readfromhttpserver.java

《Java ME手机应用开发大全》源码 書籍內容簡介： http://www.china-pub.com/410

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import java.io.*;
import javax.microedition.io.*;
import java.util.*;
public class ReadFromHTTPServer extends MIDlet implements CommandListener
{ 
   private Command exitCommand,nextCommand;
   private Display display;
   private Form form;
   private StringItem keyWord;
   private byte[] b;
   
   public ReadFromHTTPServer()
   {
    display = Display.getDisplay(this);
    exitCommand = new Command("Exit",Command.EXIT,2);
    nextCommand = new Command("Next",Command.OK,2);
    form = new Form("Online Novel");
    keyWord = new StringItem(" "," ");
    Ticker ticker = new Ticker("Download Novel");
    form.setTicker(ticker);
    form.append(keyWord);
    form.addCommand(exitCommand);
    form.addCommand(nextCommand);
    form.setCommandListener(this);
   }

  public void startApp() throws MIDletStateChangeException
  {
   display.setCurrent(form);
   readKeyword();
   showKeyword();
  }
  public void pauseApp(){}
  public void destroyApp(boolean unconditional){}
  public void commandAction(Command c, Displayable d)
  {
   if(c==exitCommand)
   {
    destroyApp(false);
    notifyDestroyed();
   }
   else if(c==nextCommand)
   {
    showKeyword();
   }
  }
  private void readKeyword()
  {
   HttpConnection connect = null;
   InputStream inStream = null;
   ByteArrayOutputStream baos=new ByteArrayOutputStream();
   
   try
      {
	   //建立并打开HTTP连接
       connect = (HttpConnection)Connector.open("http://localhost:8080/note.txt");
	   //获得连接的输入流
       inStream = connect.openInputStream();
       int input;
	   //通过输入流读取服务器上文件
       while ((input=inStream.read())!= -1)
       {
        
		 baos.write(input);
       
       }
	   //将读取的内容转化为字节数组
	   b=baos.toByteArray();
      }
      
   catch(IOException e)
   {
    System.err.println(" the connection could not be established. sorry for the inconvenience");
   }
  }
  private void showKeyword()
  {
	  try
	  {
		  //将读取的文件内容转换为中文格式并显示出来
         keyWord.setText(new String(b,"gb2312"));
	  }
	  catch(Exception e)
	  {
	  }
   
  }
}