udpscreen.java

手机游戏设计一书的源代码

package net;

import  javax.microedition.lcdui.*;
import  javax.microedition.io.*;
import  java.io.*;

/**
*  MIDlet显示类
*/

public class UDPScreen extends Form
        implements CommandListener {

/**
*构造器
*/
    public UDPScreen (UDPMIDlet udpMIDlet) {
        super("Displayable Title");
        this.udpMIDlet = udpMIDlet;
        try {
            jbInit();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

/**
*  组件初始化
*/
    private void jbInit () throws Exception {

        // 设置当前对象为命令事件监听器
        setCommandListener(this);

        // 添加退出命令
        addCommand(new Command("Exit", Command.EXIT, 1));
        addCommand(new Command("Connect", Command.OK, 1));
    }

    class UDPConnector
            implements java.lang.Runnable {

        /**
         *  线程运行主方法
         */
        public void run () {
            connect();
        }
    }

    /**
     *  与UDP服务器通信的连接核心方法
     */
    public void connect () {
        Datagram revData = null;
        Datagram sendData = null;
        try {
            UDPDatagramConnection connection = (UDPDatagramConnection)Connector.open("datagram://jerrylin-w2kcn.sybase.com:5188");
            String clientMsg = "Hello Server!";
            sendData = connection.newDatagram(clientMsg.getBytes(), clientMsg.length());
            connection.send(sendData);
            revData = connection.newDatagram(connection.getMaximumLength());
            connection.receive(revData);
            connection.close();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
        TextBox input = new TextBox("Website content:", "", 50000, TextField.ANY);
        input.setTicker(new Ticker("connect internet"));
        input.setString(new String(revData.getData()));
        sendData = null;
        revData = null;
        Display.getDisplay(udpMIDlet).setCurrent(input);
    }

/**
*处理命令事件
*/
    public void commandAction (Command command, Displayable displayable) {

        if (command.getCommandType() == Command.EXIT) {
//退出MIDlet
UDPMIDlet.quitApp();
        }
        else if (command.getCommandType() == Command.OK) {
            new java.lang.Thread(new UDPConnector()).start();
        }
    }
    private UDPMIDlet udpMIDlet = null;
}