java.fedora.swing.jhelp.SimpleContentViewerUI Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of fcrepo-client Show documentation
The Fedora Client is a Java Library that allows API access to a Fedora Repository. The client is typically one part of a full Fedora installation.
The newest version!
/*
 * -----------------------------------------------------------------------------
 *
 * License and Copyright: The contents of this file are subject to the
 * Apache License, Version 2.0 (the "License"); you may not use 
 * this file except in compliance with the License. You may obtain a copy of 
 * the License at 
 * http://www.fedora-commons.org/licenses.
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
 * the specific language governing rights and limitations under the License.
 *
 * The entire file consists of original code.
 * Copyright © 2008 Fedora Commons, Inc.

 * 
Copyright © 2002-2007 The Rector and Visitors of the University of 
 * Virginia and Cornell University
 
 * All rights reserved.
 *
 * -----------------------------------------------------------------------------
 */
package fedora.swing.jhelp;

import javax.help.*;
import javax.help.plaf.HelpContentViewerUI;
import javax.help.event.*;
import java.util.Hashtable;
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.text.html.HTMLEditorKit;
import javax.swing.text.html.StyleSheet;
import javax.swing.plaf.ComponentUI;
import javax.swing.border.*;
import javax.swing.event.*;
import javax.swing.text.html.HTMLFrameHyperlinkEvent;
import javax.swing.text.html.HTMLDocument;
import java.awt.*;
import java.net.URL;
import java.net.MalformedURLException;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.io.*;
import javax.help.Map.ID;

/**
 * 
 * Title: SimpleContentViewerUI.java
 * 
 * 
 * Description: Based on SimpleContentViewerUI in javax.help.plaf.basic,
 * which comes with JavaHelp, which comes with Java1.4, and is written by Sun
 * Microsystems. More information on JavaHelp can be found at
 * http://java.sun.com/products/javahelp/faq.html
 * 
 * But this version doesn't call setBackingStoreEnable(true),
 * which is a deprecated method (as of java1.4) anyway.
 * 

 * This simple modification has the net effect of allowing images displayed in
 * help content windows to not be mangled (actually, they mysteriously
 * disappear) when the scrollbar is first used.
 * 

 * 
 * -----------------------------------------------------------------------------
 * 
 * Portions created by Sun Microsystems are Copyright © Sun Microsystems,
 * originally made available at java.sun.com
 * 
 * 
 * -----------------------------------------------------------------------------
 * 
 * @author Sun Microsystems, [email protected]
 * @version $Id: SimpleContentViewerUI.java 5162 2006-10-25 00:49:06Z eddie $
 */

public class SimpleContentViewerUI extends HelpContentViewerUI implements
		HelpModelListener, TextHelpModelListener, HyperlinkListener,
		PropertyChangeListener, Serializable {
	private static final long serialVersionUID = 1L;

	// Suggestion: Refactor the class and remove the menu bar and the
	// HTML viewer into subclasses. This would allow easier
	// replacement of both components to
	//
	// cwilper:note ^^^ haha, looks like they were thinking about making
	// replacement easier at some point... ahh well.
	protected JHelpContentViewer theViewer;

	private static Dimension PREF_SIZE = new Dimension(200, 300);

	private static Dimension MIN_SIZE = new Dimension(80, 80);

	private JEditorPane html;

	private JViewport vp;

	private Hashtable registry;

	private boolean loadingURL;

	private TextHelpModelEvent pendingHighlightsEvent;

	public static ComponentUI createUI(JComponent x) {
		debug("createUI");
		return new SimpleContentViewerUI((JHelpContentViewer) x);
	}

	public SimpleContentViewerUI(JHelpContentViewer b) {
		debug("createUI - sort of");
	}

	public void setEditorKit(String type, EditorKit kit) {
		debug("setEditorKit(" + type + ", " + kit + ")");
		if (registry == null) {
			registry = new Hashtable(3);
		}
		registry.put(type, kit);
		if (html != null) {
			debug("  type: " + type);
			debug("  kit: " + kit);
			html.setEditorKitForContentType(type, kit);
			if (debug)
				debug("  kit got: " + html.getEditorKitForContentType(type));
		}
	}

