Java ME 開啟Socket串連示範

/*
 * ScoketClient.java 
 */
package mypackage;

import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.TextBox;
import javax.microedition.lcdui.TextField;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;

import mypackage.SocketBot;

/**
 * socket commucation midlet
 * 
 * @author 
 * 
 */
public class SocketClient extends MIDlet implements CommandListener {

private static final String TITLE = "Socket Test";

private static final String SOCKET_URL = "socket_url";

private TextBox textBox;

private Command exitCommand;

public SocketClient() {
                initUI();
        }

protected void destroyApp(boolean unconditional) {
// empty

        }

protected void pauseApp() {
// empty

        }

protected void startApp() throws MIDletStateChangeException {
                Display.getDisplay(this).setCurrent(textBox);

        }

private void initUI() {
                String url = this.getAppProperty(SOCKET_URL);
                SocketBot soc = new SocketBot(url);
                soc.send();
                String content = soc.retrieveLog();

                textBox = new TextBox(TITLE, content, 1024, TextField.ANY);

                exitCommand = new Command("Exit", Command.EXIT, 0);
                textBox.addCommand(exitCommand);
                textBox.setCommandListener(this);

        }

public void commandAction(Command arg0, Displayable arg1) {
this.destroyApp(false);
super.notifyDestroyed();
        }

}

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

/*
 * SocketBot.java Sep 21, 2006
 */
package mypackage;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.microedition.io.Connector;
import javax.microedition.io.SocketConnection;

/**
 * do socket connection things
 * 
 * @author
 * 
 */
public class SocketBot {

private static final String HELLO = "hello";

private static final String CRLF = "/r/n";

private static final String SEND = ">>", RECV = "<<";

private String url;

private StringBuffer sb;

public SocketBot(String newUrl) {
this.url = newUrl;
                sb = new StringBuffer();
        }

/**
         * send and recieve some data
         */
public void send() {
                SocketConnection conn;
// open connection goes here
try {
                        conn = (SocketConnection) Connector.open(url);
                } catch (IOException e) {
                        sb.append(e.toString());
return;
                }
try {
                        conn.setSocketOption(SocketConnection.DELAY, 0);
                        InputStream recvStream = conn.openInputStream();
                        OutputStream sendStream = conn.openOutputStream();
// write something
                        sendStream.write(HELLO.getBytes());
                        sendStream.write(CRLF.getBytes());
// append send data to log
                        sb.append(SEND).append(HELLO).append(CRLF);
// begin to read
                        StringBuffer sbuf = new StringBuffer();
int c = 0;
while ((c = recvStream.read()) != -1) {
                                sbuf.append((char) c);
                        }
// put to log
                        sb.append(RECV).append(sbuf.toString()).append(CRLF);
// close input stream and output stream when done
                        recvStream.close();
                        sendStream.close();
// append exception to log if any
                } catch (IllegalArgumentException e) {
                        sb.append(e.toString());
                } catch (IOException e) {
                        sb.append(e.toString());
                } finally {
// do not forget to close the connection for re-use
try {
                                conn.close();
                        } catch (IOException ignored) {
// should be ignored
                        }

                }

        }

/**
         * retreive the result log
         * 
         * @return
         */
public String retrieveLog() {
return sb.toString();
        }

}