package com.inet.html.samples;
import java.applet.Applet;
import java.awt.BorderLayout;
import java.net.URL;
import javax.swing.JFrame;
import javax.swing.WindowConstants;
import javax.swing.event.HyperlinkEvent;
import javax.swing.event.HyperlinkListener;
import com.inet.editor.BaseEditor;
import com.inet.editor.handler.HyperlinkHandler;
/**
* This sample demonstrates how to customize the {@link BaseEditor}s reaction on hyperlinks.
* The {@link BaseEditor} offers the possibility to register a handler instance to modify
* the internal {@link HyperlinkListener}.
* In this sample a handler will be created which restricts all actions on hyperlinks
* to the domain "localhost"
* @author i-net software GmbH
*/
public class HyperlinkHandlerSample extends Applet{
private static final String CONTENT =
"" +
"allowed localhost URL
" +
"allowed file URL
" +
"
" +
"forbidden external URL
" +
"forbidden external URL with IP
" +
"";
/**
* {@inheritDoc}
*/
@Override
public void init() {
super.init();
// we use the file editor sample here and modify it's hyperlink handler
FileEditor fileEditor = new FileEditor( null );
fileEditor.init();
modifyHandler( fileEditor.getEditor() );
this.setLayout( new BorderLayout() );
this.add( fileEditor, BorderLayout.CENTER );
}
/**
* Opens an editor frame
* @param args the command line arguments will be ignored here
*/
public static void main( String[] args ) {
JFrame frame = new JFrame();
frame.setLayout( new BorderLayout() );
frame.setDefaultCloseOperation( WindowConstants.EXIT_ON_CLOSE );
frame.setTitle( "JWebEngine hyperlink handler sample" );
// we use the file editor sample here and modify it's hyperlink handler
FileEditor fileEditor = new FileEditor( null );
fileEditor.init();
modifyHandler( fileEditor.getEditor() );
frame.add( fileEditor );
// NOTE: DO NOT PACK THE BaseEditor!
// The BaseEditor has a very small minimum size since it's toolbar is scalable. So, if you pack
// this component it will be minimized to the width of the smallest button.
frame.setSize( 800, 600 );
// display the component
frame.setVisible( true );
}
/**
* Sets the custom handler to a given {@link BaseEditor}
* @param baseEditor the {@link BaseEditor} to modify
*/
private static void modifyHandler( BaseEditor baseEditor ){
// now we set our handler
baseEditor.setCustomHyperlinkHandler( new Handler() );
// to show the effect of the handler we insert some content here
// NOTE: The editor will not display tooltips for forbidden locations as well here!
baseEditor.setText( CONTENT, true );
// this disables the toolbar and set the editor to not editable
baseEditor.setTextShowMode();
}
/**
* This is our {@link HyperlinkHandler} which will consume all events which point to an
* external location.
*/
private static class Handler implements HyperlinkHandler{
/**
* Checks if an URL will not redirect to any domain different do localhost
* @param url the URL to be checked
* @return true if the url is null or references to localhost
*/
private boolean allowAccess( URL url ){
return url == null || // no URL will cause no reaction on activate so it is allowed here
"localhost".equalsIgnoreCase( url.getHost() ) || // check for localhost domain
"file".equals( url.getProtocol() ); // files are on localhost as well!
}
/**
* {@inheritDoc}
*/
@Override
public boolean processActivated( HyperlinkEvent event ) {
// if the URL is NOT allowed we return true to mark the event as processed
URL url = event != null ? event.getURL() : null;
if( allowAccess( url) ){
return false;
} else {
System.err.println("ERROR: You are not allowed to open the location '" + url + "'" );
return true;
}
}
/**
* {@inheritDoc}
*/
@Override
public boolean processEntered( HyperlinkEvent event ) {
// if the URL is NOT allowed we return true to mark the event as processed
return !allowAccess( event != null ? event.getURL() : null);
}
/**
* {@inheritDoc}
*/
@Override
public boolean processExited( HyperlinkEvent event ) {
// if the URL is NOT allowed we return true to mark the event as processed
return !allowAccess( event != null ? event.getURL() : null);
}
}
}