Making an Applet Show a Document


You want an applet to transfer control to another web page.


Use the AppletContext method showDocument( ) .


Any applet can request the browser that contains it to show a new web page by passing the new URL into the showDocument( ) method. Usually, the browser replaces the current page with the target page. This, of course, triggers a call to the applet’s stop( ) method.

Note that the applet shown in Example 17-3 only works correctly in a full browser; the AppletViewer does not display HTML pages, so it ignores this method!

Example 17-3.

/** ShowDocApplet: Demonstrate showDocument(  ). 
public class ShowDocApplet extends Applet { 
    // String targetString = ""; 
    String targetString = "file:///c:/javasrc/network/"; 
    /** The URL to go to */ 
    URL targetURL; 
    /** Initialize the Applet */ 
    public void init(  ) { 
        try { 
            targetURL = new URL(targetString); 
        } catch (MalformedURLException mfu) { 
            throw new IllegalArgumentException( 
                "ShowDocApplet got bad URL " + targetString); 
        Button b = new Button("View Secret"); 
        b.addActionListener(new ActionListener(  ) { 
            public void actionPerformed(ActionEvent e) { 
                getAppletContext(  ).showDocument(targetURL); 
    public void stop(  ) { 
        System.out.println("Ack! Its been fun being an Applet. Goodbye!"); 

Figure 17-2 shows the program in operation.

Figure 17-2. ShowDocApplet program

If the ...

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