	/**
	 * Subclass of JEditorPane that uses the JHelpContentViewer type registry.
	 */

	public class JHEditorPane extends JEditorPane {
		private static final long serialVersionUID = 1L;

		private Hashtable typeHandlers;

		public EditorKit getEditorKitForContentType(String type) {
			if (typeHandlers == null) {
				typeHandlers = new Hashtable(3);
			}
			EditorKit k = (EditorKit) typeHandlers.get(type);
			if (k == null) {
				k = theViewer.createEditorKitForContentType(type);
				if (k != null) {
					setEditorKitForContentType(type, k);
					typeHandlers.put(type, k);
				}
			}
			if (k == null) {
				k = super.getEditorKitForContentType(type);
				if (k != null) {
					typeHandlers.put(type, k);
				}
			}
			return k;
		}

	}

	public void installUI(JComponent c) {
		debug("installUI");
		theViewer = (JHelpContentViewer) c;
		theViewer.setLayout(new BorderLayout());

		// listen to property changes...
		theViewer.addPropertyChangeListener(this);

		TextHelpModel model = theViewer.getModel();
		if (model != null) {
			// listen to id changes...
			model.addHelpModelListener(this);
			// listen to highlight changes...
			model.addTextHelpModelListener(this);
		}

		html = new JHEditorPane();
		html.addPropertyChangeListener(this);

		html.setEditable(false);
		html.addHyperlinkListener(this);
		JScrollPane scroller = new JScrollPane();
		scroller.setBorder(new BevelBorder(BevelBorder.LOWERED, Color.white,
				Color.gray));
		vp = scroller.getViewport();
		vp.add(html);

		// here is the suspect line:
		//
		// Interesting fact: It took about eight hours to come up with
		// a solution which incorporated removal of this line while
		// keeping the base javahelp classes intact, and dealing with
		// miscellaneous errors that came up.
		//
		// But I won, see. I won. That's all that matters,
		// mister computer. Bite me!! nyeh nyeh!!!!
		//
		// vp.setBackingStoreEnabled(true);

		theViewer.add("Center", scroller);
		loadingURL = false;
		pendingHighlightsEvent = null;
	}

	public void uninstallUI(JComponent c) {
		debug("uninstallUI");
		JHelpContentViewer viewer = (JHelpContentViewer) c;
		viewer.removePropertyChangeListener(this);
		html.removePropertyChangeListener(this);
		TextHelpModel model = viewer.getModel();
		if (model != null) {
			model.removeHelpModelListener(this);
			model.removeTextHelpModelListener(this);
		}
		viewer.setLayout(null);
		viewer.removeAll();
	}

	public Dimension getPreferredSize(JComponent c) {
		return PREF_SIZE;
	}

	public Dimension getMinimumSize(JComponent c) {
		return MIN_SIZE;
	}

	public Dimension getMaximumSize(JComponent c) {
		// This doesn't seem right. But I'm not sure what to do for now
		return new Dimension(Integer.MAX_VALUE, Integer.MAX_VALUE);
	}

	public void idChanged(HelpModelEvent e) {
		ID id = e.getID();
		URL url = e.getURL();
		TextHelpModel model = theViewer.getModel();
		debug("idChanged(" + e + ")");
		debug("  = " + id + "--" + url);
		debug("  my helpModel: " + model);

		model.setDocumentTitle(null);

		// HERE - REMIND - event should be generated after visit
		// with the title already in there - epll.
		try {
			Highlighter h = html.getHighlighter();
			debug("removeAllHighlights");
			h.removeAllHighlights();
			try {
				loadingURL = true;
				html.setPage(url);
			} catch (Exception ex) {
				loadingURL = false;
				// IGNORE FOR EA2 --- !! - epll
			}
			debug("html current EditorKit is: " + html.getEditorKit());
			debug("html current ContentType is: " + html.getContentType());
		} catch (Exception e3) {
			// e.g. and incorrect URL will generate a nullexception!!
			// ignore
			debug("Exception geneartated");
		}
		debug("done with idChanged");
	}

