)); super.onAudioSamples(event); } Here, they modify the bytes in getAudioSamples() by a constant of mVolume. Building on this approach, I've attempted a normalisation modifies the bytes in getAudioSamples() to a normalised value, considering the max/min in the file. (See below for details). I have a simple filter to leave "silence" alone (ie., anything below a value). I'm finding that the output file is very noisy (ie., the quality is seriously degraded). I assume that the error is either in my normalisation algorithim, or the way I manipulate the bytes. However, I'm unsure of where to go next. Here's an abridged version of what I'm currently doing. Step 1: Find peaks in file: Reads the full audio file, and finds this highest and lowest values of buffer.get() for all AudioSamples @Override public void onAudioSamples(IAudioSamplesEvent event) { IAudioSamples audioSamples = event.getAudioSamples(); ShortBuffer buffer = audioSamples.getByteBuffer().asShortBuffer(); short min = Short.MAX_VALUE; short max = Short.MIN_VALUE; for (int i = 0; i < buffer.limit(); ++i) { short value = buffer.get(i); min = (short) Math.min(min, value); max = (short) Math.max(max, value); } // assign of min/max ommitted for brevity. super.onAudioSamples(event); } Step 2: Normalize all values: In a loop similar to step1, replace the buffer with normalized values, calling: buffer.put(i, normalize(buffer.get(i)); public short normalize(short value) { if (isBackgroundNoise(value)) return value; short rawMin = // min from step1 short rawMax = // max from step1 short targetRangeMin = 1000; short targetRangeMax = 8000; int abs = Math.abs(value); double a = (abs - rawMin) * (targetRangeMax - targetRangeMin); double b = (rawMax - rawMin); double result = targetRangeMin + ( a/b ); // Copy the sign of value to result. result = Math.copySign(result,value); return (short) result; } Questions: Is this a valid approach for attempting to normalize an audio file? Is my math in normalize() valid? Why would this cause the file to become noisy, where a similar approach in the demo code doesn't?

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  • How to upload Image on Android?

    - by Mattiah85
    I havve to upload image from my SD card to PHP server. I have read a lot of articles and topics but I have some problems... First I have use that code: HttpURLConnection connection = null; DataOutputStream outputStream = null; //DataInputStream inputStream = null; String urlServer = hostName+"Upload"; String lineEnd = "\r\n"; String twoHyphens = "--"; String boundary = "*****"; String serverResponseMessage; //int serverResponseCode; int bytesRead, bytesAvailable, bufferSize; byte[] buffer; int maxBufferSize = 1*1024*1024; try { showLog("uploading file: " + file); FileInputStream fileInputStream = new FileInputStream(new File(pictureFileDir+"/"+file) ); URL url = new URL(urlServer); connection = (HttpURLConnection) url.openConnection(); // Allow Inputs &amp; Outputs. connection.setDoInput(true); connection.setDoOutput(true); connection.setUseCaches(false); // Set HTTP method to POST. connection.setRequestMethod("POST"); connection.setRequestProperty("Connection", "Keep-Alive"); connection.setRequestProperty("Content-Type", "multipart/form-data;boundary="+boundary); outputStream = new DataOutputStream( connection.getOutputStream() ); outputStream.writeBytes(twoHyphens + boundary + lineEnd); outputStream.writeBytes("Content-Disposition: form-data; name=\"uploaded_file\";filename=\"" + file +"\"" + lineEnd); outputStream.writeBytes(lineEnd); bytesAvailable = fileInputStream.available(); bufferSize = Math.min(bytesAvailable, maxBufferSize); buffer = new byte[bufferSize]; // Read file bytesRead = fileInputStream.read(buffer, 0, bufferSize); while (bytesRead > 0) { outputStream.write(buffer, 0, bufferSize); bytesAvailable = fileInputStream.available(); bufferSize = Math.min(bytesAvailable, maxBufferSize); bytesRead = fileInputStream.read(buffer, 0, bufferSize); } outputStream.writeBytes(lineEnd); outputStream.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd); // Responses from the server (code and message) //serverResponseCode = connection.getResponseCode(); serverResponseMessage = connection.getResponseMessage(); showLog("server response: " + serverResponseMessage); fileInputStream.close(); outputStream.flush(); outputStream.close(); } catch (Exception ex) { ex.printStackTrace(); } but server response 200/OK and no file was on destination server... After i have read about Multipart: try { HttpParams params = new BasicHttpParams(); params.setParameter(CoreProtocolPNames.PROTOCOL_VERSION, HttpVersion.HTTP_1_1); DefaultHttpClient mHttpClient = new DefaultHttpClient(params); File image = new File(pictureFileDir + "/" + filename); HttpPost httppost = new HttpPost(hostName+"Upload"); MultipartEntity multipartEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE); multipartEntity.addPart("Image", new FileBody(image)); httppost.setEntity(multipartEntity); mHttpClient.execute(httppost, new PhotoUploadResponseHandler()); } catch (Exception e) { e.printStackTrace(); } but then a i have such LOG in LogCat and nothing else... 06-04 06:50:52.277: D/dalvikvm(1584): DexOpt: couldn't find static field Lorg/apache/http/message/BasicHeaderValueParser;.INSTANCE 06-04 06:50:52.277: W/dalvikvm(1584): VFY: unable to resolve static field 6688 (INSTANCE) in Lorg/apache/http/message/BasicHeaderValueParser; 06-04 06:50:52.277: D/dalvikvm(1584): VFY: replacing opcode 0x62 at 0x001b ServerSide Script: $target_path = "uploads"; $target_path = $target_path . basename( $_FILES['Image']); if(move_uploaded_file($_FILES['tmp_name'], $file_path)) { echo "success"; } else{ echo "fail"; } why? What is the simplest way to upload image?

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  • non blocking client server chat application in java using nio

    - by Amith
    I built a simple chat application using nio channels. I am very much new to networking as well as threads. This application is for communicating with server (Server / Client chat application). My problem is that multiple clients are not supported by the server. How do I solve this problem? What's the bug in my code? public class Clientcore extends Thread { SelectionKey selkey=null; Selector sckt_manager=null; public void coreClient() { System.out.println("please enter the text"); BufferedReader stdin=new BufferedReader(new InputStreamReader(System.in)); SocketChannel sc = null; try { sc = SocketChannel.open(); sc.configureBlocking(false); sc.connect(new InetSocketAddress(8888)); int i=0; while (!sc.finishConnect()) { } for(int ii=0;ii>-22;ii++) { System.out.println("Enter the text"); String HELLO_REQUEST =stdin.readLine().toString(); if(HELLO_REQUEST.equalsIgnoreCase("end")) { break; } System.out.println("Sending a request to HelloServer"); ByteBuffer buffer = ByteBuffer.wrap(HELLO_REQUEST.getBytes()); sc.write(buffer); } } catch (IOException e) { e.printStackTrace(); } finally { if (sc != null) { try { sc.close(); } catch (Exception e) { e.printStackTrace(); } } } } public void run() { try { coreClient(); } catch(Exception ej) { ej.printStackTrace(); }}} public class ServerCore extends Thread { SelectionKey selkey=null; Selector sckt_manager=null; public void run() { try { coreServer(); } catch(Exception ej) { ej.printStackTrace(); } } private void coreServer() { try { ServerSocketChannel ssc = ServerSocketChannel.open(); try { ssc.socket().bind(new InetSocketAddress(8888)); while (true) { sckt_manager=SelectorProvider.provider().openSelector(); ssc.configureBlocking(false); SocketChannel sc = ssc.accept(); register_server(ssc,SelectionKey.OP_ACCEPT); if (sc == null) { } else { System.out.println("Received an incoming connection from " + sc.socket().getRemoteSocketAddress()); printRequest(sc); System.err.println("testing 1"); String HELLO_REPLY = "Sample Display"; ByteBuffer buffer = ByteBuffer.wrap(HELLO_REPLY.getBytes()); System.err.println("testing 2"); sc.write(buffer); System.err.println("testing 3"); sc.close(); }}} catch (IOException e) { e.printStackTrace(); } finally { if (ssc != null) { try { ssc.close(); } catch (IOException e) { e.printStackTrace(); } } } } catch(Exception E) { System.out.println("Ex in servCORE "+E); } } private static void printRequest(SocketChannel sc) throws IOException { ReadableByteChannel rbc = Channels.newChannel(sc.socket().getInputStream()); WritableByteChannel wbc = Channels.newChannel(System.out); ByteBuffer b = ByteBuffer.allocate(1024); // read 1024 bytes while (rbc.read(b) != -1) { b.flip(); while (b.hasRemaining()) { wbc.write(b); System.out.println(); } b.clear(); } } public void register_server(ServerSocketChannel ssc,int selectionkey_ops)throws Exception { ssc.register(sckt_manager,selectionkey_ops); }} public class HelloClient { public void coreClientChat() { Clientcore t=new Clientcore(); new Thread(t).start(); } public static void main(String[] args)throws Exception { HelloClient cl= new HelloClient(); cl.coreClientChat(); }} public class HelloServer { public void coreServerChat() { ServerCore t=new ServerCore(); new Thread(t).start(); } public static void main(String[] args) { HelloServer st= new HelloServer(); st.coreServerChat(); }}

