Problem with mouselistener

First , I defined a mouselistener like
jButton2.addMouseListener(new MouseAdapter()
        public void mousePressed(MouseEvent e)
          jButton2_mousePressed(e);
      });but when I use this code
private void jButton2_mousePressed(MouseEvent e) throws IOException
    setFiles();
    compress();
}then it compiles with an error says
Error(74,32): unreported exception: java.io.IOException; must be caught or declared to be thrownwhere line 47 contains
public void mousePressed(MouseEvent e)Note : I have to add "throws IOException" because I deal with files in those functions.
Is there any solution?

and you need to start using actions:
http://java.sun.com/docs/books/tutorial/uiswing/misc/action.html

Similar Messages

Problem with MouseListener.... please help

Hi, I'm having trouble with my code, I don't know why it isn't executing the Mouse Events, I have a class (name of class: ImageArea) that extends JPanel and implements MouseListener, and my mouseClicked method prints (or its supposed to) the cursor coordinates, but nothing happens when I clicked.
Now, I have another class (name of class: gameGUI) that extends JFrame and this class contains ImageArea. The idea is to print the coordinates when the mouse is clicked in the area of ImageArea.
//HERE'S THE CODE OF ImageArea
import java.lang.*;
import java.util.*;
import java.io.*;
import java.text.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.awt.image.BufferedImage;
class ImageArea extends JPanel implements MouseListener {
 //SE DEFINEN VARIABLES GLOBALES
 private int SizeX, SizeY, CoordX, CoordY, NumPixel, CantImages, PromedioX, PromedioY, LayX, LayY, VarMay, VarMen;
 private BufferedImage Imagen;
 private BufferedReader Archivo;
 //private pideDatos datos;
 private ArrayList AlDatos, AlCoordY, AlCoordX;
 //para el manejo del archivo xpm (clase propia)
 //private xpmConverter XPM; // MY class
 //CONSTRUCTOR
 public ImageArea() {
 setPreferredSize(new Dimension(600, 550));
setBackground(Color.black);
 public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
 g2.drawImage(Imagen, null, CoordX, CoordY);
public void mouseClicked (MouseEvent me) {
 CoordX = me.getX();
 CoordY = me.getY();
 System.out.println("CoordX = " + CoordX + " CoordY = " + CoordY);
// System.out.println(AlCoordX);
// System.out.println(AlCoordY);
 //ESCUCHADORES DEL MOUSE QUE NO SE UTILIZAN
 public void mouseExited(MouseEvent e) {}
 public void mouseMoved(MouseEvent e) {}
public void mouseEntered(MouseEvent e) {}
public void mousePressed(MouseEvent e) {}
public void mouseDragged(MouseEvent e) {}
public void mouseReleased(MouseEvent e) {}
//Here's the code of gameGUI
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.filechooser.*;
import java.lang.*;
import java.util.*;
import java.io.*;
import java.text.*;
public class gameGUI extends JFrame
 private JTextField NumImageText;
 private JList ImageList;
 private JScrollPane ImageScroll;
 private JSeparator jSeparator1;
 private JButton PrevButton, NextButton, AcceptButton, CargarButton, ResolverButton, SalirButton;
 private JPanel OptionPanel;
 private Container Contenedor;
 private ImageArea CampoImagen;
// private xpmConverter Imagen; //My class
 public gameGUI() {
 NumImageText = new JTextField();
 ImageList = new JList();
 ImageScroll = new JScrollPane();
 jSeparator1 = new JSeparator();
 PrevButton = new JButton();
 NextButton = new JButton();
 AcceptButton = new JButton();
 CargarButton = new JButton();
 ResolverButton = new JButton();
 SalirButton = new JButton();
 OptionPanel = new JPanel();
 Contenedor = this.getContentPane();
 CampoImagen = new ImageArea();
 // numImageText
 NumImageText.setText("10");
 // imageList
 ImageList.addListSelectionListener(new ListSelectionListener() {
 public void valueChanged(ListSelectionEvent e) {
 jList1_valueChanged(e);
 // jScrollPane1
 ImageScroll.setViewportView(ImageList);
 ImageScroll.setPreferredSize(new Dimension(220, 550));
 // prevButton
 PrevButton.setText("<< Anteriores");
 PrevButton.setSize(20, 25);
 PrevButton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e) {
 prevButton_actionPerformed(e);
 // nextButton
 NextButton.setText("Siguientes >>");
 NextButton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e) {
 nextButton_actionPerformed(e);
 // acceptButton
 AcceptButton.setText("Aceptar");
 AcceptButton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e) {
 acceptButton_actionPerformed(e);
 // cargarButton
 CargarButton.setText("Cargar Imagen");
 CargarButton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e) {
 cargarButton_actionPerformed(e);
 // resolverButton
 ResolverButton.setText("Resolver");
 ResolverButton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e) {
 resolverButton_actionPerformed(e);
 // salirButton
 SalirButton.setText("Salir");
 SalirButton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e) {
 salirButton_actionPerformed(e);
 OptionPanel.setLayout(new GridLayout(1, 7));
 OptionPanel.add(PrevButton);
 OptionPanel.add(NextButton);
 OptionPanel.add(NumImageText);
 OptionPanel.add(AcceptButton);
 OptionPanel.add(CargarButton);
 OptionPanel.add(ResolverButton);
 OptionPanel.add(SalirButton);
 Contenedor.setLayout(new BorderLayout());
 Contenedor.add(OptionPanel, BorderLayout.NORTH);
 Contenedor.add(ImageScroll, BorderLayout.WEST);
 Contenedor.add(CampoImagen, BorderLayout.CENTER);
 this.setTitle("RompeCabezas");
 this.setLocation(new Point(200, 0));
 this.setSize(new Dimension(800, 600));
 this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
 private void jList1_valueChanged(ListSelectionEvent e) {
 System.out.println("\njList1_valueChanged(ListSelectionEvent e) called.");
 if(!e.getValueIsAdjusting()) {
 Object o = ImageList.getSelectedValue();
 System.out.println(">>" + ((o==null)? "null" : o.toString()) + " is selected.");
 private void prevButton_actionPerformed(ActionEvent e) {
 System.out.println("\nprevButton_actionPerformed(ActionEvent e) called.");
 private void nextButton_actionPerformed(ActionEvent e) {
 System.out.println("\nnextButton_actionPerformed(ActionEvent e) called.");
 private void acceptButton_actionPerformed(ActionEvent e) {
 System.out.println("\nacceptButton_actionPerformed(ActionEvent e) called.");
 private void cargarButton_actionPerformed(ActionEvent e) {
 String dir = null, filePath;
 File dir1;
 JFileChooser openFile;
 int returnVal;
 try {
 dir1 = new File (".");
 dir = dir1.getCanonicalPath();
 catch(Exception ex) {
 System.out.println("error abriendo el path actual: " + dir);
 if (dir == null) {
 openFile = new JFileChooser();
 else {
 openFile = new JFileChooser(dir);
 openFile.setLocation(new Point(0, 100));
 returnVal = openFile.showOpenDialog(this);
 if(returnVal == JFileChooser.APPROVE_OPTION){
 filePath = openFile.getSelectedFile().getAbsolutePath();
 if(filePath.endsWith(".xpm")) {
 Imagen = new xpmConverter(filePath);
 System.out.print("\nCargando imagen... ");
// CampoImagen.setFilePath(filePath);
// CampoImagen.paintBufImage();
// CampoImagen.repaint();
// Imagen.setAlCoordX(CampoImagen.getAlCoordX());
// Imagen.setAlCoordY(CampoImagen.getAlCoordY());
 //Imagen.setNumImagenesX(CampoImagen.getNumImagenesX());
// Imagen.createSubImages();
 else {
 System.out.println("No es de tipo xpm");
 System.out.println("Listo!");
 private void resolverButton_actionPerformed(ActionEvent e) {
 /* BTree prueba = new BTree("prueba", 3, 3);
 xpmConverter xprueba = new xpmConverter("sapri2.xpm");
 String a = xprueba.createSubImage(0, 0, 33, 25);
 String b = xprueba.createSubImage(34, 0, 65, 29);
 String c = xprueba.createSubImage(66, 0, 81, 31);
 prueba.insert("Imagen01", a);
 prueba.insert("Imagen02", b);
 prueba.insert("Imagen03", c);
 System.out.println("x1 0, x2 33, y1 0, y2 25");
 System.out.println(prueba.search("Imagen01"));
 System.out.println("x1 34, x2 65, y1 0, y2 29");
 System.out.println(prueba.search("Imagen02"));
 System.out.println("x1 66, x2 81, y1 0, y2 31");
 System.out.println(prueba.search("Imagen03"));
 private void salirButton_actionPerformed(ActionEvent e) {
 System.exit(0);
 //MAIN
 public static void main(String[] args)
 JFrame.setDefaultLookAndFeelDecorated(true);
 JDialog.setDefaultLookAndFeelDecorated(true);
 try
 UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
 catch (Exception ex)
 System.out.println("Failed loading L&F: ");
 System.out.println(ex);
 gameGUI TheGame = new gameGUI();
 TheGame.setVisible(true);
}