	private void rebuild() {
		debug("rebuild");
		TextHelpModel model = theViewer.getModel();
		if (model == null) {
			debug("rebuild-end: model is null");
			return;
		}
		// The model has changed. I'll need to clear the HTML viewer and
		// put in the home page
		Highlighter h = html.getHighlighter();
		debug("removeAllHighlights");
		h.removeAllHighlights();
		HelpSet hs = model.getHelpSet();
		try {
			ID id = hs.getHomeID();
			model.setCurrentID(id);
		} catch (Exception e) {
			// ignore
		}
		debug("rebuld-end");
	}

	public void propertyChange(PropertyChangeEvent event) {
		debug("propertyChange: " + event.getPropertyName() + "\n\toldValue:"
				+ event.getOldValue() + "\n\tnewValue:" + event.getNewValue());

		if (event.getSource() == theViewer) {
			String changeName = event.getPropertyName();
			if (changeName.equals("helpModel")) {
				TextHelpModel oldModel = (TextHelpModel) event.getOldValue();
				TextHelpModel newModel = (TextHelpModel) event.getNewValue();
				if (oldModel != null) {
					oldModel.removeHelpModelListener(this);
					oldModel.removeTextHelpModelListener(this);
				}
				if (newModel != null) {
					newModel.addHelpModelListener(this);
					newModel.addTextHelpModelListener(this);
				}
				rebuild();
			} else if (changeName.equals("font")) {
				debug("font changed");
				Font newFont = (Font) event.getNewValue();
				EditorKit ek = html.getEditorKit();
				if (ek instanceof HTMLEditorKit) {
					String cssData = "body { font-family: "
							+ newFont.getFamily() + " }";
					HTMLEditorKit hek = (HTMLEditorKit) ek;
					StyleSheet styles = hek.getStyleSheet();
					try {
						styles.loadRules(new StringReader(cssData), null);
					} catch (Exception ex) {
					}
				}
				RepaintManager.currentManager(html).markCompletelyDirty(html);
			}
		} else if (event.getSource() == html) {
			String changeName = event.getPropertyName();
			if (changeName.equals("page")) {
				debug("page finished loading");
				loadingURL = false;
				if (pendingHighlightsEvent != null) {
					debug("Loading the highlights now");
					highlightsChanged(pendingHighlightsEvent);
					pendingHighlightsEvent = null;
				}
				Document doc = html.getDocument();
				String title = (String) doc.getProperty(Document.TitleProperty);
				TextHelpModel model = theViewer.getModel();
				model.setDocumentTitle(title);

				// Propogate this to property listeners of the ContentViewer.
				// Can't acutally send the real thing because Objects and
				// Strings aren't supported.
				theViewer.firePropertyChange(event.getPropertyName(), false,
						true);
			}
		}
	}

	/**
	 * Notification of a change relative to a hyperlink.
	 */
	public void hyperlinkUpdate(HyperlinkEvent e) {
		if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED) {
			// If in a frame do something different
			if (e instanceof HTMLFrameHyperlinkEvent) {
				((HTMLDocument) html.getDocument())
						.processHTMLFrameHyperlinkEvent((HTMLFrameHyperlinkEvent) e);
			} else {
				// Not a frame
				linkActivated(e.getURL());
			}
		}
	}

	/**
	 * Follows the reference in an link. The given url is the requested
	 * reference. By default this calls setPage, and if
	 * an exception is thrown the original previous document is restored and a
	 * beep sounded. If an attempt was made to follow a link, but it represented
	 * a malformed url, this method will be called with a null argument.
	 * 
	 * @param u
	 *            the URL to follow
	 */
	protected void linkActivated(URL u) {
		debug("linkActivated - URL=" + u);
		Cursor c = html.getCursor();
		Cursor waitCursor = Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR);
		html.setCursor(waitCursor);
		// workaround for bug #418959
		// if there is an anchor make sure the file doesn't end in "/" or "\"
		// if it does then get the current file name and append the ref
		String ref = u.getRef();
		if (ref != null) {
			String file = u.getFile();
			if (file.endsWith("/") || file.endsWith("\\")) {
				u = html.getPage();
				debug("current u=" + u);
				file = u.getFile();
				debug("file=" + file);
				try {
					u = new URL(u.getProtocol(), u.getHost(), u.getPort(), file
							+ "#" + ref);
				} catch (MalformedURLException e2) {
					return;
				}
				debug("new u=" + u);
			}
		}
		SwingUtilities.invokeLater(new PageLoader(u, c));
	}