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  • Can't get Jacobi algorithm to work in Objective-C

    - by Chris Long
    Hi, For some reason, I can't get this program to work. I've had other CS majors look at it and they can't figure it out either. This program performs the Jacobi algorithm (you can see step-by-step instructions and a MATLAB implementation here). BTW, it's different from the Wikipedia article of the same name. Since NSArray is one-dimensional, I added a method that makes it act like a two-dimensional C array. After running the Jacobi algorithm many times, the diagonal entries in the NSArray (i[0][0], i[1][1], etc.) are supposed to get bigger and the others approach 0. For some reason though, they all increase exponentially. For instance, i[2][4] should equal 0.0000009, not 9999999, while i[2][2] should be big. Thanks in advance, Chris NSArray+Matrix.m @implementation NSArray (Matrix) @dynamic offValue, transposed; - (double)offValue { double sum = 0.0; for ( MatrixItem *item in self ) if ( item.nonDiagonal ) sum += pow( item.value, 2.0 ); return sum; } - (NSMutableArray *)transposed { NSMutableArray *transpose = [[[NSMutableArray alloc] init] autorelease]; int i, j; for ( i = 0; i < 5; i++ ) { for ( j = 0; j < 5; j++ ) { [transpose addObject:[self objectAtRow:j andColumn:i]]; } } return transpose; } - (id)objectAtRow:(NSUInteger)row andColumn:(NSUInteger)column { NSUInteger index = 5 * row + column; return [self objectAtIndex:index]; } - (NSMutableArray *)multiplyWithMatrix:(NSArray *)array { NSMutableArray *result = [[NSMutableArray alloc] init]; int i = 0, j = 0, k = 0; double value; for ( i = 0; i < 5; i++ ) { value = 0.0; for ( j = 0; j < 5; j++ ) { for ( k = 0; k < 5; k++ ) { MatrixItem *firstItem = [self objectAtRow:i andColumn:k]; MatrixItem *secondItem = [array objectAtRow:k andColumn:j]; value += firstItem.value * secondItem.value; } MatrixItem *item = [[MatrixItem alloc] initWithValue:value]; item.row = i; item.column = j; [result addObject:item]; } } return result; } @end Jacobi_AlgorithmAppDelegate.m // ... - (void)jacobiAlgorithmWithEntry:(MatrixItem *)entry { MatrixItem *b11 = [matrix objectAtRow:entry.row andColumn:entry.row]; MatrixItem *b22 = [matrix objectAtRow:entry.column andColumn:entry.column]; double muPlus = ( b22.value + b11.value ) / 2.0; muPlus += sqrt( pow((b22.value - b11.value), 2.0) + 4.0 * pow(entry.value, 2.0) ); Vector *u1 = [[[Vector alloc] initWithX:(-1.0 * entry.value) andY:(b11.value - muPlus)] autorelease]; [u1 normalize]; Vector *u2 = [[[Vector alloc] initWithX:-u1.y andY:u1.x] autorelease]; NSMutableArray *g = [[[NSMutableArray alloc] init] autorelease]; for ( int i = 0; i <= 24; i++ ) { MatrixItem *item = [[[MatrixItem alloc] init] autorelease]; if ( i == 6*entry.row ) item.value = u1.x; else if ( i == 6*entry.column ) item.value = u2.y; else if ( i == ( 5*entry.row + entry.column ) || i == ( 5*entry.column + entry.row ) ) item.value = u1.y; else if ( i % 6 == 0 ) item.value = 1.0; else item.value = 0.0; [g addObject:item]; } NSMutableArray *firstResult = [[g.transposed multiplyWithMatrix:matrix] autorelease]; matrix = [firstResult multiplyWithMatrix:g]; } // ...

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  • I want to write a program to control the square moving by using WINAPI

    - by code_new
    This is the code as attempted so far: #include <windows.h> LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ; int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) { static TCHAR szAppname[] = TEXT ("win0") ; WNDCLASS wndclass ; MSG msg ; HWND hwnd ; wndclass.style = CS_HREDRAW | CS_VREDRAW ; wndclass.cbWndExtra = 0 ; wndclass.cbClsExtra = 0 ; wndclass.lpfnWndProc = WndProc ; wndclass.lpszClassName = szAppname ; wndclass.lpszMenuName = NULL ; wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ; wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ; wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ; wndclass.hInstance = hInstance ; if (!RegisterClass (&wndclass)) { MessageBox (NULL, TEXT ("Register fail"), szAppname, 0) ; return 0 ; } hwnd = CreateWindow ( szAppname, TEXT ("mywin"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL) ; ShowWindow (hwnd, iCmdShow) ; UpdateWindow (hwnd) ; while (GetMessage (&msg, NULL, 0, 0)) { TranslateMessage (&msg) ; DispatchMessage (&msg) ; } return msg.wParam ; } LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) { static int cxClient, cyClient, Left, Top, Right, Down ; PAINTSTRUCT ps ; HDC hdc ; RECT rect ; Right = 20 ; Down = 20 ; switch (message) { case WM_SIZE : cxClient = LOWORD (lParam) ; cyClient = HIWORD (lParam) ; return 0 ; case WM_PAINT : hdc = BeginPaint (hwnd, &ps) ; SetRect (&rect, Left, Top, Right, Down) ; FillRect (hdc, &rect, CreateSolidBrush (RGB (100, 100, 100))) ; EndPaint (hwnd, &ps) ; return 0 ; case WM_KEYDOWN : InvalidateRect (hwnd, &rect, TRUE) ; switch (wParam) { case VK_UP : if (Top - 20 < 0) { Top = 0 ; Down = 20 ; } else { Top -= 20 ; Down -= 20 ; } SendMessage (hwnd, WM_PAINT, wParam, lParam) ; break ; case VK_DOWN : if (Down + 20 > cyClient) { Down = cyClient ; Top = Down - 20 ; } else { Down += 20 ; Top += 20 ; }SendMessage (hwnd, WM_PAINT, wParam, lParam) ; break ; case VK_LEFT : if (Left - 20 < 0) { Left = 0 ; Right = 20 ; } else { Left -= 20 ; Right -= 20 ; }SendMessage (hwnd, WM_PAINT, wParam, lParam) ; break ; case VK_RIGHT : if (Right + 20 > cxClient) { Right = cxClient ; Left = Right - 20 ; } else { Right += 20 ; Left += 20 ; }SendMessage (hwnd, WM_PAINT, wParam, lParam) ; break ; default : break ; } return 0 ; case WM_DESTROY : PostQuitMessage (0) ; return 0 ; } return DefWindowProc (hwnd, message, wParam, lParam); } I considered that I didn't deal the message well, so I can't control it.