Hi, I'm having trouble with my code, I don't know why
it isn't executing the Mouse Events, I have a class
(name of class: ImageArea) that extends JPanel and
implements MouseListener, and my mouseClicked method
prints (or its supposed to) the cursor coordinates,
but nothing happens when I clicked. Because you never added your object as a mouse listener to any other object.
In the constructor you need something like:
addMouseListener(this);

Problem with ScrollPane and JFrame Size

Hi,
The code is workin but after change the size of frame it works CORRECTLY.Please help me why this frame is small an scrollpane doesn't show at the beginning.
Here is the code:
import java.awt.*;
public class canvasExp extends Canvas
     private static final long serialVersionUID = 1L;
     ImageLoader map=new ImageLoader();
    Image img = map.GetImg();
    int h, w;               // the height and width of this canvas
     public void update(Graphics g)
        paint(g);
    public void paint(Graphics g)
            if(img != null)
                 h = getSize().height;
                 System.out.println("h:"+h);
                  w = getSize().width;
                  System.out.println("w:"+w);
                  g.drawRect(0,0, w-1, h-1);     // Draw border
              // System.out.println("Size= "+this.getSize());
                 g.drawImage(img, 0,0,this.getWidth(),this.getHeight(), this);
                int width = img.getWidth(this);
                //System.out.println("W: "+width);
                int height = img.getHeight(this);
                //System.out.println("H: "+height);
                if(width != -1 && width != getWidth())
                    setSize(width, getHeight());
                if(height != -1 && height != getHeight())
                    setSize(getWidth(), height);
}I create frame here...
import java.awt.*;
import java.awt.event.*;
import javax.swing.JFrame;
public class frame extends JFrame implements MouseMotionListener,MouseListener
     private static final long serialVersionUID = 1L;
    private ScrollPane scrollPane;
    private int dragStartX;
    private int dragStartY;
    private int lastX;
    private int lastY;
    int cordX;
    int cordY;
    canvasExp canvas;
    public frame()
        super("test");
        canvas = new canvasExp();
        canvas.addMouseListener(this);
        canvas.addMouseMotionListener(this);
        scrollPane = new ScrollPane();
        scrollPane.setEnabled(true);
        scrollPane.add(canvas);
        add(scrollPane);
        setSize(300,300);
        pack();
        setVisible(true);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    public void mousePressed(MouseEvent e)
        dragStartX = e.getX();
        dragStartY = e.getY();
        lastX = getX();
        lastY = getY();
    public void mouseReleased(MouseEvent mouseevent)
    public void mouseClicked(MouseEvent e)
        cordX = e.getX();
        cordY = e.getY();
        System.out.println((new StringBuilder()).append(cordX).append(",").append(cordY).toString());
    public void mouseEntered(MouseEvent mouseevent)
    public void mouseExited(MouseEvent mouseevent)
    public void mouseMoved(MouseEvent mouseevent)
    public void mouseDragged(MouseEvent e)
        if(e.getX() != lastX || e.getY() != lastY)
            Point p = scrollPane.getScrollPosition();
            p.translate(dragStartX - e.getX(), dragStartY - e.getY());
            scrollPane.setScrollPosition(p);
}...and call here
public class main {
     public main(){}
     public static void main (String args[])
         frame f = new frame();
}There is something I couldn't see here.By the way ImageLoader is workin I get the image.
Thank you for your help,please answer me....

I'm not going to even attempt to resolve the problem posted. There are other problems with your code that should take priority.
-- class names by convention start with a capital letter.
-- don't use the name of a common class from the standard API for your custom class, not even with a difference of case. It'll come back to bite you.
-- don't mix awt and Swing components in the same GUI. Change your class that extends Canvas to extend JPanel instead, and override paintComponent(...) instead of paint(...).
-- launch your GUI on the EDT by wrapping it in a SwingUtilities.invokeLater or EventQueue.invokeLater.
-- calling setSize(...) followed by pack() is meaningless. Use one or the other.
-- That's not the correct way to display a component in a scroll pane.
Ah, well, and the problem is that when you call pack(), it retrieves the preferredSize of the components in the JFrame, and you haven't set a preferredSize for the scroll pane.
Please, for your own good, take a break from whatever it is you're working on and go through The Java™ Tutorials: [Creating a GUI with JFC/Swing|http://java.sun.com/docs/books/tutorial/uiswing/TOC.html]
db

Problem with setCursor for JButton in cell on JTable

i have a problem with setCursor to JButton that is in a cell of the JTable}
this is the code
public class JButtonCellRenderer extends JButton implements TableCellRenderer {
public JButtonCellRenderer() {
setOpaque(true);
public Component getTableCellRendererComponent(JTable table, Object value,
boolean isSelected, boolean hasFocus,
int row, int column) {
if (isSelected) {
setForeground(table.getSelectionForeground());
setBackground(table.getSelectionBackground());
else {
setForeground(table.getForeground());
setBackground(Color.WHITE);
setBorder(null);
if(table.getValueAt(row,column) == null){
setText("");
if(isSelected){
setBackground(table.getSelectionBackground());
}else{
setBackground(Color.WHITE);
}else{
if(table.getValueAt(row,column) instanceof JButton){
JButton _button = (JButton)table.getValueAt(row,column);
if(_button.getText().trim().equals("")){
setText("<html>"+ "Ver..."+"");
}else{
setText("<html>"+ "" + _button.getText() + ""+"");
return this;
}

Not quite sure I understand the problem, but I guess you have tried to call setCursor on your renderer and found it didn't work? The reason, I think, is that the renderer only renders a JButton. The thing that ends up in the table is in fact only a "picture" of a JButton, and among other things it won't receive and interact with any events, such as MouseEvents (so it wouldn't know that the cursor should change).
There are at least two alternatives for you: You can perhaps use a CellEditor instead of a CellRenderer. Or you can add a MouseListener to the table and then use the methods column/rowAtPoint to figure out if the cursor is over your JButton cell and change the cursor yourself if it is.

Problem with busy cursor

IHey there,
i have a popping up window in my Flex app. This window needs a little time to get created. In this time I want to set the Cursor to busy. But instead of the busy cursor Flex displays no cursor, also the arrow cursor disappears.
I tried the hack with callLater but it doesn't help. Had anyone a similar problem and knows how to fix it?
By the way: What is the best way to set the busy cursor? Static, with the parentApplication.cursoManager property or in the component with this.cursoManager? All of these ways have the same result on my problem: no cursor!
click on a item (own component, extended Canvas, buttonMode = true)
call function by MouseListener
function {
    this.cursorManager.setBusyCursor();
    this.callLater(doPopUpWork);
callLater function
doPopUpWork() {
    // DO WORK AND ADD POPUP
    this.cursorManager.removeBusyCursor;
I checked the right timing with trace statements [ trace("setBusy") ... ] and the also cursor comes Back when work is done and popup was added. All right and in right time. But the cursor disappears in that time instead of showing the busy cursor.
Can anybody help me???

