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Message:

mouseDragged

Posted by shim on October 31, 2001 at 2:50 AM

> Hi Jon
> I have developed an application ( same as you want client-server) in which you can draw a free hand picture on client and that picture will be drawn on server. There are four classes involed
> 1) ALine
> 2) DPanel
> 3) DClient
> 4) DServer
> I have attached all these four files in this posting. Copy them and put them in four files ALine.java, DPanel.java, DClient.java and DServer.java . Then compile these files. First run DServer class and then click on the button "Start Server". Then run DClient class and draw some free hand picture by just dragging your mouse and you can see these picure on server screen.
> The code is not optimized. It is only for demo purpose. If you need some improvement you can do it. You want to run the client and server on different machine then change SERVER and PORT variables in DPanel.java.
> If you need any help , let me know.
> Thanx
> Kishori

> ////////// Start of ALine.java
> import java.io.* ;

> public class ALine implements Serializable {
> private int x1 = 0 ;
> private int x2 = 0 ;
> private int y1 = 0 ;
> private int y2 = 0 ;
>
> public ALine ( ) {
> }
>
> public ALine ( int x1, int y1, int x2, int y2 ) {
> this.x1 = x1 ;
> this.y1 = y1 ;
> this.x2 = x2 ;
> this.y2 = y2 ;
> }
>
> public int getX1 ( ) {
> return x1 ;
> }
>
> public int getY1 ( ) {
> return y1 ;
> }

> public int getX2 ( ) {
> return x2 ;
> }

> public int getY2 ( ) {
> return y2 ;
> }
>
> }

> ////////////End of ALine.java

> ////////////Start of DPanel.java
> import java.io.* ;
> import java.net.* ;
> import java.awt.* ;
> import java.awt.event.* ;
> import javax.swing.* ;

>
> public class DPanel extends JPanel {
> private int x1 = 0 ;
> private int x2 = 0 ;
> private int y1 = 0 ;
> private int y2 = 0 ;
>
> public final static String SERVER = "127.0.0.1" ;
> public final static int PORT = 8888 ;
>
> // Socket to connect to server
> Socket connection = null ;
>
> ObjectOutputStream out = null ;
>
> // Flag to indicated that connection to server is ok
> boolean connected = false ;
>
> // Client or server panel
> private boolean client = true ;
>
>
> public DPanel ( boolean client ) {
> super ( ) ;
>
> this.client = client ;
>
> // For client add mouse motion listenr
> if ( client ) {
> addMouseMotionListener ( new MouseMotionAdapter ( ) {
> public void mouseMoved ( MouseEvent e ) {
> x1 = e.getX ( ) ;
> y1 = e.getY ( ) ;
> }
>
> public void mouseDragged ( MouseEvent e ) {
> x2 = e.getX ( ) ;
> y2 = e.getY ( ) ;
> repaint ( ) ;
> }
>
> }
> ) ;
>
> try {
> // Create the socket
> connection = new Socket ( SERVER, PORT ) ;
>
> // Get the output stream to send the data to server
> out = new ObjectOutputStream ( connection.getOutputStream ( ) ) ;
> connected = true ;
> }
> catch ( Exception e ) {
> System.out.println ( "Cound not establish connection with server\n" + e.getMessage ( ) ) ;
> }
> }
>
>
> }
>
> public void paint ( Graphics g ) {
> // If connected to server then send the line coordinates to server
> if ( connected && client ) {
> try {
> out.writeObject ( new ALine ( x1, y1, x2, y2 ) ) ;
> out.flush ( ) ;
> }
> catch ( Exception e ) {
> System.out.println ( "Could not wtire a line coordinates to server" + e.getMessage ( ) ) ;
> }
> }
>
> g.drawLine ( x1, y1, x2, y2 ) ;
> //Reset the starting point
> x1 = x2 ;
> y1 = y2 ;
> }
>
> public void setLine ( ALine line ) {
> this.x1 = line.getX1 ( ) ;
> this.y1 = line.getY1 ( ) ;
> this.x2 = line.getX2 ( ) ;
> this.y2 = line.getY2 ( ) ;
>
> if ( !client ) {
> System.out.println ( "Got a line (" + x1 + ", " + y1 + ", " + x2 + ", " + y2 + ")" ) ;
> }
> }
>
>
> public void setPoints ( int x1, int y1, int x2, int y2 ) {
> this.x1 = x1 ;
> this.y1 = y1 ;
> this.x2 = x2 ;
> this.y2 = y2 ;
> }
> }

> ////////////End of of DPanel.java

> ////////////Start of DClient.java
> import java.awt.* ;
> import javax.swing.* ;

>
> public class DClient extends JFrame {
> DClient ( String title ) {
> super ( title ) ;
> Container cp = getContentPane ( ) ;
> cp.add ( new DPanel ( true ) ) ;
>
> }
>
> public static void main ( String[] args ) {
> DClient dc = new DClient ( "Client" ) ;
> dc.setBounds ( 50, 50 , 200, 200 ) ;
> dc.show ( ) ;
> }

> }
> ////////////End of of DClient.java

> ////////////Start of DServer.java

> import java.io.* ;
> import java.awt.* ;
> import javax.swing.* ;
> import java.awt.event.* ;
> import java.net.* ;

> public class DServer extends JFrame {
> DPanel panel = new DPanel ( false ) ;
> JButton start = new JButton ( "Start Server" ) ;
>
> DServer ( String title ) {
> super ( title ) ;
> Container cp = getContentPane ( ) ;
> cp.add ( panel ) ;
> cp.add ( start, "North" ) ;
>
> //When button is clicked then start the server
> start.addActionListener (
> new ActionListener ( ) {
> public void actionPerformed ( ActionEvent e ) {
> try {
> ServerSocket s = new ServerSocket ( DPanel.PORT ) ;
> Socket connection = s.accept ( ) ;
> ObjectInputStream in = new ObjectInputStream ( connection.getInputStream ( ) ) ;
>
> while ( true ) {
> panel.setLine ( ( ALine ) in.readObject ( ) ) ;
>
> // If we call repaint ( ) then it doesn't work
> // If fact , we should read the new line coordinates
> // in a separate thread. This is ok for demo
> panel.paint ( panel.getGraphics ( ) ) ;
> }
>
> }
> catch ( Exception ex ) {
> System.out.println ( ex.getMessage ( ) ) ;
> }
> }
> }
> ) ;
>
> }
>
> public static void main ( String[] args ) {
> DServer dc = new DServer ( "Server" ) ;
> dc.setBounds ( 50, 50 , 200, 200 ) ;
> dc.show ( ) ;
> }

> }
> ////////////End of of DServer.java