internetaccess.java

这是java的基础知识的课件

//InternetAccess.java

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

public class InternetAccess
{  
	public static void main(String[] args)
	{  
		ImageFrame frame = new ImageFrame();
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.show();
	}
}

class ImageFrame extends JFrame
{
	public static final int WIDTH = 300;
	public static final int HEIGHT = 120;  

	public ImageFrame()
	{
		setTitle("InternetAccess");
		setSize(WIDTH, HEIGHT);

		ImagePanel panel = new ImagePanel();
		Container contentPane = getContentPane();
		contentPane.add(panel);
	}
}

class ImagePanel extends JPanel
{  
	private Image image;
	URL url;
	
	public ImagePanel()
	{  
		try
		{
//指定要获取的资源的URL。
			url = new URL(
				"http://www.waterpub.com.cn/images/cwpp_logo1.gif");
		}
		catch ( MalformedURLException e)
		{
		}
//获取指定URL上的图像。
		image = Toolkit.getDefaultToolkit().getImage(url);
	}

	public void paintComponent(Graphics g)
	{  
		super.paintComponent(g);
	
		int imageWidth = image.getWidth(this);
		int imageHeight = image.getHeight(this);

//	在窗口中显示图像。
		g.drawImage(image, 0, 0, null);
//显示字符串。
		g.drawString("正在下载图像...", 100, 80);
	}
}