I see there are problems with reading the code, try again:
click on a item (own component, extended Canvas, buttonMode = true)
call function by MouseListener
function {
    this.cursorManager.setBusyCursor();
    this.callLater(doPopUpWork);
callLater function
doPopUpWork {
    // DO WORK AND ADD POPUP
    this.cursoManager.removeBusyCursor();

The problem about MouseListener,MouseMotionListener

When I compile my program I face a problem with the compiled informatioin:
XYZApp.java:137: DisplayPanel should be declared abstract; it does not define mouseDragged(java.awt.event.MouseEvent) in DisplayPanel
class DisplayPanel extends JPanel implements MouseListener,MouseMotionListener
And the DisplayPanel class is below:
class DisplayPanel extends JPanel implements MouseListener,MouseMotionListener
DisplayPanel()
     {}//constructor
//Add or remove the mouse response
     public void PanelremoveMouseListener()
          removeMouseListener(this);
     public void PanelremoveMouseMotionListener()
          removeMouseMotionListener(this);
     public void PaneladdMouseListener()
          addMouseListener(this);
     public void PaneladdMouseMotionListener()
          addMouseMotionListener(this);
     public void MouseClicked(MouseEvent e)
          JOptionPane.showMessageDialog(this,"能响应鼠标");
public void MousePressed(MouseEvent e)
public void MouseReleaseed(MouseEvent e)
public void MouseEntered(MouseEvent e)
public void MouseExited(MouseEvent e)
public void MouseDraggeded(MouseEvent e)
public void MouseMoved(MouseEvent e)
What is the problem?

When you post code, please use [code] and [/code] tags as described in Formatting Help on the message entry page. It makes it much easier to read and prevents accidental markup from array indices like [i].
Error messages are really cool; they'll generally do a real good job of telling you what's wrong. Learn to read them - it's essential you understand them if you want to improve as a programmer.

Performance problems with UI grid of rectangles

Am looking for some help on how to program a specific user interface (UI). I need to create a large matrix (n x m) of rectangles, and give the user the ability to click and drag the mouse over them to select them. When a user clicks/drags over a rectangle, it should repaint itself a different color and store the fact that it was selected. Since the matrix is rather large, I want to put it in a JScrollPane so that the user can scroll over the entire matrix.
So far I have come up with two ways to do this, and one of them was horrendously slow. (It is unusable.) I would like some advice on how to do this to get the best UI performance so that I have a really slick and fast UI. The two methods I have tried are:
1. Create a new class called MyRectangle that extends java.awt.Rectangle. This is a pretty simple class that just adds a couple of instance vars to keep track of if it has been selected or not, and what color it should paint itself and its border. Next, I create a class called MyJPanel that extends JPanel. MyJPanel contains an (n x m) array of MyRectangles and overloads the paintComponent() method to paint them all on the panel. MyJPanel also implements the mouseListener(s) so it can tell when someone has pressed/clicked/ or dragged over it. When it receives a MouseEvent, it finds the correct MyRectangle (by comparing the point returned on MyJPanel), sets that MyRectangle's instance vars appropriately, and then calls UpdateUI().
Here is the problem with this design. That array of MyRectangles looks at least like this:
MyRectangle myRectangleArray[][] = new MyRectangle[50][200];
So, in the paintComponent() method of the MyJPanel, it has to iterate through the 50 * 200 rectangles in order to know how to paint each one on the screen. Not to mention the fact that at each one it has to do a comparision to determine how to set Graphics2D.setPaint( Color.XX ); for that specific rectangle. As mentioned, I have implemented this and it is EXCRUTIATINGLY SLOW. So, I moved on to....
2. Create a new class called MyJButton that extends javax.swing.JButton. MyJButton contains instance vars to note if it is selected or not, what its background color should be. MyJButton also implements the mouseListener(s) and handles all the MouseEvents themselves. Now, instead of having MyJPanel overload paintComponent() and handle all that myself, I just have it contain an (n x m) array of MyJButtons and just add them to the panel using a GridLayout. The problem here is that the mouseDragged event doesn't work quite the way I'd like. In order to implement mouseDragged, I have to create an interface and have each MyJButton callback to its container MyJPanel to tell it when / where the dragging started and stopped so that MyJPanel can update all the other MyJButtons. However, the performance seems to be much better and the user can click all over without causing the screen to lock up doing repaints.
Ok, here's my question. DOES ANYONE HAVE A BETTER WAY OF DOING THIS???
What I want is to present the user with an (n x m) matrix of rectangles (inside a scrollable pane). This matrix will be LARGE, like at least 50 x 200 and would prefer to go up to 70 x 500 or more. The size of each rectangle will need to be definable as the number of columns gets larger, I will need to make the size of the individual rectangles smaller. The user should be able to click and drag over these rectangles, and the program should store which row / column was selected, and should then paint those selected rectangles on the screen in a different (configurable) color.
Can anyone offer any help?
Don Osburn
[email protected]
[email protected]

using JTable is worth looking into, I did a quick test for speed purposes and this looks good if you do decide to go with a custom solution. Mouse processing shouldn't be too hard (the code for converting from user space to model space is in the paint method), but I can't figure out how to intercept mouse events properly (think this is done in the UI delegate or smt)
asjfimport javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class MatrixComponent extends JComponent {
 int rows, columns;
 int swidth, sheight;
 Dimension mySize;
 boolean [][] isSelected;
 Font myFont;
 public MatrixComponent(int rows, int columns, int w, int h) {
 this.rows = rows;
 this.columns = columns;
 this.swidth = w;
 this.sheight = h;
 this.mySize = new Dimension(columns*swidth,rows*sheight);
 this.isSelected = new boolean [columns][rows];
 this.myFont = new Font("Monotype",Font.PLAIN,8);
 public void paintComponent(Graphics g) {
 Rectangle clip = g.getClipBounds();
 int sx = clip.x/swidth;
 int ex = Math.min(1 + sx + clip.width/swidth, columns);
 int sy = clip.y/sheight;
 int ey = Math.min(1 + sy + clip.height/sheight, rows);
 g.setFont(myFont);
 for(int x=sx; x<ex; x++)
 for(int y=sy; y<ey; y++) {
 g.setColor(new Color(x*255/columns, y*255/rows, 100));
 g.drawRect(x*swidth,y*sheight,(swidth-1),(sheight-1));
 g.drawString(""+(x+y*columns),swidth/2+x*swidth,sheight/2+y*sheight);
 public Dimension getPreferredSize() {return mySize;}
 public Dimension getMaximumSize() {return mySize;}
 public Dimension getMinimumSize() {return mySize;}
 public static void main(String [] arg) throws Exception {
 JFrame frame = new JFrame("MatrixComponent");
 frame.getContentPane().add(new JScrollPane(new MatrixComponent(1000,1000,50,50)));
 frame.pack();
 frame.show();
}

Problem with viewing 2 albums with the same name in Cover flow

Hi if I have 2 albums with the same name ("The Best of" for example) but of 2 different artists there's a big problem with all idevices like iPhone...
So when I go in iPod app and I want to watch all albums in cover flow when I choose one of these 2 albums I'll find all the songs of both albums merged...

The MouseListener you use would have to know about both JPanels and both their repaint-methods when mouseClicked-method is called.
Something like this:
public class Repainter extends MouseAdapter {
private JPanel panel1;
private JPanel panel2;
public Repainter( JPanel panel1, JPanel panel2 ) {
this.panel1 = panel1;
this.panel2 = panel2;
public void mouseClicked( MouseEvent me ) {
panel1.repaint();
panel2.repaint();
Tell me if I misunderstood the question or if you have any further qestions.
/ Jeremia.

