Search Results

Search found 33297 results on 1332 pages for 'java java ee'.

Page 291/1332 | < Previous Page | 287 288 289 290 291 292 293 294 295 296 297 298  | Next Page >

  • Mix of Arabic and English causes problems in JTextArea (Java)

    - by Dan
    I have a JTextArea which displays HTML of an Arabic web page. So it's essentially a mix of English and Arabic. In the JTextArea, with columns set to 30, certain text just disappears instead of wrapping properly. The weird thing is that if I copy the invisible text and paste it into Notepad, then I can see it in Notepad. If I change the number of columns to 40, everything displays fine. Any ideas?

    Read the article

  • Stateful Iterators Java

    - by Gitmo
    What is a Stateful Iterator? This question relates to an Iterator defined in Hadoop for performing Joins. As the reference documentation states: This defines an interface to a stateful Iterator that can replay elements added to it directly. Note that this does not extend Iterator. What does 'replay elements added to it directly' mean? How is this iterator different from a usual iterator?

    Read the article

  • Java Inheritance - Getting a Parameter from Parent Class

    - by Aaron
    I'm trying to take one parameter from the parent class of Car and add it to my array (carsParked), how can i do this? Parent Class public class Car { protected String regNo; //Car registration number protected String owner; //Name of the owner protected String carColor; /** Creates a Car object * @param rNo - registration number * @param own - name of the owner **/ public Car (String rNo, String own, String carColour) { regNo = rNo; owner = own; carColor = carColour; } /** @return The car registration number **/ public String getRegNo() { return regNo; } /** @return A String representation of the car details **/ public String getAsString() { return "Car: " + regNo + "\nColor: " + carColor; } public String getColor() { return carColor; } } Child Class public class Carpark extends Car { private String location; // Location of the Car Park private int capacity; // Capacity of the Car Park - how many cars it can hold private int carsIn; // Number of cars currently in the Car Park private String[] carsParked; /** Constructor for Carparks * @param loc - the Location of the Carpark * @param cap - the Capacity of the Carpark */ public Carpark (String locations, int room) { location = locations; capacity = room; } /** Records entry of a car into the car park */ public void driveIn() { carsIn = carsIn + 1; } /** Records the departure of a car from the car park */ public void driveOut() { carsIn = carsIn - 1; } /** Returns a String representation of information about the carpark */ public String getAsString() { return location + "\nCapacity: " + capacity + " Currently parked: " + carsIn + "\n*************************\n"; } }

    Read the article

  • Writing to an already existing file using FileWriter Java

    - by delo
    Is there anyway I can write to an already existing file using Filewriter For example when the user clicks a submit button: FileWriter writer = new FileWriter("myfile.csv"); writer.append("LastName"); writer.append(','); writer.append("FirstName"); writer.append('/n'); writer.append(LastNameTextField.getText()); writer.append(','); writer.append(FirstNameTextField.getText()); I want to be able to write new data into the already existing myfile.csv without having to recreate a brand new one every time