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  • texture colours opengl

    - by user1324894
    Hi I am making a simple 2D game in c++ and for the map I am doing texture mapping by using tiles and assigning textures to those tiles. However, when I run the programme the textures become black and white when I want them to be the colour they are in the .png image. This is my code: int worldMap[10][10] = { {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, }; void background() { glClearColor(0.0,0.0,0.0,0.0); /**********************************************************************************************/ // Texture loading object nv::Image img; // Return true on success if(img.loadImageFromFile("Image_Loading/field.png")) { glGenTextures(1, &myTexture); glBindTexture(GL_TEXTURE_2D, myTexture); glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE); glTexImage2D(GL_TEXTURE_2D, 0, img.getInternalFormat(), img.getWidth(), img.getHeight(), 0, img.getFormat(), img.getType(), img.getLevel(0)); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT ); glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT ); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, 16.0f); } else MessageBox(NULL, "Failed to load texture", "End of the world", MB_OK | MB_ICONINFORMATION); /**********************************************************************************************/ } void drawTiles (void) { //our function to draw the tiles for (int i = 0; i < 10; i++) //loop through the height of the map { for (int j = 0; j < 10; j++) //loop through the width of the map { if (worldMap[i][j] == 0) //if the map at this position contains a 0 { glBindTexture( GL_TEXTURE_2D, myTexture ); //bind our grass texture to our shape } glPushMatrix(); //push the matrix so that our translations only affect this tile glTranslatef(j, -i, 0); //translate the tile to where it should belong glBegin (GL_QUADS); //begin drawing our quads glTexCoord2d(10, 0); glVertex2f((-10 + mapX),(-10 + mapY)); //with our vertices we have to assign a texcoord glTexCoord2d(10, 0); glVertex2f((10 + mapX),(-10 + mapY)); //so that our texture has some points to draw to glTexCoord2d(10, 10); glVertex2f((10 + mapX),(10 + mapY)); glTexCoord2d(0, 10); glVertex2f((-10 + mapX),(10 + mapY)); glEnd(); glPopMatrix(); //pop the matrix } //end first loop } //end second loop } void display() { glClearColor (0.0,0.0,0.0,1.0); glClear(GL_COLOR_BUFFER_BIT); /**********************************************************************************************/ glMatrixMode( GL_PROJECTION ); glLoadIdentity(); gluOrtho2D( -5, 5, -5, 5); glMatrixMode( GL_MODELVIEW ); glEnable(GL_TEXTURE_2D); glBindTexture(GL_TEXTURE_2D, myTexture); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); drawTiles(); glDisable(GL_TEXTURE_2D); glDisable(GL_BLEND); /**********************************************************************************************/ } void character () { glBegin(GL_POLYGON); glVertex2f((-0.5+characterX),(-0.5 +characterY)); glVertex2f((-0.5+characterX),(0.5+characterY)); glVertex2f((0.5+characterX),(0.5+characterY)); glVertex2f((0.5+characterX),(-0.5+characterY)); glTranslatef(characterX, characterY, 0.0f); glEnd(); } Can anybody help please?

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  • NHibernate: How is identity Id updated when saving a transient instance?

    - by bretddog
    If I use session-per-transaction and call: session.SaveOrUpdate(entity) corrected: session.SaveOrUpdateCopy(entity) ..and entity is a transient instance with identity-Id=0. Shall the above line automatically update the Id of the entity, and make the instance persistent? Or should it do so on transaction.Commit? Or do I have to somehow code that explicitly? Obviously the Id of the database row (new, since transient) is autogenerated and saved as some number, but I'm talking about the actual parameter instance here. Which is the business logic instance. EDIT Mappings: public class StoreMap : ClassMap<Store> { public StoreMap() { Id(x => x.Id).GeneratedBy.Identity(); Map(x => x.Name); HasMany(x => x.Staff) // 1:m .Cascade.All(); HasManyToMany(x => x.Products) // m:m .Cascade.All() .Table("StoreProduct"); } } public class EmployeeMap : ClassMap<Employee> { public EmployeeMap() { Id(x => x.Id).GeneratedBy.Identity(); Map(x => x.FirstName); Map(x => x.LastName); References(x => x.Store); // m:1 } } public class ProductMap : ClassMap<Product> { public ProductMap() { Id(x => x.Id).GeneratedBy.Identity(); Map(x => x.Name).Length(20); Map(x => x.Price).CustomSqlType("decimal").Precision(9).Scale(2); HasManyToMany(x => x.StoresStockedIn) .Cascade.All() .Inverse() .Table("StoreProduct"); } } EDIT2 Class definitions: public class Store { public int Id { get; private set; } public string Name { get; set; } public IList<Product> Products { get; set; } public IList<Employee> Staff { get; set; } public Store() { Products = new List<Product>(); Staff = new List<Employee>(); } // AddProduct & AddEmployee is required. "NH needs you to set both sides before // it will save correctly" public void AddProduct(Product product) { product.StoresStockedIn.Add(this); Products.Add(product); } public void AddEmployee(Employee employee) { employee.Store = this; Staff.Add(employee); } } public class Employee { public int Id { get; private set; } public string FirstName { get; set; } public string LastName { get; set; } public Store Store { get; set; } } public class Product { public int Id { get; private set; } public string Name { get; set; } public decimal Price { get; set; } public IList<Store> StoresStockedIn { get; private set; } }

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  • Accessing Layout Items from inside Widget AppWidgetProvider

    - by cam4mav
    I am starting to go insane trying to figure this out. It seems like it should be very easy, I'm starting to wonder if it's possible. What I am trying to do is create a home screen widget, that only contains an ImageButton. When it is pressed, the idea is to change some setting (like the wi-fi toggle) and then change the Buttons image. I have the ImageButton declared like this in my main.xml <ImageButton android:id="@+id/buttonOne" android:src="@drawable/button_normal_ringer" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" /> my AppWidgetProvider class, named ButtonWidget * note that the RemoteViews class is a locally stored variable. this allowed me to get access to the RViews layout elements... or so I thought. @Override public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) { remoteViews = new RemoteViews(context.getPackageName(), R.layout.main); Intent active = new Intent(context, ButtonWidget.class); active.setAction(VIBRATE_UPDATE); active.putExtra("msg","TESTING"); PendingIntent actionPendingIntent = PendingIntent.getBroadcast(context, 0, active, 0); remoteViews.setOnClickPendingIntent(R.id.buttonOne, actionPendingIntent); appWidgetManager.updateAppWidget(appWidgetIds, remoteViews); } @Override public void onReceive(Context context, Intent intent) { // v1.5 fix that doesn't call onDelete Action final String action = intent.getAction(); Log.d("onReceive",action); if (AppWidgetManager.ACTION_APPWIDGET_DELETED.equals(action)) { final int appWidgetId = intent.getExtras().getInt( AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID); if (appWidgetId != AppWidgetManager.INVALID_APPWIDGET_ID) { this.onDeleted(context, new int[] { appWidgetId }); } } else { // check, if our Action was called if (intent.getAction().equals(VIBRATE_UPDATE)) { String msg = "null"; try { msg = intent.getStringExtra("msg"); } catch (NullPointerException e) { Log.e("Error", "msg = null"); } Log.d("onReceive",msg); if(remoteViews != null){ Log.d("onReceive",""+remoteViews.getLayoutId()); remoteViews.setImageViewResource(R.id.buttonOne, R.drawable.button_pressed_ringer); Log.d("onReceive", "tried to switch"); } else{ Log.d("F!", "--naughty language used here!!!--"); } } super.onReceive(context, intent); } } so, I've been testing this and the onReceive method works great, I'm able to send notifications and all sorts of stuff (removed from code for ease of reading) the one thing I can't do is change any properties of the view elements. To try and fix this, I made RemoteViews a local and static private variable. Using log's I was able to see that When multiple instances of the app are on screen, they all refer to the one instance of RemoteViews. perfect for what I'm trying to do The trouble is in trying to change the image of the ImageButton. I can do this from within the onUpdate method using this. remoteViews.setImageViewResource(R.id.buttonOne, R.drawable.button_pressed_ringer); that doesn't do me any good though once the widget is created. For some reason, even though its inside the same class, being inside the onReceive method makes that line not work. That line used to throw a Null pointer as a matter of fact, until I changed the variable to static. now it passes the null test, refers to the same layoutId as it did at the start, reads the line, but it does nothing. Its like the code isn't even there, just keeps chugging along. SO...... Is there any way to modify layout elements from within a widget after the widget has been created!? I want to do this based on the environment, not with a configuration activity launch. I've been looking at various questions and this seems to be an issue that really hasn't been solved, such as link text and link text oh and for anyone who finds this and wants a good starting tutorial for widgets, this is easy to follow (though a bit old, it gets you comfortable with widgets) .pdf link text hopefully someone can help here. I kinda have the feeling that this is illegal and there is a different way to go about this. I would LOVE to be told another approach!!!! Thanks

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  • Learning to implement DIC in MVC

