graphicsdemo.java

精通Java核心技术源代码

import java.awt.*;	
import javax.swing.*;

public class GraphicsDemo extends JFrame 
{
      	public GraphicsDemo() 
      	{
      		super( "GraphicsDemo" );
    	
      		setSize( 400,180 );
			setVisible( true );
      	}
     
      	public void paint( Graphics g )
      	{
      		// 调用父类的 paint方法 
      		super.paint( g );
    	
      		g.setColor( Color.red );
      		g.drawLine( 20,35,108,90 );
      		g.drawString( "Welcome to Java!",20,135 );
    	
    		g.setColor( Color.green );
    		g.drawRect( 138,35,100,55 );
    		g.fillRect( 138,100,100,55 );
    	
    		g.setColor( Color.blue );
    		g.drawOval( 268,35,100,55 );
     		g.fillOval( 268,100,100,55 );
       	}
    
       	public static void main(String[] args) 
       	{
          	GraphicsDemo graphicsDemo = new GraphicsDemo();
          	graphicsDemo.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
       	}
}