    Read the article

  • java - unwanted object overwriting

    - by gosling
    Hello everyone! I'm trying to make a program that solves the logic wheels puzzle. I construct the root node and I try to produce the different child-nodes that are produced by making different moves of the wheels. The problem is that while I try to produce the children, the root node is overwrited,and everything is messed-up and I really don't know why. Here you can find the puzzle logic wheels. I represent the wheels as 3x3 arrays. Here is the code that implements the moves: public Node turn_right(Node aNode, int which_wheel) { Node newNode = new Node(aNode.getYellow_wheel(),aNode.getBlue_wheel(),aNode.getGreen_wheel()); int[][] yellow = new int[3][3]; int[][] blue = new int[3][3]; int[][] green = new int[3][3]; if(which_wheel==0) //turn yellow wheel of this node to right { yellow[1][0] = newNode.getYellow_wheel()[0][0]; yellow[2][0] = newNode.getYellow_wheel()[1][0]; yellow[2][1] = newNode.getYellow_wheel()[2][0]; yellow[2][2] = newNode.getYellow_wheel()[2][1]; yellow[1][2] = newNode.getYellow_wheel()[2][2]; yellow[0][2] = newNode.getYellow_wheel()[1][2]; yellow[0][1] = newNode.getYellow_wheel()[0][2]; yellow[0][0] = newNode.getYellow_wheel()[0][1]; blue = newNode.getBlue_wheel(); blue[1][0] = newNode.getYellow_wheel()[1][2]; blue[2][0] = newNode.getYellow_wheel()[2][2]; green = newNode.getGreen_wheel(); } else if(which_wheel == 1)// turn blue wheel of this node to right { blue[1][0] = newNode.getBlue_wheel()[0][0]; blue[2][0] = newNode.getBlue_wheel()[1][0]; blue[2][1] = newNode.getBlue_wheel()[2][0]; blue[2][2] = newNode.getBlue_wheel()[2][1]; blue[1][2] = newNode.getBlue_wheel()[2][2]; blue[0][2] = newNode.getBlue_wheel()[1][2]; blue[0][1] = newNode.getBlue_wheel()[0][2]; blue[0][0] = newNode.getBlue_wheel()[0][1]; yellow = newNode.getYellow_wheel(); yellow[0][2] = newNode.getBlue_wheel()[0][0]; yellow[1][2] = newNode.getBlue_wheel()[1][0]; green = newNode.getGreen_wheel(); green[1][0] = newNode.getBlue_wheel()[1][2]; green[2][0] = newNode.getBlue_wheel()[2][2]; } else if (which_wheel == 2)//turn green wheel of this node to right { green[0][0] = newNode.getGreen_wheel()[0][1]; green[0][1] = newNode.getGreen_wheel()[0][2]; green[0][2] = newNode.getGreen_wheel()[1][2]; green[1][2] = newNode.getGreen_wheel()[2][2]; green[2][2] = newNode.getGreen_wheel()[2][1]; green[2][1] = newNode.getGreen_wheel()[2][0]; green[2][0] = newNode.getGreen_wheel()[1][0]; green[1][0] = newNode.getGreen_wheel()[0][0]; yellow = newNode.getYellow_wheel(); blue = newNode.getBlue_wheel(); blue[0][2] = newNode.getGreen_wheel()[0][0]; blue[1][2] = newNode.getGreen_wheel()[1][0]; } newNode= new Node(yellow,blue,green); return newNode; } There is another function, like this one that does the oposite:it turns the wheels to left. My problem is that I do not want object's aNode tables to be overwritten. Thank you very much.

    Read the article

  • Java - Circular Garbage Collection

    - by aloh
    A <- B <- C <- D <- A... // A is firstNode, D is lastNode if ( length == 1 ) { firstNode = null; lastNode = null; firstNode.next = null; firstNode.prev = null; } else { Node secondNode = firstNode.next; Node secondToLast = lastNode.prev; firstNode.next = null; firstNode.prev = null; lastNode.next = null; lastNode.prev = null; secondNode.prev = null; secondToLast.next = null; firstNode = null; lastNode = null; } That should send everything in between as candidates for garbage collection, I hope?

    Read the article

  • Java Enum List from Class

    - by DD
    How do I go from a Class object to a list of enums generically? i.e. public static <T extends Enum> List<T> getList(Class<T> clazz) I cant find a way to get to the values() method

    Read the article

  • Java - Calling all methods of a class

    - by Thomas Eschemann
    I'm currently working on an application that has to render several Freemarker templates. So far I have a Generator class that handles the rendering. The class looks more or less like this: public class Generator { public static void generate(…) { renderTemplate1(); renderTemplate2(); renderTemplate3(); } private static void render(…) { // renders the template } private static void renderTemplate1() { // Create config object for the rendering // and calls render(); }; private static void renderTemplate1() { // Create config object for the rendering // and calls render(); }; … } This works, but it doesn't really feel right. What I would like to do is create a class that holds all the renderTemplate...() methods and then call them dynamically from my Generator class. This would make it cleaner and easier to extend. I was thinking about using something like reflection, but it doesn't really feel like a good solution either. Any idea on how to implement this properly ?