    - by Tom
    I am learning to apply DIC to MVC project. So, I have sketched this DDD-ish DIC-ready-ish layout to my best understanding. I have read many blogs articles wikis for the last few days. However, I am not confident about implementing it correctly. Could you please demonstrate to me how to put them into DIC the proper way? I prefer Ninject or Windsor after all the readings, but anyDIC will do as long as I can get the correct idea how to do it. Web controller... public class AccountBriefingController { //create private IAccountServices accountServices { get; set; } public AccountBriefingController(IAccountServices accsrv) accountServices = accsrv; } //do work public ActionResult AccountBriefing(string userid, int days) { //get days of transaction records for this user BriefingViewModel model = AccountServices.GetBriefing(userid, days); return View(model); } } View model ... public class BriefingViewModel { //from user repository public string UserId { get; set; } public string AccountNumber {get; set;} public string FirstName { get; set; } public string LastName { get; set; } //from account repository public string Credits { get; set; } public List<string> Transactions { get; set; } } Service layer ... public interface IAccountServices { BriefingViewModel GetBriefing(); } public class AccountServices { //create private IUserRepository userRepo {get; set;} private IAccountRepository accRepo {get; set;} public AccountServices(UserRepository ur, AccountRepository ar) { userRepo = ur; accRepo = ar; } //do work public BriefingViewModel GetBriefing(string userid, int days) { var model = new BriefingViewModel(); //<---is that okay to new a model here?? var user = userRepo.GetUser(userid); if(user != null) { model.UserId = userid; model.AccountNumber = user.AccountNumber; model.FirstName = user.FirstName; model.LastName = user.LastName; //account records model.Credits = accRepo.GetUserCredits(userid); model.Transactions = accRepo.GetUserTransactions(userid, days); } return model; } } Domain layer and data models... public interface IUserRepository { UserDataModel GetUser(userid); } public interface IAccountRepository { List<string> GetUserTransactions(userid, days); int GetUserCredits(userid); } // Entity Framework DBContext goes under here Please point out if my implementation is wrong, e.g.I can feel in AccountServices-GetBriefing - new BriefingViewModel() seems wrong to me, but I don't know how to fit the stud into DIC? Thank you very much for your help!

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  • How to select chosen columns from two different entities into one DTO using NHibernate?

    - by Pawel Krakowiak
    I have two classes (just recreating the problem): public class User { public virtual int Id { get; set; } public virtual string FirstName { get; set; } public virtual string LastName { get; set; } public virtual IList<OrgUnitMembership> OrgUnitMemberships { get; set; } } public class OrgUnitMembership { public virtual int UserId { get; set; } public virtual int OrgUnitId { get; set; } public virtual DateTime JoinDate { get; set; } public virtual DateTime LeaveDate { get; set; } } There's a Fluent NHibernate map for both, of course: public class UserMapping : ClassMap<User> { public UserMapping() { Table("Users"); Id(e => e.Id).GeneratedBy.Identity(); Map(e => e.FirstName); Map(e => e.LastName); HasMany(x => x.OrgUnitMemberships) .KeyColumn(TypeReflector<OrgUnitMembership> .GetPropertyName(p => p.UserId))).ReadOnly().Inverse(); } } public class OrgUnitMembershipMapping : ClassMap<OrgUnitMembership> { public OrgUnitMembershipMapping() { Table("OrgUnitMembership"); CompositeId() .KeyProperty(x=>x.UserId) .KeyProperty(x=>x.OrgUnitId); Map(x => x.JoinDate); Map(x => x.LeaveDate); References(oum => oum.OrgUnit) .Column(TypeReflector<OrgUnitMembership> .GetPropertyName(oum => oum.OrgUnitId)).ReadOnly(); References(oum => oum.User) .Column(TypeReflector<OrgUnitMembership> .GetPropertyName(oum => oum.UserId)).ReadOnly(); } } What I want to do is to retrieve some users based on criteria, but I would like to combine all columns from the Users table with some columns from the OrgUnitMemberships table, analogous to a SQL query: select u.*, m.JoinDate, m.LeaveDate from Users u inner join OrgUnitMemberships m on u.Id = m.UserId where m.OrgUnitId = :ouid I am totally lost, I tried many different options. Using a plain SQL query almost works, but because there are some nullable enums in the User class AliasToBean fails to transform, otherwise wrapping a SQL query would work like this: return Session .CreateSQLQuery(sql) .SetParameter("ouid", orgUnitId) .SetResultTransformer(Transformers.AliasToBean<UserDTO>()) .List<UserDTO>() I tried the code below as a test (a few different variants), but I'm not sure what I'm doing. It works partially, I get instances of UserDTO back, the properties coming from OrgUnitMembership (dates) are filled, but all properties from User are null: User user = null; OrgUnitMembership membership = null; UserDTO dto = null; var users = Session.QueryOver(() => user) .SelectList(list => list .Select(() => user.Id) .Select(() => user.FirstName) .Select(() => user.LastName)) .JoinAlias(u => u.OrgUnitMemberships, () => membership) //.JoinQueryOver<OrgUnitMembership>(u => u.OrgUnitMemberships) .SelectList(list => list .Select(() => membership.JoinDate).WithAlias(() => dto.JoinDate) .Select(() => membership.LeaveDate).WithAlias(() => dto.LeaveDate)) .TransformUsing(Transformers.AliasToBean<UserDTO>()) .List<UserDTO>();

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  • Application stops on back button in new activity

    - by Bruno Almeida
    I have this application, that have a listView, and when I click in a item on listView, it opens a new activity. That works fine! But, if I open the new activity and than press the "back button" the application "Unfortunately, has stopped". Is there something I'm doing wrong? Here is my code: First activity: public class AndroidSQLite extends Activity { private SQLiteAdapter mySQLiteAdapter; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); ListView listContent = (ListView)findViewById(R.id.contentlist); mySQLiteAdapter = new SQLiteAdapter(this); mySQLiteAdapter.openToRead(); Cursor cursor = mySQLiteAdapter.queueAll(); startManagingCursor(cursor); String[] from = new String[]{SQLiteAdapter.KEY_NOME,SQLiteAdapter.KEY_ID}; int[] to = new int[]{R.id.text,R.id.id}; SimpleCursorAdapter cursorAdapter = new SimpleCursorAdapter(this, R.layout.row, cursor, from, to); listContent.setAdapter(cursorAdapter); listContent.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView<?> parent, View view, int position, long id) { Toast.makeText(getBaseContext(), id + "", Toast.LENGTH_LONG).show(); Intent details = new Intent(getApplicationContext(),DetailsPassword.class); startActivity(details); } }); mySQLiteAdapter.close(); } } Second Activity: public class DetailsPassword extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); TextView text = new TextView(getApplicationContext()); text.setText("Text to show"); setContentView(text); } } // ===== EDITED ===== here is the Stack Track 10-30 08:55:05.744: E/AndroidRuntime(28046): FATAL EXCEPTION: main 10-30 08:55:05.744: E/AndroidRuntime(28046): java.lang.RuntimeException: Unable to resume activity {com.example.sqliteexemple2/com.example.sqliteexemple2.AndroidSQLite}: java.lang.IllegalStateException: trying to requery an already closed cursor android.database.sqlite.SQLiteCursor@4180a370 10-30 08:55:05.744: E/AndroidRuntime(28046): at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2701) 10-30 08:55:05.744: E/AndroidRuntime(28046): at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2729) 10-30 08:55:05.744: E/AndroidRuntime(28046): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1250) 10-30 08:55:05.744: E/AndroidRuntime(28046): at android.os.Handler.dispatchMessage(Handler.java:99) 10-30 08:55:05.744: E/AndroidRuntime(28046): at android.os.Looper.loop(Looper.java:137) 10-30 08:55:05.744: E/AndroidRuntime(28046): at android.app.ActivityThread.main(ActivityThread.java:4931) 10-30 08:55:05.744: E/AndroidRuntime(28046): at java.lang.reflect.Method.invokeNative(Native Method) 10-30 08:55:05.744: E/AndroidRuntime(28046): at java.lang.reflect.Method.invoke(Method.java:511) 10-30 08:55:05.744: E/AndroidRuntime(28046): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791) 10-30 08:55:05.744: E/AndroidRuntime(28046): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:558) 10-30 08:55:05.744: E/AndroidRuntime(28046): at dalvik.system.NativeStart.main(Native Method) 10-30 08:55:05.744: E/AndroidRuntime(28046): Caused by: java.lang.IllegalStateException: trying to requery an already closed cursor android.database.sqlite.SQLiteCursor@4180a370 10-30 08:55:05.744: E/AndroidRuntime(28046): at android.app.Activity.performRestart(Activity.java:5051) 10-30 08:55:05.744: E/AndroidRuntime(28046): at android.app.Activity.performResume(Activity.java:5074) 10-30 08:55:05.744: E/AndroidRuntime(28046): at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2691) 10-30 08:55:05.744: E/AndroidRuntime(28046): ... 10 more