Problems with Overlay Layout - can anyone spot something wrong/missing?

Hi folks, I'm developing a tool that allows you to draw rectangles around objects on an image. The rectangles are then saved, and you can move between images. For some reason, though my rectangles are not drawing on the panel. I am using the Overlay Layout. Can anyone spot what I'm doing wrong? (The TopPanel canvas appears to be there, as it's taking input from the mouse - the problem is simply that the red rectangles are not drawing on the panel). Please help!!
So you know, there is a JFrame in another class which adds an instance of the ObjectMarker panel to it. It also provides buttons for using the next and previous Image methods.
Any other general advice is appreciated too.
* Object_Marker.java
* Created on 07 April 2008, 15:38
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import javax.imageio.ImageIO;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.OverlayLayout;
import javax.swing.event.MouseInputAdapter;
* @author Eric
public class ObjectMarker extends javax.swing.JPanel {
 private static final long serialVersionUID = 6574271353772129556L;
 File directory;
 String directory_path;
 Font big = new Font("SansSerif", Font.BOLD, 18);
 List<File> file_list = Collections.synchronizedList(new LinkedList<File>());
 String[] filetypes = { "jpeg", "jpg", "gif", "bmp", "tif", "tiff", "png" };
 // This Hashmap contains List of Rectangles, allowing me to link images to collections of rectangles through the value 'index'.
 public static HashMap<Integer, List<Rectangle>> collection = new HashMap<Integer, List<Rectangle>>();
 BufferedImage currentImage;
 Thread thread;
 Integer index = 0;
 OverlayLayout overlay;
 private TopPanel top;
 private JPanel pictureFrame;
 String newline = System.getProperty("line.separator");
 * Creates new form Object_Marker
 * @throws IOException
 public ObjectMarker(File directory) {
 System.out.println("Got in...");
 this.directory = directory;
 File[] temp = directory.listFiles();
 directory_path = directory.getPath();
 // Add all the image files in the directory to the linked list for easy
 // iteration.
 for (File file : temp) {
 if (isImage(file)) {
 file_list.add(file);
 initComponents();
 try {
 currentImage = ImageIO.read(file_list.get(index));
 } catch (IOException e) {
 System.out.println("There was a problem loading the image.");
 // 55 pixels offsets the height of the JMenuBar and the title bar
 // which are included in the size of the JFrame.
 this.setSize(currentImage.getWidth(), currentImage.getHeight() + 55);
 public String getImageList() {
 // Allows me to build the string gradually.
 StringBuffer list = new StringBuffer();
 list.append("Image files found in directory: \n\n");
 for (int i = 0; i < file_list.size(); i++) {
 list.append((((File) file_list.get(i))).getName() + "\n");
 return list.toString();
 private void initComponents() {
 top = new TopPanel();
 pictureFrame = new javax.swing.JPanel();
 OverlayLayout ol = new OverlayLayout(this);
 this.setLayout(ol);
 this.add(top);
 this.add(pictureFrame);
 * private void initComponents() {
 * javax.swing.GroupLayout pictureFrameLayout = new
 * javax.swing.GroupLayout(pictureFrame);
 * pictureFrame.setLayout(pictureFrameLayout);
 * pictureFrameLayout.setHorizontalGroup(
 * pictureFrameLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
 * .addGap(0, 497, Short.MAX_VALUE) ); pictureFrameLayout.setVerticalGroup(
 * pictureFrameLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
 * .addGap(0, 394, Short.MAX_VALUE) );
 * javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
 * this.setLayout(layout); layout.setHorizontalGroup(
 * layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
 * .addComponent(pictureFrame, javax.swing.GroupLayout.DEFAULT_SIZE,
 * javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) );
 * layout.setVerticalGroup(
 * layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
 * .addComponent(pictureFrame, javax.swing.GroupLayout.DEFAULT_SIZE,
 * javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) ); }
 * This function returns the extension of a given file, for example "jpg" or
 * "gif"
 * @param f
 * The file to examine
 * @return String containing extension
 public static String getExtension(File f) {
 String ext = null;
 String s = f.getName();
 int i = s.lastIndexOf('.');
 if (i > 0 && i < s.length() - 1) {
 ext = s.substring(i + 1).toLowerCase();
 } else {
 ext = "";
 return ext;
 public String getDetails() {
 saveRectangles();
 StringBuffer sb = new StringBuffer();
 for (int i = 0; i < file_list.size(); i++) {
 try{
 int count = collection.get(i).size();
 if (count > 0) {
 sb.append(file_list.get(i).getPath() + " "); // Add the
 // filename of
 // the file
 sb.append(count + " "); // Add the number of rectangles
 for (int j = 0; j < collection.get(i).size(); j++) {
 Rectangle current = collection.get(i).get(j);
 String coordinates = (int) current.getMinX() + " "
 + (int) current.getMinY() + " ";
 String size = ((int) current.getMaxX() - (int) current
 .getMinX())
 + " "
 + ((int) current.getMaxY() - (int) current
 .getMinY()) + " ";
 String result = coordinates + size;
 sb.append(result);
 sb.append(newline);
 } catch (NullPointerException e){
 // Do nothing. "int count = collection.get(i).size();"
 // will try to over count.
 return sb.toString();
 private boolean isImage(File f) {
 List<String> list = Arrays.asList(filetypes);
 String extension = getExtension(f);
 if (list.contains(extension)) {
 return true;
 return false;
 /** Draw the image on the panel. * */
 public void paint(Graphics g) {
 if (currentImage == null) {
 g.drawString("No image to display!", 300, 240);
 } else {
 // Draw the image
 g.drawImage(currentImage, 0, 0, this);
 // Write the index
 g.setFont(big);
 g.drawString(index + 1 + "/" + file_list.size(), 10, 25);
 public void nextImage() throws IOException {
 if (index < file_list.size() - 1) {
 printOutContents();
 System.out.println("Index: " + index);
 saveRectangles();
 index++;
 currentImage = ImageIO.read(file_list.get(index));
 this
 .setSize(currentImage.getWidth(),
 currentImage.getHeight() + 55);
 top.setSize(this.getSize());
 top.rectangle_list.clear();
 if (collection.size() > index) {
 loadRectangles();
 repaint();
 private void saveRectangles() {
 // If the current image's rectangles have not been changed, don't do
 // anything.
 if (collection.containsKey(index)) {
 System.out.println("Removing Index: " + index);
 collection.remove(index);
 collection.put(index, top.getRectangleList());
 System.out.println("We just saved " + collection.get(index).size()
 + " rectangles");
 System.out.println("They were saved in HashMap Location " + index);
 System.out.println("Proof: ");
 List<Rectangle> temp = collection.get(index);
 for (int i = 0; i < temp.size(); i++) {
 System.out.println("Rectangle " + (i + 1) + ": " + temp.get(i));
 // If the rectangle list has changed, set the list the current index
 // as the new list.
 private void loadRectangles() {
 System.out.println("We just loaded index " + index
 + " into temporary memory.");
 System.out.println("Proof: ");
 List<Rectangle> temp = collection.get(index);
 top.rectangle_list = collection.get(index);
 for (int i = 0; i < temp.size(); i++) {
 System.out.println("Rectangle " + (i + 1) + ": " + temp.get(i));
 private void printOutContents() {
 System.out.println();
 System.out.println("Contents printout...");
 for (int i = 0; i < collection.size(); i++) {
 for (Rectangle r : collection.get(i)) {
 System.out.println("In collection index: " + i + " Rectangle "
 + r.toString());
 System.out.println();
 public void previousImage() throws IOException {
 if (index >= 1) {
 printOutContents();
 System.out.println("Index: " + index);
 saveRectangles();
 index--;
 currentImage = ImageIO.read(file_list.get(index));
 this
 .setSize(currentImage.getWidth(),
 currentImage.getHeight() + 55);
 top.setSize(this.getSize());
 top.rectangle_list.clear();
 if (index >= 0) {
 loadRectangles();
 repaint();
 public void removeLastRectangle() {
 // This method removes the most recent rectangle added.
 try {
 int length = collection.get(index).size();
 collection.get(index).remove(length - 1);
 } catch (NullPointerException e) {
 try {
 top.rectangle_list.remove(top.rectangle_list.size() - 1);
 } catch (IndexOutOfBoundsException ioobe) {
 JOptionPane.showMessageDialog(this, "Cannot undo any more!");
* Class developed from SSCCE found on Java forum:
* http://forum.java.sun.com/thread.jspa?threadID=647074&messageID=3817479
* @author 74philip
class TopPanel extends JPanel {
 List<Rectangle> rectangle_list;
 private static final long serialVersionUID = 6208367976334130998L;
 Point loc;
 int width, height, arcRadius;
 Rectangle temp; // for mouse ops in TopRanger
 public TopPanel() {
 setOpaque(false);
 rectangle_list = Collections
 .synchronizedList(new LinkedList<Rectangle>());
 TopRanger ranger = new TopRanger(this);
 addMouseListener(ranger);
 addMouseMotionListener(ranger);
 public List<Rectangle> getRectangleList() {
 List<Rectangle> temporary = Collections
 .synchronizedList(new LinkedList<Rectangle>());
 temporary.addAll(rectangle_list);
 return temporary;
 protected void paintComponent(Graphics g) {
 super.paintComponent(g);
 Graphics2D g2 = (Graphics2D) g;
 g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
 RenderingHints.VALUE_ANTIALIAS_ON);
 g2.setPaint(Color.red);
 // Draw all the rectangles in the rectangle list.
 for (int i = 0; i < rectangle_list.size(); i++) {
 g2.drawRect(rectangle_list.get(i).x, rectangle_list.get(i).y,
 rectangle_list.get(i).width, rectangle_list.get(i).height);
 if (temp != null) {
 g2.draw(temp);
 public void loadRectangleList(List<Rectangle> list) {
 rectangle_list.addAll(list);
 public void addRectangle(Rectangle r) {
 rectangle_list.add(r);
class TopRanger extends MouseInputAdapter {
 TopPanel top;
 Point offset;
 boolean dragging;
 public TopRanger(TopPanel top) {
 this.top = top;
 dragging = false;
 public void mousePressed(MouseEvent e) {
 Point p = e.getPoint();
 top.temp = new Rectangle(p, new Dimension(0, 0));
 offset = new Point();
 dragging = true;
 top.repaint();
 public void mouseReleased(MouseEvent e) {
 dragging = false;
 // update top.r
 System.out.println(top.getRectangleList().size() + ": Object added: "
 + top.temp.toString());
 top.addRectangle(top.temp);
 top.repaint();
 public void mouseDragged(MouseEvent e) {
 if (dragging) {
 top.temp.setBounds(top.temp.x, top.temp.y, e.getX() - top.temp.x, e
 .getY()
 - top.temp.y);
 top.repaint();
}Regards,
Eric