    Read the article

  • Simple java synchronization question

    - by Misha Koshelev
    I was wondering, which is correct: Option One class A { public void methodOne() { synchronized(this) { modifyvalue notifyAll() } } public void methodTwo() { while (valuenotmodified) { synchronized(this) { wait() } } } Option Two class A { public void methodOne() { modifyvalue synchronized(this) { notifyAll() } } public void methodTwo() { while (valuenotmodified) { synchronized(this) { wait() } } } and why?

    Read the article

  • Insert code into a method - Java

    - by DutrowLLC
    Is there a way to automatically insert code into a method? I have the following and I would like to insert the indicated code: public class Person { Set<String> updatedFields = new LinkedHashSet<String>(); String firstName; public String getFirstName(){ return firstName; } boolean isFirstNameChanged = false; // Insert public void setFirstName(String firstName){ if( !isFirstNameChanged ){ // Insert isFirstNameChanged = true; // Insert updatedFields.add("firstName"); // Insert } // Insert this.firstName = firstName; } } I'm also not sure if I can the subset of the method name as a string from inside the method itself as indicated on the line where I add the fieldName as a string into the set of updated fields: updatedFields.add("firstName");. And I'm not sure how to insert fields into a class where I add the boolean field that tracks if the field has been modified or not before (for efficiency to prevent having to manipulate the Set): boolean isFirstNameChanged = false; It seems to most obvious answer to this would be to use code templates inside eclipse, but I'm concerned about having to go back and change the code later.

    Read the article

  • Lines don't overlap when they should Java Swing

    - by Sven
    I'm drawing lines in a JFrame on a self made gridPanel. Problem is, I draw the lines between 2 points. When I have a line that is between point 1 and point 2 and a line between point 2 and point 3, the lines should connect. This however isn,t the case, there is a small gap in between, no idea why. But it isn't drawing till the end of the specified point. (start point is correct.) Here is the code of the JFrame: public void initialize(){ this.setLayout(new BorderLayout()); this.setPreferredSize(new Dimension(500, 400)); gridPane = new GridPane(); gridPane.setBackground(Color.WHITE); gridPane.setSize(this.getPreferredSize()); gridPane.setLocation(0, 0); this.add(gridPane,BorderLayout.CENTER); //createSampleLabyrinth(); drawWall(0,5,40,5); //These are the 2 lines that don't connect. drawWall(40,5,80,5); this.pack(); } drawWall calls a method that calls a method in GridPane. The relevant code in gridPane: /** * Draws a wall on this pane. With the starting point being x1, y1 and its end x2,y2. * @param x1 * @param y1 * @param x2 * @param y2 */ public void drawWall(int x1, int y1, int x2, int y2) { Wall wall = new Wall(x1,y1,x2,y2, true); wall.drawGraphic(); wall.setLocation(x1, y1); wall.setSize(10000,10000); this.add(wall, JLayeredPane.DEFAULT_LAYER); this.repaint(); } This method creates a wall and puts it in the Jframe. The relevant code of the wall: public class Wall extends JPanel { private int x1; private int x2; private int y1; private int y2; private boolean black; /** * x1,y1 is the start point of the wall (line) end is x2,y2 * * @param x1 * @param y1 * @param x2 * @param y2 */ public Wall(int x1, int y1, int x2, int y2, boolean black) { this.x1 = x1; this.x2 = x2; this.y1 = y1; this.y2 = y2; this.black = black; setOpaque(false); } private static final long serialVersionUID = 1L; public void drawGraphic() { repaint(); } public void paintComponent(Graphics g) { super.paintComponent(g); Graphics2D g2 = (Graphics2D) g; if(black){ g2.setColor(Color.BLACK); g2.setStroke(new BasicStroke(8)); } else { g2.setColor(Color.YELLOW); g2.setStroke(new BasicStroke(3)); } g2.drawLine(x1, y1, x2, y2); } } So, where am I going wrong? The true/false is to determine if the wall should be black or yellow, nothing to be concerned about.