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  • BadPaddingException in Android encrypt

    - by DarthRoman
    Hi everyone, I am making an Android application, and I want to encrypt a String before sending it to a DataBase, and encrytpion is correct. The problem is when I am going to decrypt the String, because I get a BadPaddingException and I have no idea where the problem is. Here is the code: public final static String HEX = "36A52C8FB7DF9A3F"; public static String encrypt(String seed, String cleartext) throws Exception { byte[] rawKey = getRawKey(seed.getBytes()); byte[] result = encrypt(rawKey, cleartext.getBytes()); return toHex(result); } public static String decrypt(String seed, String encrypted) throws Exception { byte[] rawKey = getRawKey(seed.getBytes()); byte[] enc = toByte(encrypted); byte[] result = decrypt(rawKey, enc); return new String(result); } public static String toHex(String txt) { return toHex(txt.getBytes()); } public static String fromHex(String hex) { return new String(toByte(hex)); } public static byte[] toByte(String hexString) { int len = hexString.length()/2; byte[] result = new byte[len]; for (int i = 0; i < len; i++) result[i] = Integer.valueOf(hexString.substring(2*i, 2*i+2), 16).byteValue(); return result; } public static String toHex(byte[] buf) { if (buf == null) return ""; StringBuffer result = new StringBuffer(2*buf.length); for (int i = 0; i < buf.length; i++) { appendHex(result, buf[i]); } return result.toString(); } private static byte[] getRawKey(byte[] seed) throws Exception { KeyGenerator kgen = KeyGenerator.getInstance("AES"); SecureRandom sr = SecureRandom.getInstance("SHA1PRNG"); sr.setSeed(seed); kgen.init(128, sr); // 192 and 256 bits may not be available SecretKey skey = kgen.generateKey(); byte[] raw = skey.getEncoded(); return raw; } private static byte[] encrypt(byte[] raw, byte[] clear) throws Exception { SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES"); Cipher cipher = Cipher.getInstance("AES"); cipher.init(Cipher.ENCRYPT_MODE, skeySpec); byte[] encrypted = cipher.doFinal(clear); return encrypted; } private static byte[] decrypt(byte[] raw, byte[] encrypted) throws Exception { SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES"); Cipher cipher = Cipher.getInstance("AES"); cipher.init(Cipher.DECRYPT_MODE, skeySpec); byte[] decrypted = cipher.doFinal(encrypted); return decrypted; } private static void appendHex(StringBuffer sb, byte b) { sb.append(HEX.charAt((b>>4)&0x0f)).append(HEX.charAt(b&0x0f)); } I encrypt and decrypt with this code: String encrypted = encrypt(HEX, "some text"); String decrypted = decrypt(HEX, encrypted); Can anyone help me please? Thank you very much!!

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  • WCF/REST Get image into picturebox?

    - by Garrith
    So I have wcf rest service which succesfuly runs from a console app, if I navigate to: http://localhost:8000/Service/picture/300/400 my image is displayed note the 300/400 sets the width and height of the image within the body of the html page. The code looks like this: namespace WcfServiceLibrary1 { [ServiceContract] public interface IReceiveData { [OperationContract] [WebInvoke(Method = "GET", BodyStyle = WebMessageBodyStyle.Wrapped, ResponseFormat = WebMessageFormat.Xml, UriTemplate = "picture/{width}/{height}")] Stream GetImage(string width, string height); } public class RawDataService : IReceiveData { public Stream GetImage(string width, string height) { int w, h; if (!Int32.TryParse(width, out w)) { w = 640; } // Handle error if (!Int32.TryParse(height, out h)) { h = 400; } Bitmap bitmap = new Bitmap(w, h); for (int i = 0; i < bitmap.Width; i++) { for (int j = 0; j < bitmap.Height; j++) { bitmap.SetPixel(i, j, (Math.Abs(i - j) < 2) ? Color.Blue : Color.Yellow); } } MemoryStream ms = new MemoryStream(); bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg); ms.Position = 0; WebOperationContext.Current.OutgoingResponse.ContentType = "image/jpeg"; return ms; } } } What I want to do now is use a client application "my windows form app" and add that image into a picturebox. Im abit stuck as to how this can be achieved as I would like the width and height of the image from my wcf rest service to be set by the width and height of the picturebox. I have tryed this but on two of the lines have errors and im not even sure if it will work as the code for my wcf rest service seperates width and height with a "/" if you notice in the url. string uri = "http://localhost:8080/Service/picture"; private void button1_Click(object sender, EventArgs e) { StringBuilder sb = new StringBuilder(); sb.AppendLine("<picture>"); sb.AppendLine("<width>" + pictureBox1.Image.Width + "</width>"); // the url looks like this http://localhost:8080/Service/picture/300/400 when accessing the image so I am trying to set this here sb.AppendLine("<height>" + pictureBox1.Image.Height + "</height>"); sb.AppendLine("</picture>"); string picture = sb.ToString(); byte[] getimage = Encoding.UTF8.GetBytes(picture); // not sure this is right HttpWebRequest req = WebRequest.Create(uri); //cant convert webrequest to httpwebrequest req.Method = "GET"; req.ContentType = "image/jpg"; req.ContentLength = getimage.Length; MemoryStream reqStrm = req.GetRequestStream(); //cant convert IO stream to IO Memory stream reqStrm.Write(getimage, 0, getimage.Length); reqStrm.Close(); HttpWebResponse resp = req.GetResponse(); // cant convert web respone to httpwebresponse MessageBox.Show(resp.StatusDescription); pictureBox1.Image = Image.FromStream(reqStrm); reqStrm.Close(); resp.Close(); } So just wondering if some one could help me out with this futile attempt at adding a variable image size from my rest service to a picture box on button click. This is the host app aswell: namespace ConsoleApplication1 { class Program { static void Main(string[] args) { string baseAddress = "http://" + Environment.MachineName + ":8000/Service"; ServiceHost host = new ServiceHost(typeof(RawDataService), new Uri(baseAddress)); host.AddServiceEndpoint(typeof(IReceiveData), new WebHttpBinding(), "").Behaviors.Add(new WebHttpBehavior()); host.Open(); Console.WriteLine("Host opened"); Console.ReadLine();

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  • "assignment makes integer from pointer without a cast " warning in c

    - by mekasperasky
    #include<stdio.h> /* this is a lexer which recognizes constants , variables ,symbols, identifiers , functions , comments and also header files . It stores the lexemes in 3 different files . One file contains all the headers and the comments . Another file will contain all the variables , another will contain all the symbols. */ int main() { int i=0,j; char a,b[20],c[30]; FILE *fp1,*fp2; c[0]='"if"; c[1]="then"; c[2]="else"; c[3]="switch"; c[4]="printf"; c[5]="scanf"; c[6]="NULL"; c[7]="int"; c[8]="char"; c[9]="float"; c[10]="long"; c[11]="double"; c[12]="char"; c[13]="const"; c[14]="continue"; c[15]="break"; c[16]="for"; c[17]="size of"; c[18]="register"; c[19]="short"; c[20]="auto"; c[21]="while"; c[22]="do"; c[23]="case"; fp1=fopen("source.txt","r"); //the source file is opened in read only mode which will passed through the lexer fp2=fopen("lext.txt","w"); //now lets remove all the white spaces and store the rest of the words in a file if(fp1==NULL) { perror("failed to open source.txt"); //return EXIT_FAILURE; } i=0; while(!feof(fp1)) { a=fgetc(fp1); if(a!=' ') { b[i]=a; } else { for (j=0;j<23;j++) { if(c[j]==b) { fprintf(fp2, "%.20s\n", c[j]); continue ; } b[i]='\0'; fprintf(fp2, "%.20s\n", b); i=0; continue; } //else if //{ i=i+1; /*Switch(a) { case EOF :return eof; case '+':sym=sym+1; case '-':sym=sym+1; case '*':sym=sym+1; case '/':sym=sym+1; case '%':sym=sym+1; case ' */ } fclose(fp1); fclose(fp2); return 0; } This is my c code for lexical analysis .. its giving warnings and also not writing anything into the lext file ..

