e694. reading an image from a file, inputstream, or url.txt

这里面包含了一百多个JAVA源文件

This example demonstrates how to use the javax.imageio package to read an image from a file, input stream, or URL. The example also demonstrates how to display the image on the screen. 
GIF, PNG, and JPEG formats are supported by the javax.imageio package by default. 

This example works only in J2SE 1.4. For a method that works since J2SE 1.3, see e594 Reading an Image or Icon from a File. 

    Image image = null;
    try {
        // Read from a file
        File file = new File("image.gif");
        image = ImageIO.read(file);
    
        // Read from an input stream
        InputStream is = new BufferedInputStream(
            new FileInputStream("image.gif"));
        image = ImageIO.read(is);
    
        // Read from a URL
        URL url = new URL("http://hostname.com/image.gif");
        image = ImageIO.read(url);
    } catch (IOException e) {
    }
    
    // Use a label to display the image
    JFrame frame = new JFrame();
    JLabel label = new JLabel(new ImageIcon(image));
    frame.getContentPane().add(label, BorderLayout.CENTER);
    frame.pack();
    frame.setVisible(true);