plugins/org.eclipse.mat.ui/src/org/eclipse/mat/ui/internal/views/NotesView.java - mat/org.eclipse.mat - Git at Google

 /*******************************************************************************
  * Copyright (c) 2008, 2023 SAP AG and IBM Corporation.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *    SAP AG - initial API and implementation
  *    Andrew Johnson - improved undo
  *******************************************************************************/
 package org.eclipse.mat.ui.internal.views;

 import java.io.BufferedOutputStream;
 import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.UncheckedIOException;
 import java.io.UnsupportedEncodingException;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.regex.Pattern;
 import java.util.zip.CRC32;

 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.jface.action.Action;
 import org.eclipse.jface.action.IMenuListener;
 import org.eclipse.jface.action.IMenuManager;
 import org.eclipse.jface.action.MenuManager;
 import org.eclipse.jface.action.Separator;
 import org.eclipse.jface.preference.JFacePreferences;
 import org.eclipse.jface.resource.JFaceResources;
 import org.eclipse.jface.text.BadLocationException;
 import org.eclipse.jface.text.Document;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.IRegion;
 import org.eclipse.jface.text.ITextListener;
 import org.eclipse.jface.text.ITextOperationTarget;
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.Region;
 import org.eclipse.jface.text.TextEvent;
 import org.eclipse.jface.text.TextPresentation;
 import org.eclipse.jface.text.TextViewer;
 import org.eclipse.jface.text.TextViewerUndoManager;
 import org.eclipse.jface.text.hyperlink.AbstractHyperlinkDetector;
 import org.eclipse.jface.text.hyperlink.DefaultHyperlinkPresenter;
 import org.eclipse.jface.text.hyperlink.IHyperlink;
 import org.eclipse.jface.text.hyperlink.IHyperlinkDetector;
 import org.eclipse.jface.viewers.ISelectionChangedListener;
 import org.eclipse.jface.viewers.SelectionChangedEvent;
 import org.eclipse.jface.viewers.StructuredSelection;
 import org.eclipse.mat.SnapshotException;
 import org.eclipse.mat.query.ContextProvider;
 import org.eclipse.mat.query.IContextObject;
 import org.eclipse.mat.ui.editor.MultiPaneEditor;
 import org.eclipse.mat.ui.util.PopupMenu;
 import org.eclipse.mat.ui.util.QueryContextMenu;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.custom.StyleRange;
 import org.eclipse.swt.custom.StyledText;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.graphics.Font;
 import org.eclipse.swt.layout.FillLayout;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Menu;
 import org.eclipse.ui.IActionBars;
 import org.eclipse.ui.IPartListener;
 import org.eclipse.ui.ISaveablePart;
 import org.eclipse.ui.ISaveablePart2;
 import org.eclipse.ui.IWorkbenchPage;
 import org.eclipse.ui.IWorkbenchPart;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.actions.ActionFactory;
 import org.eclipse.ui.actions.ActionFactory.IWorkbenchAction;
 import org.eclipse.ui.part.ViewPart;

 public class NotesView extends ViewPart implements IPartListener, ISaveablePart, ISaveablePart2
 {
     private static final String NOTES_ENCODING = "UTF8"; //$NON-NLS-1$

     private static final int UNDO_LEVEL = 25;

     private File resource;

     private Action undo;
     private Action redo;

     private Menu menu;
     private Font font;
     private Color hyperlinkColor;

     private MultiPaneEditor editor;

     private TextViewer textViewer;
     private TextViewerUndoManager undoManager;
     private Map<String, NotesViewAction> actions = new HashMap<String, NotesViewAction>();
     long hash;
     boolean modified;