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  • Get the Dynamic table data from gui in selenium webDriver

    - by Rabindra
    I am working on a web based Application that I am testing with Selenium. On one page the content is dynamically loaded in table. I want to get the Table data, i am geting a "org.openqa.selenium.NullPointerElementException" in this line. WebElement table = log.driver.findElement(By.xpath(tableXpath)); I tried the following complete code. public int selectfromtable(String tableXpath, String CompareValue, int columnnumber) throws Exception { WebElement table = log.driver.findElement(By.xpath(tableXpath)); List<WebElement> rows = table.findElements(By.tagName("tr")); int flag = 0; for (WebElement row : rows) { List<WebElement> cells = row.findElements(By.tagName("td")); if (!cells.isEmpty() && cells.get(columnnumber).getText().equals(CompareValue)) { flag = 1; Thread.sleep(1000); break; } else { Thread.sleep(2000); flag = 0; } } return flag; } I am calling the above method like String tableXpath = ".//*[@id='event_list']/form/div[1]/table/tbody/tr/td/div/table"; selectfromtable(tableXpath, eventType, 3); my html page is like <table width="100%"> <tbody style="overflow: auto; background-color: #FFFFFF"> <tr class="trOdd"> <td width="2%" align="center"> <td width="20%" align="center"> Account </td> <td width="20%" align="center"> Enter Collection </td> <td width="20%" align="center"> <td width="20%" align="center"> 10 </td> <td width="20%" align="center"> 1 </td> </tr> </tbody> <tbody style="overflow: auto; background-color: #FFFFFF"> <tr class="trEven"> <td width="2%" align="center"> <td width="20%" align="center"> Account </td> <td width="20%" align="center"> Resolved From Collection </td> <td width="20%" align="center"> <td width="20%" align="center"> 10 </td> <td width="20%" align="center"> 1 </td> </tr> </tbody> </table>

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  • Binary operator overloading on a templated class (C++)

    - by GRB
    Hi all, I was recently trying to gauge my operator overloading/template abilities and as a small test, created the Container class below. While this code compiles fine and works correctly under MSVC 2008 (displays 11), both MinGW/GCC and Comeau choke on the operator+ overload. As I trust them more than MSVC, I'm trying to figure out what I'm doing wrong. Here is the code: #include <iostream> using namespace std; template <typename T> class Container { friend Container<T> operator+ <> (Container<T>& lhs, Container<T>& rhs); public: void setobj(T ob); T getobj(); private: T obj; }; template <typename T> void Container<T>::setobj(T ob) { obj = ob; } template <typename T> T Container<T>::getobj() { return obj; } template <typename T> Container<T> operator+ <> (Container<T>& lhs, Container<T>& rhs) { Container<T> temp; temp.obj = lhs.obj + rhs.obj; return temp; } int main() { Container<int> a, b; a.setobj(5); b.setobj(6); Container<int> c = a + b; cout << c.getobj() << endl; return 0; } This is the error Comeau gives: Comeau C/C++ 4.3.10.1 (Oct 6 2008 11:28:09) for ONLINE_EVALUATION_BETA2 Copyright 1988-2008 Comeau Computing. All rights reserved. MODE:strict errors C++ C++0x_extensions "ComeauTest.c", line 27: error: an explicit template argument list is not allowed on this declaration Container<T> operator+ <> (Container<T>& lhs, Container<T>& rhs) ^ 1 error detected in the compilation of "ComeauTest.c". I'm having a hard time trying to get Comeau/MingGW to play ball, so that's where I turn to you guys. It's been a long time since my brain has melted this much under the weight of C++ syntax, so I feel a little embarrassed ;). Thanks in advance. EDIT: Eliminated an (irrelevant) lvalue error listed in initial Comeau dump.

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  • Why is there a Null Pointer Exception in this Java Code?

    - by algorithmicCoder
    This code takes in users and movies from two separate files and computes a user score for a movie. When i run the code I get the following error: Exception in thread "main" java.lang.NullPointerException at RecommenderSystem.makeRecommendation(RecommenderSystem.java:75) at RecommenderSystem.main(RecommenderSystem.java:24) I believe the null pointer exception is due to an error in this particular class but I can't spot it....any thoughts? import java.io.*; import java.lang.Math; public class RecommenderSystem { private Movie[] m_movies; private User[] m_users; /** Parse the movies and users files, and then run queries against them. */ public static void main(String[] argv) throws FileNotFoundException, ParseError, RecommendationError { FileReader movies_fr = new FileReader("C:\\workspace\\Recommender\\src\\IMDBTop10.txt"); FileReader users_fr = new FileReader("C:\\workspace\\Recommender\\src\\IMDBTop10-users.txt"); MovieParser mp = new MovieParser(movies_fr); UserParser up = new UserParser(users_fr); Movie[] movies = mp.getMovies(); User[] users = up.getUsers(); RecommenderSystem rs = new RecommenderSystem(movies, users); System.out.println("Alice would rate \"The Shawshank Redemption\" with at least a " + rs.makeRecommendation("The Shawshank Redemption", "asmith")); System.out.println("Carol would rate \"The Dark Knight\" with at least a " + rs.makeRecommendation("The Dark Knight", "cd0")); } /** Instantiate a recommender system. * * @param movies An array of Movie that will be copied into m_movies. * @param users An array of User that will be copied into m_users. */ public RecommenderSystem(Movie[] movies, User[] users) throws RecommendationError { m_movies = movies; m_users = users; } /** Suggest what the user with "username" would rate "movieTitle". * * @param movieTitle The movie for which a recommendation is made. * @param username The user for whom the recommendation is made. */ public double makeRecommendation(String movieTitle, String username) throws RecommendationError { int userNumber; int movieNumber; int j=0; double weightAvNum =0; double weightAvDen=0; for (userNumber = 0; userNumber < m_users.length; ++userNumber) { if (m_users[userNumber].getUsername().equals(username)) { break; } } for (movieNumber = 0; movieNumber < m_movies.length; ++movieNumber) { if (m_movies[movieNumber].getTitle().equals(movieTitle)) { break; } } // Use the weighted average algorithm here (don't forget to check for // errors). while(j<m_users.length){ if(j!=userNumber){ weightAvNum = weightAvNum + (m_users[j].getRating(movieNumber)- m_users[j].getAverageRating())*(m_users[userNumber].similarityTo(m_users[j])); weightAvDen = weightAvDen + (m_users[userNumber].similarityTo(m_users[j])); } j++; } return (m_users[userNumber].getAverageRating()+ (weightAvNum/weightAvDen)); } } class RecommendationError extends Exception { /** An error for when something goes wrong in the recommendation process. * * @param s A string describing the error. */ public RecommendationError(String s) { super(s); } }

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  • UIScrollView message handler