Alright so I fixed it! I created a new class called BottomPanel extends JPanel, which I then gave the responsibility of drawing the image. I gave it an update method which took the details of the currentImage and displayed it on the screen.
If anybody's interested I also discovered/solved a problem with my mouseListener - I couldn't drag backwards. I fixed this by adding tests looking for negative widths and heights. I compensated accordingly by reseting the rectangle origin to e.getX(), e.getY() and by setting the to original_origin.x - e.getX() and original_origin.y - e.getY().
No problem!

Problem with an array

i have problem with my program i implement saveing method
but when i open file( game.txt) it does not update my board it return same postion every time i same game
chess class Jframe(Jfilechooser)(call an board array)---->
Gui Japplet class( call and board array------------>
Board(class Jpanel have board array)
it does not update borad array
it just call it once in start and return the same value every time
classChess(){
ChessPlayer java = new ChessPlayer();
public void saveData()
 File file = null;
 JFileChooser fc = new JFileChooser();
 fc.setCurrentDirectory(new File("."));
 fc.setDialogTitle("Save Text As...");
 int returnVal = fc.showSaveDialog(this);
 if (returnVal == JFileChooser.APPROVE_OPTION)
 { file = fc.getSelectedFile();
 try
 { PrintWriter out =
 new PrintWriter(
 new BufferedWriter(
 new FileWriter(file)));
 //while for all the moves in the array>
for (int i=0;i<120;i++)
 out.println( java.saveDAta(i));
 out.println("\n");
 out.close();
 catch (IOException e) {
 // Some error has occured while trying to read the file.
 // Show an error message.
 JOptionPane.showMessageDialog(this,
 "Sorry, some error occurred:\n" + e.getMessage());}
public static void main(String[] args) {
JPopupMenu.setDefaultLightWeightPopupEnabled(false);
 JFrame frame = new ChessMan();
 Container content = frame.getContentPane();
 ChessMan f = new ChessMan();
 //japplet
 ChessPlayer javaAppletication = new ChessPlayer();
 javaAppletication.init();
 javaAppletication.start();
 }Gui
[Gui]
class Gui{
int [] board = new int [120];
 int [] boardcolor = new int [120];
Board check = new Board(this,false);
{public void init()
 { // Create new Border
 contentPane = getContentPane();
 bboard = new Board(this,false);
public String saveDAta(int i)
String l=check. save(i);
return (l);
and finally board Jpanel
class Board extends JPanel
{public Board (JApplet useapplet,boolean bool) {
 setup();
{ public String save(int i)
 { String l;
 if (color==1)
 {System.out.println("notpossible");}
 l = board[i]+"$"+boardColor;
return l;
thanks guys

