client.java

非富多彩的十六个J2ME的例子

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.io.*;
import java.io.*;
public class client extends MIDlet implements CommandListener
{
   Display dis;
   Form frm;
   Command cmdexit,cmdok,cmdsent,cmdback;
   StringItem str;
   List menu;
   TextBox tb;
   
   
   
   public client()
   {
   	  cmdexit=new Command("Exit",Command.EXIT,1);
      cmdok=new Command("Ok",Command.OK,0);
      cmdsent=new Command("Sent",Command.OK,2);
      cmdback=new Command("Back",Command.BACK,3);
   	  dis=Display.getDisplay(this);
   	  String menuItem[]={"Current Balance","Fixed Deposit","Cheque Status"};
   	  menu=new List("SMMB",List.IMPLICIT,menuItem,null);
   	  menu.addCommand(cmdexit);
   	  menu.addCommand(cmdok);
   	  menu.setCommandListener(this);
   	  
   	  
   	  tb=new TextBox("Enter your PIN",null,30,TextField.NUMERIC);
   	  str=new StringItem("PIN","");
   	  tb.addCommand(cmdexit);
   	  tb.addCommand(cmdsent);
   	  tb.setCommandListener(this);
   	  
   	   frm=new Form("Status");
   	   str=new StringItem("Status","");
   	   frm.append(str);
   	   frm.addCommand(cmdback);
   	   frm.addCommand(cmdok);
   	   frm.setCommandListener(this);
   	   
   	
   }
   
   public void startApp() 
   {
   	  dis.setCurrent(menu);
   	  	
   	 
   }
   
   public void pauseApp()
   {
   	
   }
   
   public void destroyApp(boolean b)
   {
   	
   	   notifyDestroyed();
   }
   
   public void commandAction(Command c,Displayable b)
   {
   	    if(c==cmdexit)
   	      destroyApp(true);
   	    else if(c==cmdback)
   	    {
   	       dis.setCurrent(menu);	
   	    } 
   	    
   	    else if(c==cmdok)
   	    {
   	       dis.setCurrent(tb);	
   	    } 
   	    
   	    else if(c==cmdsent)
   	    {
   	       String pin=tb.getString();
   	       String balance;
   	       balance=getBalance(pin);
   	       dis.setCurrent(frm);	
   	       str.setText(balance);
   	    }	
   }
   
   public String getBalance(String pin);
   {
	 byte[] data;
	 String url="http:localhost:8000/";
	 try
	 {
	    HttpConnection hc=(HttpConnection)Connector.open(url);
	    ByteArrayOutputStream bs=new ByteArrayOutputStream();
	    DataOutputStream ds=new DataOutputStream(bs);
	    ds.writeUTF(pin);
	    ds=bs.toByteArray();
	    hc.setRequestMethod(hc.POST);
	    hc.setRequestProperty("Content-Length",Integer.toString(data.length));
	    OutputStream os=hc.openOutputStream();
	    os.write(data);
	    os.close();
	    int readcode=hc.getResponseCode();
	    if(readcode==hc.HTTP_OK)
	    {
	    	
				DataInputStream di=new DataInputStream(hc.openDataInputStream());
				String balance = di.readUTF();
				return balance;
	    }
	    	else
				return "Error";
	 
	 }
	 
	 catch(Exception e)
	 {
	    	System.out.println(e);
			return "Error";	
	 }
	
   }	
	
}