	/**
	 * Temporary class that loads synchronously (although later than the request
	 * so that a cursor change can be done).
	 */
	class PageLoader implements Runnable {

		PageLoader(URL u, Cursor c) {
			url = u;
			cursor = c;
		}

		public void run() {
			if (url == null) {
				// restore the original cursor
				html.setCursor(cursor);

				RepaintManager.currentManager(html).markCompletelyDirty(html);
			} else {
				Document doc = html.getDocument();
				String title;
				try {
					html.setPage(url);
					loadingURL = true;
					doc = html.getDocument();
					title = (String) doc.getProperty(Document.TitleProperty);

					TextHelpModel model = theViewer.getModel();
					model.setDocumentTitle(title);
					ID id = model.getHelpSet().getCombinedMap().getIDFromURL(
							url);
					if (id != null) {
						try {
							model.setCurrentID(id);
						} catch (InvalidHelpSetContextException ex) {
							model.setCurrentURL(url);
						}
					} else {
						model.setCurrentURL(url);
					}
				} catch (IOException ioe) {
					loadingURL = false;
					html.setDocument(doc);
					html.getToolkit().beep();
				} finally {
					// schedule the cursor to revert after
					// the paint has happended.
					url = null;
					SwingUtilities.invokeLater(this);
				}
			}
		}

		URL url;

		Cursor cursor;
	}

	/**
	 * Determines if highlights have changed. Collects all the highlights and
	 * marks the presentation.
	 * 
	 * @param e
	 *            The TextHelpModelEvent.
	 */
	public void highlightsChanged(TextHelpModelEvent e) {
		debug("highlightsChanged " + e);

		// if we're loading this url this event will need to wait
		// until we're notified that the page has finished loaded.
		// we could wait(), but that would prevent the execution of
		// other events in this thread. Instead preserve the
		// TextHelpModelEvent and recall this method when the notification
		// occurs.
		if (loadingURL) {
			debug("Humm. loadingURL wait a little");
			pendingHighlightsEvent = e;
			return;
		}

		Highlighter h = html.getHighlighter();
		debug1("removeAllHighlights");
		h.removeAllHighlights();

		TextHelpModel m = (TextHelpModel) e.getSource();
		TextHelpModel.Highlight highlights[] = m.getHighlights();

		Highlighter.HighlightPainter p = new DefaultHighlighter.DefaultHighlightPainter(
				html.getSelectionColor());
		for (int i = 0; i < highlights.length; i++) {
			int pos0 = highlights[i].getStartOffset();
			int pos1 = highlights[i].getEndOffset();
			debug("  highlight: " + pos0 + ", " + pos1);
			try {
				h.addHighlight(pos0, pos1, p);

				// scroll to the first position
				if (i == 0) {
					Runnable callScrollToPosition = new ScrollToPosition(html,
							pos1);
					SwingUtilities.invokeLater(callScrollToPosition);
				}
			} catch (BadLocationException bl) {
				debug("badLocationExcetpion thrown - " + bl);
			}
		}
		RepaintManager.currentManager(html).markCompletelyDirty(html);
	}

	private class ScrollToPosition implements Runnable {
		private int pos;

		private JEditorPane html;

		public ScrollToPosition(JEditorPane html, int pos) {
			this.html = html;
			this.pos = pos;
		}

		public void run() {
			try {
				Rectangle rec = html.modelToView(pos);
				if (rec != null) {
					html.scrollRectToVisible(rec);
				}
			} catch (BadLocationException bl) {
			}
		}
	}

	/**
	 * For printf debugging.
	 */
	private final static boolean debug = false;

	private static void debug(String str) {
		if (debug) {
			System.out.println("SimpleContentViewerUI: " + str);
		}
	}

	private final static boolean debug1 = false;

	private static void debug1(String str) {
		if (debug1) {
			System.out.println("SimpleContentViewerUI: " + str);
		}
	}
}