My Jframe
public class ChessMan extends JFrame implements ActionListener, WindowListener {
JMenuItem saveItem, loadItem, copyItem, pasteItem;
JMenu fileMenu, editMenu;
JMenuBar bar;
ChessPlayer java = new ChessPlayer();
public ChessMan() { setTitle("CHESS PLAYER GAME" );
setSize(200,300);
System.out.println("\n"); }
addWindowListener(new java.awt.event.WindowAdapter()
 { public void windowClosing(java.awt.event.WindowEvent e)
 { System.exit(0); } });
JMenu fileMenu = new JMenu("File");
saveItem = new JMenuItem("Save");
saveItem.setActionCommand("save");
saveItem.setAccelerator( KeyStroke.getKeyStroke("ctrl S"));
saveItem.addActionListener(this);
fileMenu.add(saveItem);
loadItem = new JMenuItem("Load");
loadItem.setActionCommand("load");
loadItem.setAccelerator( KeyStroke.getKeyStroke("ctrl L"));
loadItem.addActionListener(this);
fileMenu.add(loadItem);
JMenu editMenu = new JMenu("About");
copyItem = new JMenuItem("Help");
copyItem.setActionCommand("Help");
copyItem.setAccelerator( KeyStroke.getKeyStroke("ctrl H"));
copyItem.addActionListener(this);
editMenu.add(copyItem);
pasteItem = new JMenuItem("Exit");
pasteItem.setActionCommand("Exit");
pasteItem.setAccelerator( KeyStroke.getKeyStroke("ctrl E"));
pasteItem.addActionListener(this);
editMenu.add(pasteItem);
JMenuBar bar = new JMenuBar();
bar.add(fileMenu);
bar.add(editMenu);
setJMenuBar(bar);
setVisible(true);
setLocation(0,0);
public void actionPerformed(ActionEvent e) {
JMenuItem item = (JMenuItem)e.getSource();
String ac = item.getActionCommand();
System.out.println("ac = "+ ac);
// you can use action commands to track menu item events
if(ac.equals("save"))
 {System.out.println("ac.equals(\"save\") = "+ ac.equals("save"));
 saveData();}
if(ac.equals("load"))
{System.out.println("ac.equals(\"load\") = "+ ac.equals("load"));
 loadingData();}
 if(ac.equals("Help"))
{System.out.println("ac.equals(\"load\") = "+ ac.equals("Help"));
if(ac.equals("Exit"))
{System.out.println("ac.equals(\"load\") = "+ ac.equals("Exit"));
 Exit();}
// the event origin
if(item == saveItem)
 System.out.println("item = "+ item.toString().substring
 (item.toString().indexOf("text=") + 5, item.toString().lastIndexOf("]")));
if(item == loadItem)
 System.out.println("item = "+ item);
// System.out.print( java.saveDAta());
public void saveData()
 File file = null;
 JFileChooser fc = new JFileChooser();
 fc.setCurrentDirectory(new File("."));
 fc.setDialogTitle("Save Text As...");
 int returnVal = fc.showSaveDialog(this);
 if (returnVal == JFileChooser.APPROVE_OPTION)
 { file = fc.getSelectedFile();
 try
 { PrintWriter out =
 new PrintWriter(
 new BufferedWriter(
 new FileWriter(file)));
 //while for all the moves in the array>
for (int i=0;i<120;i++)
 out.println( java.saveDAta(i));
 out.println("\n");
 out.close();
 catch (IOException e) {
 // Some error has occured while trying to read the file.
 // Show an error message.
 JOptionPane.showMessageDialog(this,
 "Sorry, some error occurred:\n" + e.getMessage());}
 public void loadingData()
 File loadfile = null;
 JFileChooser fc = new JFileChooser();
 fc.setDialogTitle("OpenFile...");
 fc.setCurrentDirectory(new File("."));
 int returnVal = fc.showOpenDialog(this);
 if (returnVal == JFileChooser.APPROVE_OPTION)
 { loadfile = fc.getSelectedFile();
 try
 { PrintWriter out =
 new PrintWriter(
 new BufferedWriter(
 new FileWriter(loadfile)));
 //while for all the moves in the array>
 out.println("��");
 out.println("\n");
 out.close();
 catch (IOException e) {
 // Some error has occured while trying to read the file.
 // Show an error message.
 JOptionPane.showMessageDialog(this,
 "Sorry, some error occurred:\n" + e.getMessage());}
public void Exit()
System.exit(0);
public static void main(String[] args) {
JPopupMenu.setDefaultLightWeightPopupEnabled(false);
 JFrame frame = new ChessMan();
 Container content = frame.getContentPane();
 ChessMan f = new ChessMan();
 f.setLocation(300,300);
 f.show();
 ImageIcon customImageIcon = new ImageIcon("ac516.gif");
 Image customImage = customImageIcon.getImage();
 frame.setIconImage(customImage);
 //japplet
 ChessPlayer javaAppletication = new ChessPlayer();
 // i could not put my constructor here <Static>
javaAppletication.init();
javaAppletication.start();
// for(int i=0; i < .length(); i++)
content.add(javaAppletication, BorderLayout.CENTER);
 frame.getContentPane();
javaAppletication.setBackground (Color.black);
 frame.setVisible(true);
frame.show();
frame.pack(); // invokes getPreferredSize()
// invokes paint();
public void windowOpened(WindowEvent e) {
fileMenu.doClick();
public void windowClosing(WindowEvent e) {}
public void windowClosed(WindowEvent e) {}
public void windowIconified(WindowEvent e) {}
public void windowDeiconified(WindowEvent e) {}
public void windowActivated(WindowEvent e) {}
public void windowDeactivated(WindowEvent e) {}
My Japplet Class
class ChessPlayer extends JApplet
 implements ActionListener,MouseListener
int c;
 //Reference for new Board
 Board bboard;
 //Reference for Button
 JButton newgame,undo,onePlayer,TwoPlayer,NormalPieceSet,
 FuunyPieceSet,startButton,stopButton;
 //Reference for Label
 JLabel message;
 //Reference for new Panel
 JPanel buttonpanel2,buttonpanel,messagepanel,buttonpane;
 //Initilize the Applet
 DemoAnimation Demo;
 Container contentPane;
 Board check = new Board(this,false);
 int [] board = new int [120];
 int [] boardcolor = new int [120];
 public void init()
 // Create new Border
 contentPane = getContentPane();
 check = new Board(this,false);
 bboard = new Board(this,false);
 bboard.setPreferredSize(new Dimension(500,400));
 bboard.setBorder(BorderFactory.createLineBorder( Color.red ) );
 contentPane.add(bboard);
 final ImageIcon image = new ImageIcon("ac516.gif");
 bboard.addMouseListener(this);
 bboard.setBackground (Color.black);
 BorderLayout text=new BorderLayout();
 Demo = new DemoAnimation( this );
 Demo.setPreferredSize(new Dimension(160, 500));
 contentPane.add(Demo);
 // Set Background Black
 contentPane.setBackground (Color.black);
 contentPane.setLayout (new BorderLayout (50,50));
 // set new Font "TimesRoman"
 Font Text= new Font("TimesRoman", Font.BOLD,15);
 //panel to keep buttons together
 buttonpanel=new JPanel();
 buttonpanel.setLayout(new GridLayout(1,2,6,0));
 buttonpanel.add(newgame=new JButton("new game",image));
 newgame.addActionListener(this);
 buttonpanel.add(undo=new JButton("undo"));
 undo.addActionListener(this);
 // Create new Choice Panel
 buttonpanel2 = new JPanel();
 buttonpanel2.setLayout(new GridLayout(6,1,0,10));
 buttonpanel2.add(onePlayer=new JButton("Change Colour"));
 onePlayer.addActionListener(this);
 buttonpanel2.add(TwoPlayer=new JButton("Statistic"));
 TwoPlayer.addActionListener(this);
 buttonpanel2.add(NormalPieceSet=new JButton("Quit"));
 NormalPieceSet.addActionListener(this);
 buttonpanel2.add(FuunyPieceSet=new JButton("Change Piece"));
 FuunyPieceSet.addActionListener(this);
 buttonpanel2.add(startButton = new JButton("Start Animation"));
 startButton.addActionListener(this);
 buttonpanel2.add(stopButton = new JButton("Stop Animation"));
 stopButton.addActionListener(this);
 contentPane.add(BorderLayout.WEST, demopanel);
// Set Font For Text Message
 setFont(Text);
 messagepanel=new JPanel();
 messagepanel.setBorder(BorderFactory.createLineBorder( Color.red ) );
 messagepanel.setBackground(Color.black);
// essagepanel.setLayout(new GridLayout(1,1));
 // Create new Label
 messagepanel.add(message = new JLabel());
 setMessage("Welcome");
 // Postion panels in Layout
 contentPane.add("North",buttonpanel);
 contentPane.add("East",buttonpanel2);
 contentPane.add ("South",messagepanel);
 contentPane.add ("Center",bboard);
 contentPane.add("West",Demo);
public void mouseReleased(java.awt.event.MouseEvent e)
{ statuseChange();}
public void mouseClicked(java.awt.event.MouseEvent e)
public void mouseEntered(java.awt.event.MouseEvent e) {
public void mouseExited(java.awt.event.MouseEvent e) {
public void mouseMoved(java.awt.event.MouseEvent e) {
statuseChange();
public void mousePressed(java.awt.event.MouseEvent e)
{statuseChange();
public void actionPerformed(ActionEvent e)
 Object source=e.getSource();
 if (source == newgame)
 { bboard.newgame();
 yellow();
 setMessage("try again");
 pause(100);
 c=add(c);
 else if (source==undo)
 yellow();
 bboard.undo();
 setMessage("Undo");
 else if (source== TwoPlayer )
 //bboard.setup();
 yellow();
 setMessage("Starting new Game");
 setMessage("Change Color");
 else if(source == FuunyPieceSet)
 {yellow();
 setMessage("game played::" +c);
 bboard.PieceChange();
 else if(source == NormalPieceSet)
 {yellow();
 setMessage("GOODBYE");
 destroy();
 else if(source == startButton)
 {yellow();
 setMessage("Start Animation");
 Demo.start();
 else if(source == stopButton)
 {yellow();
 setMessage("Stop Animation");
 Demo.stop();
 else if(source == onePlayer)
 {setMessage("");
 bboard.changePiece();
 setMessage("Change Color");
 public void statuseChange()
 switch (bboard.gameStatus())
 case 1:
 red();
 setMessage("White won");
 break;
case 2:
 red();
 setMessage("Black won");
 break;
case 3:
 red();
 setMessage("DRAW");
 Demo.changeAnimation(2);
 break;
case 4:
 white();
 setMessage("White Turn");
 Demo.changeAnimation(1);
 break;
case 5:
 green();
 setMessage("Black turn");
 Demo.changeAnimation(3);
 break;
case 6:
 red();
 setMessage(" Check");
 Demo.changeAnimation(4);
 break;
case 7:
 red();
 setMessage("Check");
 Demo.changeAnimation(4);
 break;
case 8:
 yellow();
 setMessage("I Hope you enjoyed it");
public String saveDAta(int i)
String l=check.save(i);
return (l);
public void LoadData(String load)
public void setMessage(String s)
 /*The string s will be shown to the user.*/
 Font Text= new Font("Courier", Font.BOLD,30);
 message.setText(s);
 message.setFont(Text);
 public void white()
 { message.setForeground(Color.white);}
 public void green()
 message.setForeground(Color.green);
 public void red()
 message.setForeground(Color.red);
 public void yellow()
 message.setForeground(Color.yellow);
 // pause method
 void pause(int time)
try {Thread.sleep(time);
} catch (InterruptedException e)
 // Create new inset Object
 public Insets getInsets()
 return new Insets(50,220,150,200);
public void destroy()
contentPane.remove(buttonpanel2);
contentPane.remove(buttonpanel);
contentPane.remove(bboard);
contentPane.repaint();
Demo.start();
public int add(int x)
 { int b=x+1;
 return b;
}tanx man i dont the other two because they are to long
my is when i open jframe
i think Japplet and Jframe can not commuinicate to each other

