J2ME做无线智能终端，举个例，写段代码

以下是一个简单的 J2ME 代码示例，演示了如何使用 J2ME 编写一个无线智能终端：

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

public class WirelessClient extends MIDlet implements CommandListener {
    private static final String SERVER_URL = "socket://192.168.0.1:9999"; // 服务器地址和端口号
    private Display display;
    private Form mainForm;
    private Command exitCommand;
    private Command sendCommand;
    private TextField messageField;
    private StringItem responseItem;
    private SocketConnection socketConnection;
    private InputStream inputStream;
    private OutputStream outputStream;

    public void startApp() {
        // 创建显示器
        display = Display.getDisplay(this);

        // 创建主界面
        mainForm = new Form("Wireless Client");

        // 创建消息输入框和发送按钮
        messageField = new TextField("Message", "", 100, TextField.ANY);
        sendCommand = new Command("Send", Command.OK, 0);
        mainForm.append(messageField);
        mainForm.addCommand(sendCommand);

        // 创建响应结果显示区域和退出按钮
        responseItem = new StringItem("", "");
        exitCommand = new Command("Exit", Command.EXIT, 0);
        mainForm.append(responseItem);
        mainForm.addCommand(exitCommand);

        // 显示主界面
        display.setCurrent(mainForm);

        // 建立与服务器的连接
        try {
            socketConnection = (SocketConnection) Connector.open(SERVER_URL);
            inputStream = socketConnection.openInputStream();
            outputStream = socketConnection.openOutputStream();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void pauseApp() {}

    public void destroyApp(boolean unconditional) {
        // 关闭与服务器的连接
        try {
            inputStream.close();
            outputStream.close();
            socketConnection.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void commandAction(Command command, Displayable displayable) {
        if (command == exitCommand) {
            // 退出应用程序
            destroyApp(true);
            notifyDestroyed();
        } else if (command == sendCommand) {
            // 发送消息给服务器
            String message = messageField.getString();
            try {
                outputStream.write(message.getBytes());
                outputStream.flush();

                // 读取服务器响应
                byte[] buffer = new byte[1024];
                int len = inputStream.read(buffer);
                if (len != -1) {
                    String response = new String(buffer, 0, len);
                    responseItem.setText(response);
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

这个示例代码实现了一个简单的 J2ME 客户端，该客户端连接到指定的服务器地址和端口号，并可以发送消息到服务器并接收服务器的响应。具体的协议内容处理部分需要根据实际应用情况进行编写。