    - by cs221313
    Hi, all, I want to create a scroll view and put thumbnail view in that scroll view. but I can not get the touchBegan message in my program. My source code is like following. - (void)viewDidLoad { [super viewDidLoad]; NSError* error; NSString *bundleRoot = [[NSBundle mainBundle] bundlePath]; dirContents = [[[NSFileManager defaultManager] contentsOfDirectoryAtPath:bundleRoot error: &error] copy]; scrollView = [[UIScrollView alloc] initWithFrame:[[self view] bounds]]; scrollView.pagingEnabled = YES; scrollView.showsHorizontalScrollIndicator = NO; scrollView.userInteractionEnabled = YES; scrollView.clipsToBounds = YES; // default is NO, we want to restrict drawing within our scrollview scrollView.scrollEnabled = YES; [scrollView setDelegate:self]; [[self view] addSubview:scrollView]; DLog(@"scroll frame top = %d, left = %d, width = %d, height = %d", scrollView.frame.origin.x, scrollView.frame.origin.y, scrollView.frame.size.width, scrollView.frame.size.height); int i, j; UIView* onePageView = [[UIView alloc] init]; int pageNumber = 0; int iconNumber = 0; for (NSString *tString in dirContents) { if ([tString hasSuffix:@"_chess.png"]) { if(iconNumber == 9) { onePageView.tag = pageNumber + 1; [scrollView addSubview: onePageView]; onePageView = [[UIView alloc] init]; pageNumber++; iconNumber = 0; } j = iconNumber % 3; i = iconNumber / 3; const float WIDTH = 150.0; const float HEIGHT = 150.0; CGRect imageRect = CGRectMake(j * 200 + 50.0, i * 200 + 50.0, WIDTH, HEIGHT); //remove the charactors of "_chess.png". NSString* sgfName = [tString substringToIndex: tString.length - 10]; sgfName = [sgfName stringByAppendingString: @".sgf"]; ThumbnailView *thumbnailImage = [[ThumbnailView alloc] initWithFilename: sgfName frame: imageRect]; thumbnailImage.delegate = self; [thumbnailImage setImage:[UIImage imageNamed: tString]]; thumbnailImage.opaque = YES; // explicitly opaque for performance //[self.view addSubview:thumbnailImage]; [onePageView addSubview:thumbnailImage]; [thumbnailImage release]; iconNumber++; } } pageControl.numberOfPages = pageNumber + 1; pageControl.currentPage = 0; onePageView.tag = pageNumber + 1; [scrollView addSubview: onePageView]; [self layoutScrollPages]; } ThumbnailView class is like following. // // ThumbnailView.m // go // // Created by David Li on 2/18/11. // Copyright 2011 __MyCompanyName__. All rights reserved. // #import "common.h" #import "ThumbnailView.h" #import "ipad_goViewController.h" @implementation ThumbnailView @synthesize delegate; @synthesize sgfName; -(id) initWithFilename: (NSString*)filename frame: (CGRect)frame { sgfName = [[NSString alloc] initWithString: filename]; return [self initWithFrame: frame]; } - (id)initWithFrame:(CGRect)frame { self = [super initWithFrame:frame]; if (self) { // Initialization code. self.userInteractionEnabled = YES; } return self; } - (void)viewDidAppear:(BOOL)animated { [super viewDidAppear:animated]; [self becomeFirstResponder]; } /* refer to http://stackoverflow.com/questions/855095/how-can-i-detect-the-touch-event-of-an-uiimageview */ -(BOOL)canBecomeFirstResponder { return YES; } - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { DLog(@"touched"); [[self delegate] loadGame: sgfName]; } /* // Only override drawRect: if you perform custom drawing. // An empty implementation adversely affects performance during animation. - (void)drawRect:(CGRect)rect { // Drawing code. } */ - (void)dealloc { [super dealloc]; } @end I can not catch the touchesBegan message in my program. Can anyone help me? I stucked by this problem by couple days. Thanks so much.

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  • Need help in creating test appliaction in Java and passing parameters into a new designed Java API.

    - by Christophe
    Need help, Please!!! By following the protocol, the Request should be built in 5 byte length, including 1 byte for changing Braud rate (Speed), and send request to a RS-232 port. Protocol: --------------- Request for the command processing, with optional extra byte for changing Baud Rate: LGT : length message ( LGT = 5 ) TYPE : 0x06 TO(time out): 0x0000 CMD : (1 byte) 0x02 application update Baud Rate : (1 byte) 0xNN (optional parameter to change baud rate of the Mnt App) where NN can be: 0x00 = No Baud Rate Change (similar to 4-byte command above) 0x09 = Change to 9600 Baud for Application Update speed 0x0A = Change to 19200 Baud for Application Update speed 0x0E = Change to 115200 Baud for Application Update speed All other bytes are not accepted and will result in a status of 0x01. ------------------ I'm trying to test if my code works or not by creating another class (TestApplication.java) and pass the "3 differenr Baut rate" to this CPXAppliaction. the 3 Baud Rate is supposed to input by reading a file.txt. Question: How do you think these code (first half)? please don't warry about the details about the "sending part". I mean, do I need setter/getter for the "speed" parameter pass? I created the demo test class DemoApp.java (input speed by reading a txt file, and pass into CPXAppliaction). how do you think about that code? Many thanks to you guys!! public class CPXApplication extends CPXCommand { private int speed; . public CPXApplication() { speed = 9600; } public CPXApplication(int speedinit) { speed = speedinit; // TODO: where to get the speed? } protected void buildRequest() throws ElitePortException { String trans = ""; // build the full-qualified message following the protocol trans = addToRequest(trans, (char) 0); trans = addToRequest(trans, (char) 5); trans = addToRequest(trans, (char) 6); trans = addToRequest(trans, (char) 0); trans = addToRequest(trans, (char) 0); trans = addToRequest(trans, (char) 2); switch (speed) { case 9600: trans = addToRequest(trans, (char) 0x09); break; case 19200: trans = addToRequest(trans, (char) 0x0A); break; case 115200: trans = addToRequest(trans, (char) 0x0E); break; default: // TODO: unexpected baud rate. throw(); break; } trans = EncryptBinary(trans); trans = "F0." + trans; wrapRequest(trans); } protected String addToRequest(String req, char c) { return req + c; } protected String addToRequest(String req, String s) { return req + s; } protected String addToRequest(String req) { return req; } public void analyzeResponse() { //.............. } } Here is the demo test code: package com.ingenico.testApp; import com.ingenico.EliteFd.; import java.util.Scanner; import java.io.; class Run { public static void run() { CPXAppliactionUpdate input = new CpXApplicationUpdate(); int lineno = 0; try { FileReader fr = new FileReader("baudRateSpeed.txt"); BufferedReader reader = new BufferedReader(fr); String line = reader.readLine(); Scanner scan = null; while (line != null) { scan = new Scanner(line); String speed; speed = scan.next(); if (lineno == 0) { input.speed = speed; lineno++; } else { input = cpxapplicationupdate(speed, input); } line = reader.readLine(); } reader.close(); } catch (FileNotFoundException e) { System.out.println("Could not find the file"); } catch (IOException e) { System.out.println("Had a problem reading from file"); } } public class DemoApp{ public void main(String args[]) { run(); } } }

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  • Many to many self join through junction table

    - by Peter
    I have an EF model that can self-reference through an intermediary class to define a parent/child relationship. I know how to do a pure many-to-many relationship using the Map command, but for some reason going through this intermediary class is causing problems with my mappings. The intermediary class provides additional properties for the relationship. See the classes, modelBinder logic and error below: public class Equipment { [Key] public int EquipmentId { get; set; } public virtual List<ChildRecord> Parents { get; set; } public virtual List<ChildRecord> Children { get; set; } } public class ChildRecord { [Key] public int ChildId { get; set; } [Required] public int Quantity { get; set; } [Required] public Equipment Parent { get; set; } [Required] public Equipment Child { get; set; } } I've tried building the mappings in both directions, though I only keep one set in at a time: modelBuilder.Entity<ChildRecord>() .HasRequired(x => x.Parent) .WithMany(x => x.Children ) .WillCascadeOnDelete(false); modelBuilder.Entity<ChildRecord>() .HasRequired(x => x.Child) .WithMany(x => x.Parents) .WillCascadeOnDelete(false); OR modelBuilder.Entity<Equipment>() .HasMany(x => x.Parents) .WithRequired(x => x.Child) .WillCascadeOnDelete(false); modelBuilder.Entity<Equipment>() .HasMany(x => x.Children) .WithRequired(x => x.Parent) .WillCascadeOnDelete(false); Regardless of which set I use, I get the error: The foreign key component 'Child' is not a declared property on type 'ChildRecord'. Verify that it has not been explicitly excluded from the model and that it is a valid primitive property. when I try do deploy my ef model to the database. If I build it without the modelBinder logic in place then I get two ID columns for Child and two ID columns for Parent in my ChildRecord table. This makes sense since it tries to auto create the navigation properties from Equipment and doesn't know that there are already properties in ChildRecord to fulfill this need. I tried using Data Annotations on the class, and no modelBuilder code, this failed with the same error as above: [Required] [ForeignKey("EquipmentId")] public Equipment Parent { get; set; } [Required] [ForeignKey("EquipmentId")] public Equipment Child { get; set; } AND [InverseProperty("Child")] public virtual List<ChildRecord> Parents { get; set; } [InverseProperty("Parent")] public virtual List<ChildRecord> Children { get; set; } I've looked at various other answers around the internet/SO, and the common difference seems to be that I am self joining where as all the answers I can find are for two different types. Entity Framework Code First Many to Many Setup For Existing Tables Many to many relationship with junction table in Entity Framework? Creating many to many junction table in Entity Framework

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  • Synchronous communication using NSOperationQueue