     @Override
     public void createPartControl(Composite parent)
     {
         parent.setLayout(new FillLayout());
         // No need for a dispose listener - the SaveablePart will save it

         textViewer = new TextViewer(parent, SWT.MULTI | SWT.V_SCROLL | SWT.LEFT | SWT.H_SCROLL);
         textViewer.setDocument(new Document());
         textViewer.getControl().setEnabled(false);
         textViewer.getTextWidget().setWordWrap(false);
         font = JFaceResources.getFont("org.eclipse.mat.ui.notesfont"); //$NON-NLS-1$
         textViewer.getControl().setFont(font);

         hyperlinkColor = JFaceResources.getColorRegistry().get(JFacePreferences.HYPERLINK_COLOR);

         getSite().getPage().addPartListener(this);

         int undolevel = Platform.getPreferencesService().getInt("org.eclipse.ui.editors", "undoHistorySize", UNDO_LEVEL, null); //$NON-NLS-1$ //$NON-NLS-2$
         undoManager = new TextViewerUndoManager(undolevel);
         undoManager.connect(textViewer);
         textViewer.setUndoManager(undoManager);

         textViewer.addSelectionChangedListener(new ISelectionChangedListener()
         {
             public void selectionChanged(SelectionChangedEvent event)
             {
                 updateActions();
             }
         });

         textViewer.addTextListener(new ITextListener()
         {
             public void textChanged(TextEvent event)
             {
                 modified = true;
                 searchForHyperlinks(textViewer.getDocument().get(), 0);
                 firePropertyChange(PROP_DIRTY);
             }
         });

         textViewer.setHyperlinkPresenter(new DefaultHyperlinkPresenter(hyperlinkColor));
         textViewer.setHyperlinkDetectors(new IHyperlinkDetector[] { new ObjectAddressHyperlinkDetector() }, SWT.MOD1);

         makeActions();
         hookContextMenu();
         showBootstrapPart();
         updateActions();
     }

     private void updateActions()
     {
         for (NotesViewAction a : actions.values())
             a.setEnabled(textViewer.canDoOperation(a.actionId));
     }

     private void hookContextMenu()
     {
         MenuManager menuMgr = new MenuManager("#PopupMenu"); //$NON-NLS-1$
         menuMgr.setRemoveAllWhenShown(true);
         menuMgr.addMenuListener(new IMenuListener()
         {
             public void menuAboutToShow(IMenuManager manager)
             {
                 textEditorContextMenuAboutToShow(manager);
             }
         });
         Menu menu = menuMgr.createContextMenu(textViewer.getControl());
         textViewer.getControl().setMenu(menu);
     }

     private void textEditorContextMenuAboutToShow(IMenuManager manager)
     {
         if (textViewer != null)
         {
             undo.setEnabled(undoManager.undoable());
             redo.setEnabled(undoManager.redoable());
             manager.add(undo);
             manager.add(redo);
             manager.add(new Separator());

             manager.add(getAction(ActionFactory.CUT.getId()));
             manager.add(getAction(ActionFactory.COPY.getId()));
             manager.add(getAction(ActionFactory.PASTE.getId()));
             manager.add(new Separator());
             manager.add(getAction(ActionFactory.DELETE.getId()));
             manager.add(getAction(ActionFactory.SELECT_ALL.getId()));
         }
     }

     private NotesViewAction getAction(String actionID)
     {
         return actions.get(actionID);
     }

     private Action addAction(ActionFactory actionFactory, int textOperation, String actionDefinitionId)
     {
         IWorkbenchWindow window = getViewSite().getWorkbenchWindow();
         IWorkbenchAction globalAction = actionFactory.create(window);

         // Create our text action.
         NotesViewAction action = new NotesViewAction(textOperation, actionDefinitionId);
         actions.put(actionFactory.getId(), action);
         // Copy its properties from the global action.
         action.setText(globalAction.getText());
         action.setToolTipText(globalAction.getToolTipText());
         action.setDescription(globalAction.getDescription());
         action.setImageDescriptor(globalAction.getImageDescriptor());

         action.setDisabledImageDescriptor(globalAction.getDisabledImageDescriptor());
         action.setAccelerator(globalAction.getAccelerator());

         // Register our text action with the global action handler.
         IActionBars actionBars = getViewSite().getActionBars();
         actionBars.setGlobalActionHandler(actionFactory.getId(), action);
         return action;
     }