    Read the article

  • Sudoku Recursion Issue (Java)

    - by SkylineAddict
    I'm having an issue with creating a random Sudoku grid. I tried modifying a recursive pattern that I used to solve the puzzle. The puzzle itself is a two dimensional integer array. This is what I have (By the way, the method doesn't only randomize the first row. I had an idea to randomize the first row, then just decided to do the whole grid): public boolean randomizeFirstRow(int row, int col){ Random rGen = new Random(); if(row == 9){ return true; } else{ boolean res; for(int ndx = rGen.nextInt() + 1; ndx <= 9;){ //Input values into the boxes sGrid[row][col] = ndx; //Then test to see if the value is valid if(this.isRowValid(row, sGrid) && this.isColumnValid(col, sGrid) && this.isQuadrantValid(row, col, sGrid)){ // grid valid, move to the next cell if(col + 1 < 9){ res = randomizeFirstRow(row, col+1); } else{ res = randomizeFirstRow( row+1, 0); } //If the value inputed is valid, restart loop if(res == true){ return true; } } } } //If no value can be put in, set value to 0 to prevent program counting to 9 setGridValue(row, col, 0); //Return to previous method in stack return false; } This results in an ArrayIndexOutOfBoundsException with a ridiculously high or low number (+- 100,000). I've tried to see how far it goes into the method, and it never goes beyond this line: if(this.isRowValid(row, sGrid) && this.isColumnValid(col, sGrid) && this.isQuadrantValid(row, col, sGrid)) I don't understand how the array index goes so high. Can anyone help me out?

    Read the article

  • JAVA: Build XML document using XPath expressions

    - by snoe
    I know this isn't really what XPath is for but if I have a HashMap of XPath expressions to values how would I go about building an XML document. I've found dom-4j's DocumentHelper.makeElement(branch, xpath) except it is incapable of creating attributes or indexing. Surely a library exists that can do this? Map xMap = new HashMap(); xMap.put("root/entity/@att", "fooattrib"); xMap.put("root/array[0]/ele/@att", "barattrib"); xMap.put("root/array[0]/ele", "barelement"); xMap.put("root/array[1]/ele", "zoobelement"); would result in: <root> <entity att="fooattrib"/> <array><ele att="barattrib">barelement</ele></array> <array><ele>zoobelement</ele></array> </root>

    Read the article

  • Using interfaces in java..Newb question

    - by Rahul
    Suppose there in an interface Displaceable and a class Circle which implements Displaceable. Displaceable has a method named move() which of course is implemented in Circle. What would happen in the following scenario? Circle a = new Circle(..); Displaceable b = a; b.move() Would the object refer to the Circle's move method?

    Read the article

  • Sending files from server to client in Java

    - by Lee Jacobson
    Hi, I'm trying to find a way to send files of different file types from a server to a client. I have this code on the server to put the file into a byte array: File file = new File(resourceLocation); byte[] b = new byte[(int) file.length()]; FileInputStream fileInputStream; try { fileInputStream = new FileInputStream(file); try { fileInputStream.read(b); } catch (IOException ex) { System.out.println("Error, Can't read from file"); } for (int i = 0; i < b.length; i++) { fileData += (char)b[i]; } } catch (FileNotFoundException e) { System.out.println("Error, File Not Found."); } I then send fileData as a string to the client. This works fine for txt files but when it comes to images I find that although it creates the file fine with the data in, the image won't open. I'm not sure if I'm even going about this the right way. Thanks for the help.