Problem with java.awt.MouseInfo or java.awt.event.*;

I have a problem with the MouseInfo class. I think.. because in my mousePressed(MouseEvent event) method, I have this:
     public void mousePressed(MouseEvent event) {
          pInfo = mInfo.getPointerInfo();
          point = pInfo.getLocation();
          pointX = point.getX();
          pointY = point.getY();
          System.out.println("pointer is at: (" + (int)pointX + ", " + (int)pointY + ")");
     }I think you all could figure out what this does. I declared the variables at the top and I implemented MouseListener... when I click it doesnt tell me the X and Y coords.
Alright, thanks. Any help appreciated.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class MouseExample extends MouseAdapter implements Runnable {
    @Override
    public void mousePressed(MouseEvent event) {
        int x = event.getX();
        int y = event.getY();
        System.out.println("x=" + x + ", y=" + y);
    @Override
    public void run() {
        JLabel label = new JLabel("Click anywhere", SwingConstants.CENTER);
        label.setPreferredSize(new Dimension(300, 200));
        label.addMouseListener(this);
        JFrame f = new JFrame();
        f.getContentPane().add(label);
        f.pack();
        f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    public static void main(String[] args) {
        EventQueue.invokeLater(new MouseExample());
}

A problem with threads

I am trying to implement some kind of a server listening for requests. The listener part of the app, is a daemon thread that listens for connections and instantiates a handling daemon thread once it gets some. However, my problem is that i must be able to kill the listening thread at the user's will (say via a sto button). I have done this via the Sun's proposed way, by testing a boolean flag in the loop, which is set to false when i wish to kill the thread. The problem with this thing is the following...
Once the thread starts excecuting, it will test the flag, find it true and enter the loop. At some point it will LOCK on the server socket waiting for connection. Unless some client actually connects, it will keep on listening indefinatelly whithought ever bothering to check for the flag again (no matter how many times you set the damn thing to false).
My question is this: Is there any real, non-theoretical, applied way to stop thread in java safely?
Thank you in advance,
Lefty

This was one solution from the socket programming forum, have you tried this??
public Thread MyThread extends Thread{
     boolean active = true;
     public void run(){
          ss.setSoTimeout(90);
          while (active){
               try{
                    serverSocket = ss.accept();
               catch (SocketTimeoutException ste){
               // do nothing
     // interrupt thread
     public void deactivate(){
          active = false;
          // you gotta sleep for a time longer than the
          // accept() timeout to make sure that timeout is finished.
          try{
               sleep(91);
          }catch (InterruptedException ie){
          interrupt();
}

Problem with Threads and a static variable

I have a problem with the code below. I am yet to make sure that I understand the problem. Correct me if I am wrong please.
Code functionality:
A timer calls SetState every second. It sets the state and sets boolean variable "changed" to true. Then notifies a main process thread to check if the state changed to send a message.
The problem as far I understand is:
Assume the timer Thread calls SetState twice before the main process Thread runs. As a result, "changed" is set to true twice. However, since the main process is blocked twice during the two calls to SetState, when it runs it would have the two SetState timer threads blocked on its synchronized body. It will pass the first one, send the message and set "changed" to false since it was true. Now, it will pass the second thread, but here is the problem, "changed" is already set to false. As a result, it won't send the message even though it is supposed to.
Would you please let me know if my understanding is correct? If so, what would you propose to resolve the problem? Should I call wait some other or should I notify in a different way?
Thanks,
B.D.
Code:
private static volatile boolean bChanged = false;
private static Thread objMainProcess;
   protected static void Init(){
        objMainProcess = new Thread() {
            public void run() {
                while( objMainProcess == Thread.currentThread() ) {
                   GetState();
        objMainProcess.setDaemon( true );
        objMainProcess.start();
    public static void initStatusTimer(){
        if(objTimer == null)
             objTimer = new javax.swing.Timer( 1000, new java.awt.event.ActionListener(){
                public void actionPerformed( java.awt.event.ActionEvent evt){
                          SetState();
    private static void SetState(){
        if( objMainProcess == null ) return;
        synchronized( objMainProcess ) {
            bChanged = true;
            try{
                objMainProcess.notify();
            }catch( IllegalMonitorStateException e ) {}
    private static boolean GetState() {
        if( objMainProcess == null ) return false;
        synchronized( objMainProcess ) {
            if( bChanged) {
                SendMessage();
                bChanged = false;
                return true;
            try {
                objMainProcess.wait();
            }catch( InterruptedException e ) {}
            return false;
    }

Thanks DrClap for your reply. Everything you said is right. It is not easy to make them alternate since SetState() could be called from different places where the state could be anything else but a status message. Like a GREETING message for example. It is a handshaking message but not a status message.
Again as you said, There is a reason I can't call sendMessage() inside setState().
The only way I was able to do it is by having a counter of the number of notifies that have been called. Every time notify() is called a counter is incremented. Now instead of just checking if "changed" flag is true, I also check if notify counter is greater than zero. If both true, I send the message. If "changed" flag is false, I check again if the notify counter is greater than zero, I send the message. This way it works, but it is kind of a patch than a good design fix. I am yet to find a good solution.
Thanks,
B.D.

