oaabrowser.java

SRI international 发布的OAA框架软件

/**
 *      @author Saidul M. Islam
 *      @note Modified from the Notepad example provided by Swing packages
 *      @date March 28, 1998
 *      
 *      This program will implement a subset of Web browser functionalities which can display only
 *      HTML 3.2 compatible html pages.
 *
 *      Modified and extended by Didier Guzzoni, SRI International
 **/

package com.sri.oaa2.guiutils; 

import java.awt.*;
import java.io.*;
import java.net.URL;

import javax.swing.text.*;
import javax.swing.event.*;
import javax.swing.*;


class OaaBrowser extends JPanel implements HyperlinkListener, Cloneable {
	private String homeURL = "http://www.ai.sri.com";
	private String docURL = homeURL;
  private JEditorPane mainBrowserPanel;

  private int MAX_HISTORY = 100;
  private String[] mHistory = new String[MAX_HISTORY];
  private int mHistoryIndex = -1;
  private int mHistorySize = 0;

	public OaaBrowser() {
		super(true);
		
		// Creates the main HTML panel
		mainBrowserPanel = new JEditorPane();
		mainBrowserPanel.setEditable(false);
		mainBrowserPanel.addHyperlinkListener(this);

		// Creates the Sroll Panel
		JScrollPane scroller = new JScrollPane();
		JViewport port = scroller.getViewport();
		port.add(mainBrowserPanel);

    // Main layout
    setLayout(new BorderLayout());
    add(scroller);
	}

	public void hyperlinkUpdate(HyperlinkEvent e) {
		if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED){
			setURL(e.getURL());
		}
	}
	
	public boolean setURL(String inUrl, boolean inUpdateHistory) {
		// DEBUG
		//System.out.println("Loading " + inUrl);
		Document currentDocument = mainBrowserPanel.getDocument();
		try {
			mainBrowserPanel.setPage(inUrl);
			if (inUpdateHistory) {
        mHistoryIndex = (mHistoryIndex+1)%MAX_HISTORY;
        mHistory[mHistoryIndex]=inUrl;
		    mHistorySize++;
			}
			return true;
		} 
		catch (IOException ioe) {
			mainBrowserPanel.setDocument(currentDocument);
			System.out.println("Could not load URL");
			return false;
		} 
	}
	
	public boolean setURL(URL inUrl, boolean inUpdateHistory) {
		return setURL(inUrl.toString());
	}

	public boolean setURL(URL inUrl) {
		return setURL(inUrl, true);
	}

	public boolean setURL(String inUrl) {
		return setURL(inUrl, true);
	}

	public boolean back(){
		// Updates the index within the history
		if ((mHistoryIndex<0) || 
		    ((mHistoryIndex==0) && (mHistoryIndex<MAX_HISTORY)))
		  return false;
    mHistoryIndex--;
    if (mHistoryIndex < 0)
      mHistoryIndex = MAX_HISTORY;
    return setURL(mHistory[mHistoryIndex], false);
	}
	
	public boolean forward(){	
		// Updates the index within the history
		if ((mHistoryIndex<0) || ((mHistoryIndex+1)==mHistorySize))
		  return false;
    mHistoryIndex = (mHistoryIndex+1)%MAX_HISTORY;
    return setURL(mHistory[mHistoryIndex], false);
	}
}