socketclient.java

登陆用的源程序~~~不怎么样``但也是我初学的参考的有用的资料

package socket;
import javax.microedition.midlet.*;
import javax.microedition.io.*;
import javax.microedition.lcdui.*;
import java.io.*;
public class SocketClient extends MIDlet implements Runnable, CommandListener {
    private Display display;
    private Form f;
    private TextField tf;		// 用于输入要发送的字符串
    private StringItem si;		// 用于显示接收到的字符串
    private Command sendCommand = new Command("Send", Command.ITEM, 1);
    private Command exitCommand = new Command("Exit", Command.EXIT, 1);
    SocketConnection sc;		// 套接字连接
    InputStream is;				// 输入流
    OutputStream os;			// 输出流
    Sender sender;				// 用于发送数据的线程
	public SocketClient() {
        display = Display.getDisplay(this);
        f = new Form("Socket Client");
        tf = new TextField("发送:", "", 30, TextField.ANY);
        si = new StringItem("状态:", " ");
        f.append(tf);
        f.append(si);
        f.addCommand(exitCommand);
        f.addCommand(sendCommand);
        f.setCommandListener(this);
        display.setCurrent(f);
	}
    public void startApp() {
        new Thread(this).start();	// 开始客户端连接的线程
    }
    public void run() {
        try {
			// 客户端套接字，连接到主机localhost的5000端口
            sc = (SocketConnection) Connector.open("socket://localhost:5000");
            si.setText("连接到服务器");		// 设置当前显示的状态
            is = sc.openInputStream();		// 打开输入流
            os = sc.openOutputStream();		// 打开输出流
            sender = new Sender(os);		// 建立线程，用于发送数据
            while (true) {			// 永久循环，用于接收数据并显示
                StringBuffer sb = new StringBuffer();
                int c = 0;
                while (((c = is.read()) != '\n') && (c != -1)) {
                    sb.append((char) c);
                }
                if (c == -1) break;		// 输入流关闭，跳出循环
                si.setText("接收到消息 - " + sb.toString());	// 显示收到的数据
            }
            stop();						// 关闭输入/输出流和Socket连接
            si.setText("连接关闭");		// 设置当前显示的状态
            f.removeCommand(sendCommand);
        } catch (ConnectionNotFoundException e) {
			System.out.println("错误：请先运行服务器端");
            destroyApp(true);
            notifyDestroyed();
        } catch (Exception e) {
			System.out.println("错误："+e.getMessage());
        }
    }
    public void pauseApp() { }
    public void destroyApp(boolean unconditional) {
		stop();
    }
    public void commandAction(Command c, Displayable s) {
        if (c == exitCommand) {
            destroyApp(true);
            notifyDestroyed();
        } if (c == sendCommand) {
            sender.send(tf.getString());	// 将输入的字符串发送
        }
    }
    // 关闭输入/输出流和Socket连接
    public void stop() {
        try {
            if (sender != null) sender.stop();
            if (is != null) is.close();
            if (os != null) os.close();
            if (sc != null) sc.close();
        } catch (IOException ioe) {}
    }
}