Problem with threads running javaw

Hi,
Having a problem with multi thread programming using client server sockets. The program works find when starting the the application in a console using java muti.java , but when using javaw multi.java the program doesnt die and have to kill it in the task manager. The program doesnt display any of my gui error messages either when the server disconnect the client. all works find in a console. any advice on this as I havent been able to understand why this is happening? any comment would be appreciated.
troy.

troy,
Try and post a minimum code sample of your app which
does not work.
When using javaw, make sure you redirect the standard
error and standard output streams to file.
Graeme.Hi Graeme,
I dont understand what you mean by redirection to file? some of my code below.
The code works fine under a console, code is supposed to exit when the client (the other server )disconnects. the problem is that but the clientworker side of the code still works. which under console it doesnt.
public class Server{
ServerSocket aServerSocket;
Socket dianosticsSocket;
Socket nPortExpress;
ClientListener aClientListener;
LinkedList queue = new LinkedList();
int port = 0;
int clientPort = 0;
String clientName = null;
boolean serverAlive = true;
* Server constructor generates a server
* Socket and then starts a client threads.
* @param aPort      socket port of local machine.
public Server(int aPort, String aClientName, int aClientPort){
port = aPort;
clientName = aClientName;
clientPort = aClientPort;
try{
// create a new thread
aServerSocket = new ServerSocket(port) ;
// connect to the nPortExpress
aClientListener = new ClientListener(InetAddress.getByName(clientName), clientPort, queue,this);
// aClientListener.setDaemon(true);
aClientListener.start();
// start a dianostic port
DiagnosticsServer aDiagnosticsServer = new DiagnosticsServer(port,queue,aClientListener);
// System.out.println("Server is running on port " + port + "...");
// System.out.println("Connect to nPort");
catch(Exception e)
// System.out.println("ERROR: Server port " + port + " not available");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Server port " + port + " not available", JOptionPane.ERROR_MESSAGE);
serverAlive = false;
System.exit(1);
while(serverAlive&&aClientListener.hostSocket.isConnected()){
try{
// connect the client
Socket aClient = aServerSocket.accept();
//System.out.println("open client connection");
//System.out.println("client local: "+ aClient.getLocalAddress().toString());
// System.out.println("client localport: "+ aClient.getLocalPort());
// System.out.println("client : "+ aClient.getInetAddress().toString());
// System.out.println("client port: "+ aClient.getLocalPort());
// make a new client thread
ClientWorker clientThread = new ClientWorker(aClient, queue, aClientListener, false);
// start thread
clientThread.start();
catch(Exception e)
//System.out.println("ERROR: Client connection failure");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Client connection failure", JOptionPane.ERROR_MESSAGE);
}// end while
} // end constructor Server
void serverExit(){
     JOptionPane.showMessageDialog(null, "Server ","ERROR: nPort Failure", JOptionPane.ERROR_MESSAGE);
     System.exit(1);
}// end class Server
*** connect to another server
public class ClientListener extends Thread{
InetAddress hostName;
int hostPort;
Socket hostSocket;
BufferedReader in;
PrintWriter out;
boolean loggedIn;
LinkedList queue;      // reference to Server queue
Server serverRef; // reference to main server
* ClientListener connects to the host server.
* @param aHostName is the name of the host eg server name or IP address.
* @param aHostPort is a port number of the host.
* @param aLoginName is the users login name.
public ClientListener(InetAddress aHostName, int aHostPort,LinkedList aQueue,Server aServer)      // reference to Server queue)
hostName = aHostName;
hostPort = aHostPort;
queue = aQueue;
serverRef = aServer;
// connect to the server
try{
hostSocket = new Socket(hostName, hostPort);
catch(IOException e){
//System.out.println("ERROR: Connection Host Failed");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Connection to nPort Failed", JOptionPane.ERROR_MESSAGE);
System.exit(0);
} // end constructor ClientListener
** multi client connection server
ClientWorker(Socket aSocket,LinkedList aQueue, ClientListener aClientListener, boolean diagnostics){
queue = aQueue;
addToQueue(this);
client = aSocket;
clientRef = aClientListener;
aDiagnostic = diagnostics;
} // end constructor ClientWorker
* run method is the main loop of the server program
* in change of handle new client connection as well
* as handle all messages and errors.
public void run(){
boolean alive = true;
String aSubString = "";
in = null;
out = null;
loginName = "";
loggedIn = false;
while (alive && client.isConnected()&& clientRef.hostSocket.isConnected()){
try{
in = new BufferedReader(new InputStreamReader(client.getInputStream()));
out = new PrintWriter(new OutputStreamWriter(client.getOutputStream()));
if(aDiagnostic){
out.println("WELCOME to diagnostics");
broadCastDia("Connect : diagnostics "+client.getInetAddress().toString());
out.flush();
else {
out.println("WELCOME to Troy's Server");
broadCastDia("Connect : client "+client.getInetAddress().toString());
     out.flush();
String line;
while(((line = in.readLine())!= null)){
StringTokenizer aStringToken = new StringTokenizer(line, " ");
if(!aDiagnostic){
broadCastDia(line);
clientRef.sendMessage(line); // send mesage out to netExpress
out.println(line);
out.flush();
else{
if(line.equals("GETIPS"))
getIPs();
else{
clientRef.sendMessage(line); // send mesage out to netExpress
out.println(line);
out.flush();
} // end while
catch(Exception e){
// System.out.println("ERROR:Client Connection reset");
                         JOptionPane.showMessageDialog(null, (e.toString()),"ERROR:Client Connection reset", JOptionPane.ERROR_MESSAGE);
try{
if(aDiagnostic){
broadCastDia("Disconnect : diagnostics "+client.getInetAddress().toString());
out.flush();
else {
broadCastDia("Disconnect : client "+client.getInetAddress().toString());
     out.flush();
// close the buffers and connection;
in.close();
out.close();
client.close();
// System.out.println("out");
// remove from list
removeThreadQueue(this);
alive = false;
catch(Exception e){
// System.out.println("ERROR: Client Connection reset failure");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Client Connection reset failure", JOptionPane.ERROR_MESSAGE);
}// end while
} // end method run
* method run - Generates io stream for communicating with the server and
* starts the client gui. Run also parses the input commands from the server.
public void run(){
boolean alive = true;
try{
// begin to life the gui
// aGuiClient = new ClientGui(hostName.getHostName(), hostPort, loginName, this);
// aGuiClient.show();
in = new BufferedReader(new InputStreamReader(hostSocket.getInputStream()));
out = new PrintWriter(new OutputStreamWriter(hostSocket.getOutputStream()));
while (alive && hostSocket.isConnected()){
String line;
while(((line = in.readLine())!= null)){
System.out.println(line);
broadCast(line);
} // end while
} // end while
catch(Exception e){
//     System.out.println("ERRORa Connection to host reset");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Connection to nPort reset", JOptionPane.ERROR_MESSAGE);
try{
hostSocket.close();
     }catch(Exception a){
     JOptionPane.showMessageDialog(null, (a.toString()),"ERROR: Exception", JOptionPane.ERROR_MESSAGE);
alive = false;
System.exit(1);
} // end method run

Problem with threads and camera.

Hi everybody!
I've a problem with taking snapshot.
I would like to display a loading screen after it take snapshot ( sometimes i
have to wait few seconds after i took snapshot. Propably photo is being taken in time where i have to wait).
I was trying to use threads but i didn't succeed.
I made this code:
display.setCurrent(perform);
        new Thread(new Runnable(){
            public void run() {
                while((!performing.isShown()) && (backgroundCamera.isShown())){
                    Thread.yield();
                notifyAll();
        }).start();
        new Thread(new Runnable(){
            public void run() {
                try {
                    this.wait();
                } catch(Exception e) {
                    exceptionHandler(e);
                photo = camera.snapshot();
                display.setCurrent(displayPhoto);
        }).start();This code is sometimes showing performing screen but sometimes no.
I don't know why. In my opinion performing.isShown() method isn't working correctly.
Does anyone have some idea how to use threads here?

Hi,
I've finally managed to work this fine.
The code:
       Object o = new Object();
       display.setCurrent(perform);
        new Thread(new Runnable(){
            public void run() {
                while(!performing.isShown()){
                    Thread.yield();
               synchronized(o) {
                  o.notify();
        }).start();
        new Thread(new Runnable(){
            public void run() {
                try {
                    synchronized(o) {
                       o.wait(1);
                } catch(Exception e) {
                    exceptionHandler(e);
                photo = camera.snapshot();
                display.setCurrent(displayPhoto);
        }).start();

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