    Read the article

  • Java Runtime.freeMemory() returning bizarre results when adding more objects

    - by Sotirios Delimanolis
    For whatever reason, I wanted to see how many objects I could create and populate a LinkedList with. I used Runtime.getRuntime().freeMemory() to get the approximation of free memory in my JVM. I wrote this: public static void main(String[] arg) { Scanner kb = new Scanner(System.in); List<Long> mem = new LinkedList<Long>(); while (true) { System.out.println("Max memory: " + Runtime.getRuntime().maxMemory() + ". Available memory: " + Runtime.getRuntime().freeMemory() + " bytes. Press enter to use more."); String s = kb.nextLine(); if (s.equals("m")) for (int i = 0; i < 1000000; i++) { mem.add(new Long((new Random()).nextLong())); } } } If I write in m, the app adds a million Long objects to the list. You would think the more objects (to which we have references, so can't be gc'ed), the less free memory. Running the code: Max memory: 1897725952. Available memory: 127257696 bytes. m Max memory: 1897725952. Available memory: 108426520 bytes. m Max memory: 1897725952. Available memory: 139873296 bytes. m Max memory: 1897725952. Available memory: 210632232 bytes. m Max memory: 1897725952. Available memory: 137268792 bytes. m Max memory: 1897725952. Available memory: 239504784 bytes. m Max memory: 1897725952. Available memory: 169507792 bytes. m Max memory: 1897725952. Available memory: 259686128 bytes. m Max memory: 1897725952. Available memory: 189293488 bytes. m Max memory: 1897725952. Available memory: 387686544 bytes. The available memory fluctuates. How does this happen? Is the GC cleaning up other things (what other things are there on the heap to really clean up?), is the freeMemory() method returning an approximation that's way off? Am I missing something or am I crazy?

    Read the article

  • Class unloading in java

    - by java_geek
    When a classloader is garbage collected, are the classes loaded by it unloaded? When the JVM is running is verbose mode, all the loaded classes are o/p. Similarly will the JVM log when it unloads a class? I wrote a custom class loader to test this, but could not see any verbose log for unloading of the classes. CustomClassLoader loader = new CustomClassLoader(new URL[]{}, CustomClassLoader.class.getClassLoader()); loader.addURL("D:\workspace\ClassLoaderTest\implementation.jar"); Class c = null; try { c = Class.forName("Horse",false,loader); if (c != null) { try { Animal animal = (Animal)c.newInstance(); animal.eat(); } catch(Exception ex) { ex.printStackTrace(); } } } catch(Exception e) { e.printStackTrace(); } loader = null; byte[] b = new byte[58*1024*1024]; System.gc(); ClassLoadingMXBean clBean = ManagementFactory.getClassLoadingMXBean(); System.out.println("Number of classes currently loaded " + clBean.getLoadedClassCount()); System.out.println("Number of classes loaded totally " + clBean.getTotalLoadedClassCount()); System.out.println("Number of classes unloaded " + clBean.getUnloadedClassCount()); Even the ClassLoadingMXBean gives number of unloaded classes as 0. How can i know that a class is unloaded when the class loader is GCed?

    Read the article

  • Regex help -- cleaning up whitespace -- Java

    - by FarmBoy
    I'm trying to view the text of HTML files in a reasonable way. After I remove all of the markup and retain only the visible text, I obtain a String that looks something like this: \n\n\n\n \n\n\n \n\n \n Title here \n\n\n \n\n \n\n Menu Item 1 \n\n \n\n Menu Item 2 \n\n\n \n\n you get the point. I would like to use String.replaceAll(String regex, String regex) to replace any whitespace substring that contains more than two occurances of \n with "\n\n". Any ideas?

    Read the article

  • Duplicates in a sorted java array

    - by Max Frazier
    I have to write a method that takes an array of ints that is already sorted in numerical order then remove all the duplicate numbers and return an array of just the numbers that have no duplicates. That array must then be printed out so I can't have any null pointer exceptions. The method has to be in O(n) time, can't use vectors or hashes. This is what I have so far but it only has the first couple numbers in order without duplicates and then just puts the duplicates in the back of the array. I can't create a temporary array because it gives me null pointer exceptions. public static int[] noDups(int[] myArray) { int j = 0; for (int i = 1; i < myArray.length; i++) { if (myArray[i] != myArray[j]) { j++; myArray[j] = myArray[i]; } } return myArray; }

    Read the article

  • 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(); }}

    Read the article

< Previous Page | 287 288 289 290 291 292 293 294 295 296 297 298  | Next Page >