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QuoteClientApplet.javaAPI DocExample4275Tue Dec 12 18:57:28 GMT 2000None

QuoteClientApplet

public class QuoteClientApplet extends Applet implements ActionListener

Fields Summary
boolean
DEBUG
InetAddress
address
TextField
portField
Label
display
DatagramSocket
socket
Constructors Summary
Methods Summary
public voidactionPerformed(java.awt.event.ActionEvent event)

        int port;
        
        try {
            port = Integer.parseInt(portField.getText());
            doIt(port);
        } catch (NumberFormatException e) {
            //No integer entered.  Should warn the user.
        }
voiddoIt(int port)

        DatagramPacket packet;
        byte[] sendBuf = new byte[256];
        
        packet = new DatagramPacket(sendBuf, 256, address, port);

        try { // send request
            if (DEBUG) {
                System.out.println("Applet about to send packet to address "
                               + address + " at port " + port);
            }
            socket.send(packet);
            if (DEBUG) {
                System.out.println("Applet sent packet.");
            }
        } catch (IOException e) {
            System.out.println("Applet socket.send failed:");
            e.printStackTrace();
            return;
        }

        packet = new DatagramPacket(sendBuf, 256);

        try { // get response
            if (DEBUG) {
                System.out.println("Applet about to call socket.receive().");
            }
            socket.receive(packet);
            if (DEBUG) {
                System.out.println("Applet returned from socket.receive().");
            }
        } catch (IOException e) {
            System.out.println("Applet socket.receive failed:");
            e.printStackTrace();
            return;
        }

        String received = new String(packet.getData());
        if (DEBUG) {
            System.out.println("Quote of the Moment: " + received);
        }
        display.setText(received);
public java.awt.InsetsgetInsets()

        return new Insets(4,4,5,5);
public voidinit()


       
        //Initialize networking stuff.
        String host = getCodeBase().getHost();

        try {
            address = InetAddress.getByName(host);
        } catch (UnknownHostException e) {
            System.out.println("Couldn't get Internet address: Unknown host");
            // What should we do?
        }

        try {
            socket = new DatagramSocket();
        } catch (IOException e) {
            System.out.println("Couldn't create new DatagramSocket");
            return;
        }

        //Set up the UI.
        GridBagLayout gridBag = new GridBagLayout();
        GridBagConstraints c = new GridBagConstraints();
        setLayout(gridBag);

        Label l1 = new Label("Quote of the Moment:", Label.CENTER);
        c.anchor = GridBagConstraints.SOUTH;
        c.gridwidth = GridBagConstraints.REMAINDER;
        gridBag.setConstraints(l1, c); 
        add(l1);

        display = new Label("(no quote received yet)", Label.CENTER);
        c.anchor = GridBagConstraints.NORTH;
        c.weightx = 1.0;
        c.fill = GridBagConstraints.HORIZONTAL;
        gridBag.setConstraints(display, c); 
        add(display);

        Label l2 = new Label("Enter the port (on host " + host
                             + ") to send the request to:", 
                             Label.RIGHT);
        c.anchor = GridBagConstraints.SOUTH;
        c.gridwidth = 1;
        c.weightx = 0.0;
        c.weighty = 1.0;
        c.fill = GridBagConstraints.NONE;
        gridBag.setConstraints(l2, c); 
        add(l2);

        portField = new TextField(6);
        gridBag.setConstraints(portField, c); 
        add(portField);

        Button button = new Button("Send");
        gridBag.setConstraints(button, c); 
        add(button);

        portField.addActionListener(this);
        button.addActionListener(this);
public voidpaint(java.awt.Graphics g)

        Dimension d = getSize();
        Color bg = getBackground();

        g.setColor(bg);
        g.draw3DRect(0, 0, d.width - 1, d.height - 1, true);
        g.draw3DRect(3, 3, d.width - 7, d.height - 7, false);