J2ME应用程序架构模型

/**View:Display messsage, Receive input*/
package view;
import.....
public class view extends Canvas
{
public String getUserName();
public String getUserPassword();
public void displayMessage(Graphics g)
{    
g.drawString(Handler.getInstance().getMessageContent(),x,y,0);
}
public void commandAction(Command c,Displayable d)
{
Handler.getInstance().setUserInfo(getUserName(),getUserPassword());
}
}
/**************************************/
/*Handler:Control network message*/
package handler;
import......
public class Handler
{
public sendUserInfo(String name,String password);
public void getResponse()
{
if(ok)
{
notfiyDisplay();
}
}
public void notfiyDisplay()
{
Message mess = new Message( mess.toString() ) ;
Database.putMessage( mess )

View.getInstance().repaint();    
}
public String getMessageContent()
{
Message m = Database.getInstance.getMessage();
return m.getContent();
}
}
/************************************/
/*Message: a model indicate message object*/
package model;
import......
public class Message
{
public Message(String str)
{
}
public String getContent()
{
} 
}
/**********************************/
/*Database: store bytes*/
package database;
import......
public Database
{
public void putMessage(Message mess)
{
}
public Message getMessage()
{
}
}
/***********************************/