    - by chip_munks
    I am new to Objective C programming. I have created two threads called add and display using the NSInvocationOperation and added it on to the NSOperationQueue. I make the display thread to run first and then run the add thread. The display thread after printing the "Welcome to display" has to wait for the results to print from the add method. So i have set the waitUntilFinished method. Both the Operations are on the same queue. If i use waitUntilFinished for operations on the same queue there may be a situation for deadlock to happen(from apples developer documentation). Is it so? To wait for particular time interval there is a method called waitUntilDate: But if i need to like this wait(min(100,dmax)); let dmax = 20; How to do i wait for these conditions? It would be much helpful if anyone can explain with an example. EDITED: threadss.h ------------ #import <Foundation/Foundation.h> @interface threadss : NSObject { BOOL m_bRunThread; int a,b,c; NSOperationQueue* queue; NSInvocationOperation* operation; NSInvocationOperation* operation1; NSConditionLock* theConditionLock; } -(void)Thread; -(void)add; -(void)display; @end threadss.m ------------ #import "threadss.h" @implementation threadss -(id)init { if (self = [super init]) { queue = [[NSOperationQueue alloc]init]; operation = [[NSInvocationOperation alloc]initWithTarget:self selector:@selector(display) object:nil]; operation1 = [[NSInvocationOperation alloc]initWithTarget:self selector:@selector(add) object:nil]; theConditionLock = [[NSConditionLock alloc]init]; } return self; } -(void)Thread { m_bRunThread = YES; //[operation addDependency:operation1]; if (m_bRunThread) { [queue addOperation:operation]; } //[operation addDependency:operation1]; [queue addOperation:operation1]; //[self performSelectorOnMainThread:@selector(display) withObject:nil waitUntilDone:YES]; //NSLog(@"I'm going to do the asynchronous communication btwn the threads!!"); //[self add]; //[operation addDependency:self]; sleep(1); [queue release]; [operation release]; //[operation1 release]; } -(void)add { NSLog(@"Going to add a and b!!"); a=1; b=2; c = a + b; NSLog(@"Finished adding!!"); } -(void)display { NSLog(@"Into the display method"); [operation1 waitUntilFinished]; NSLog(@"The Result is:%d",c); } @end main.m ------- #import <Foundation/Foundation.h> #import "threadss.h" int main (int argc, const char * argv[]) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; threadss* thread = [[threadss alloc]init]; [thread Thread]; [pool drain]; return 0; } This is what i have tried with a sample program. output 2011-06-03 19:40:47.898 threads_NSOperationQueue[3812:1503] Going to add a and b!! 2011-06-03 19:40:47.898 threads_NSOperationQueue[3812:1303] Into the display method 2011-06-03 19:40:47.902 threads_NSOperationQueue[3812:1503] Finished adding!! 2011-06-03 19:40:47.904 threads_NSOperationQueue[3812:1303] The Result is:3 Is the way of invoking the thread is correct. 1.Will there be any deadlock condition? 2.How to do wait(min(100,dmax)) where dmax = 50.

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  • Need help in creating test application in Java and passing parameters into a new designed Java API.

    - by Christophe
    Need help, Please!!! By following the protocol, the Request should be built in 5 byte length, including 1 byte for changing Braud rate (Speed), and send request to a RS-232 port. Protocol: Request for the command processing, with optional extra byte for changing Baud Rate: LGT : length message ( LGT = 5 ) TYPE : 0x06 TO(time out): 0x0000 CMD : (1 byte) 0x02 application update Baud Rate : (1 byte) 0xNN (optional parameter to change baud rate of the Mnt App) where NN can be: 0x00 = No Baud Rate Change (similar to 4-byte command above) 0x09 = Change to 9600 Baud for Application Update speed 0x0A = Change to 19200 Baud for Application Update speed 0x0E = Change to 115200 Baud for Application Update speed All other bytes are not accepted and will result in a status of 0x01. I'm trying to test if my code works or not by creating another class (TestApplication.java) and pass the "3 differenr Baut rate" to this CPXAppliaction. the 3 Baud Rate is supposed to input by reading a file.txt. Question: How do you think these code (first half)? please don't warry about the details about the "sending part". I mean, do I need setter/getter for the "speed" parameter pass? I created the demo test class DemoApp.java (input speed by reading a txt file, and pass into CPXAppliaction). how do you think about that code? Many thanks to you guys!! public class CPXApplication extends CPXCommand { private int speed; . public CPXApplication() { speed = 9600; } public CPXApplication(int speedinit) { speed = speedinit; // TODO: where to get the speed? } protected void buildRequest() throws ElitePortException { String trans = ""; // build the full-qualified message following the protocol trans = addToRequest(trans, (char) 0); trans = addToRequest(trans, (char) 5); trans = addToRequest(trans, (char) 6); trans = addToRequest(trans, (char) 0); trans = addToRequest(trans, (char) 0); trans = addToRequest(trans, (char) 2); switch (speed) { case 9600: trans = addToRequest(trans, (char) 0x09); break; case 19200: trans = addToRequest(trans, (char) 0x0A); break; case 115200: trans = addToRequest(trans, (char) 0x0E); break; default: // TODO: unexpected baud rate. throw(); break; } trans = EncryptBinary(trans); trans = "F0." + trans; wrapRequest(trans); } protected String addToRequest(String req, char c) { return req + c; } protected String addToRequest(String req, String s) { return req + s; } protected String addToRequest(String req) { return req; } public void analyzeResponse() { //.............. } } Here is the demo test code: class Run { public static void run() { CPXAppliaction input = new CpXApplication(); int lineno = 0; try { FileReader fr = new FileReader("baudRateSpeed.txt"); BufferedReader reader = new BufferedReader(fr); String line = reader.readLine(); Scanner scan = null; while (line != null) { scan = new Scanner(line); String speed; speed = scan.next(); if (lineno == 0) { input.speed = speed; lineno++; } else { input = cpxapplication(speed, input); } line = reader.readLine(); } reader.close(); } catch (FileNotFoundException e) { System.out.println("Could not find the file"); } catch (IOException e) { System.out.println("Had a problem reading from file"); } } } public class DemoApp{ public void main(String args[]) { run(); }

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  • Keeping video viewing statistics breakdown by video time in a database

    - by Septagram
    I need to keep a number of statistics about the videos being watched, and one of them is what parts of the video are being watched most. The design I came up with is to split the video into 256 intervals and keep the floating-point number of views for each of them. I receive the data as a number of intervals the user watched continuously. The problem is how to store them. There are two solutions I see. Row per every video segment Let's have a database table like this: CREATE TABLE `video_heatmap` ( `id` int(11) NOT NULL AUTO_INCREMENT, `video_id` int(11) NOT NULL, `position` tinyint(3) unsigned NOT NULL, `views` float NOT NULL, PRIMARY KEY (`id`), UNIQUE KEY `idx_lookup` (`video_id`,`position`) ) ENGINE=MyISAM Then, whenever we have to process a number of views, make sure there are the respective database rows and add appropriate values to the views column. I found out it's a lot faster if the existence of rows is taken care of first (SELECT COUNT(*) of rows for a given video and INSERT IGNORE if they are lacking), and then a number of update queries is used like this: UPDATE video_heatmap SET views = views + ? WHERE video_id = ? AND position >= ? AND position < ? This seems, however, a little bloated. The other solution I came up with is Row per video, update in transactions A table will look (sort of) like this: CREATE TABLE video ( id INT NOT NULL AUTO_INCREMENT, heatmap BINARY (4 * 256) NOT NULL, ... ) ENGINE=InnoDB Then, upon every time a view needs to be stored, it will be done in a transaction with consistent snapshot, in a sequence like this: If the video doesn't exist in the database, it is created. A row is retrieved, heatmap, an array of floats stored in the binary form, is converted into a form more friendly for processing (in PHP). Values in the array are increased appropriately and the array is converted back. Row is changed via UPDATE query. So far the advantages can be summed up like this: First approach Stores data as floats, not as some magical binary array. Doesn't require transaction support, so doesn't require InnoDB, and we're using MyISAM for everything at the moment, so there won't be any need to mix storage engines. (only applies in my specific situation) Doesn't require a transaction WITH CONSISTENT SNAPSHOT. I don't know what are the performance penalties of those. I already implemented it and it works. (only applies in my specific situation) Second approach Is using a lot less storage space (the first approach is storing video ID 256 times and stores position for every segment of the video, not to mention primary key). Should scale better, because of InnoDB's per-row locking as opposed to MyISAM's table locking. Might generally work faster because there are a lot less requests being made. Easier to implement in code (although the other one is already implemented). So, what should I do? If it wasn't for the rest of our system using MyISAM consistently, I'd go with the second approach, but currently I'm leaning to the first one. But maybe there are some reasons to favour one approach or another?

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