     @Override
     public void setFocus()
     {
         textViewer.getControl().setFocus();
     }

     public void partActivated(IWorkbenchPart part)
     {
         if (!supportsNotes(part))
             return;

         textViewer.getControl().setEnabled(true);
         editor = (MultiPaneEditor) part;
         File path = editor.getResourceFile();

         if (path != null && !path.equals(resource))
         {
             if (isDirty())
                 saveNotes();
             resource = path;
             updateTextViewer();
         }
     }

     public void partBroughtToTop(IWorkbenchPart part)
     {
         partActivated(part);
     }

     public void partClosed(IWorkbenchPart part)
     {
         if (!supportsNotes(part)) { return; }

         MultiPaneEditor editor = (MultiPaneEditor) part;
         File resource = editor.getResourceFile();

         if (resource.equals(this.resource))
         {
             // Saving usually done as SaveablePart except when snapshot is closed
             if (isDirty())
                 saveNotes();
             this.resource = null;
             this.editor = null;
             this.updateTextViewer();
         }
     }

     public void partDeactivated(IWorkbenchPart part)
     {}

     public void partOpened(IWorkbenchPart part)
     {}

     private void showBootstrapPart()
     {
         IWorkbenchPage page = getSite().getPage();
         if (page != null)
             partActivated(page.getActiveEditor());
     }

     private void makeActions()
     {
         // Install the standard text actions.
         addAction(ActionFactory.CUT, ITextOperationTarget.CUT, "org.eclipse.ui.edit.cut");//$NON-NLS-1$
         addAction(ActionFactory.COPY, ITextOperationTarget.COPY, "org.eclipse.ui.edit.copy");//$NON-NLS-1$
         addAction(ActionFactory.PASTE, ITextOperationTarget.PASTE, "org.eclipse.ui.edit.paste");//$NON-NLS-1$
         addAction(ActionFactory.DELETE, ITextOperationTarget.DELETE, "org.eclipse.ui.edit.delete");//$NON-NLS-1$
         addAction(ActionFactory.SELECT_ALL, ITextOperationTarget.SELECT_ALL, "org.eclipse.ui.edit.selectAll");//$NON-NLS-1$
         undo = addAction(ActionFactory.UNDO, ITextOperationTarget.UNDO, "org.eclipse.ui.edit.undo");//$NON-NLS-1$
         redo = addAction(ActionFactory.REDO, ITextOperationTarget.REDO, "org.eclipse.ui.edit.redo");//$NON-NLS-1$
     }

     private long hash() {
         // Used to detect if document has changed.
         CRC32 crc = new CRC32();
         try
         {
             crc.update(textViewer.getDocument().get().getBytes(NOTES_ENCODING));
         }
         catch (UnsupportedEncodingException e)
         {
             // Won't happen
             return textViewer.getDocument().get().hashCode();
         }
         return crc.getValue();
     }

     private void updateTextViewer()
     {
         // get notes.txt and if it's not null set is as input
         if (resource != null)
         {
             String buffer = readNotes(resource);
             if (buffer != null)
             {
                 Document document = new Document(buffer);
                 textViewer.setDocument(document);
                 revealEndOfDocument();
             }
             else
             {
                 textViewer.setDocument(new Document(""));//$NON-NLS-1$
             }
         }
         else
         {
             textViewer.setDocument(new Document(""));//$NON-NLS-1$
             textViewer.getControl().setEnabled(false);
         }
         hash = hash();
         modified = false;
         firePropertyChange(PROP_DIRTY);
     }

     private void searchForHyperlinks(String allText, int offset)
     {
         if (resource == null)
             return;
         Pattern addressPattern = Pattern.compile("0x\\p{XDigit}+");//$NON-NLS-1$
         String[] fields = allText.split("\\W", 0);//$NON-NLS-1$
         List<IdHyperlink> hyperlinks = new ArrayList<IdHyperlink>();

         for (String field : fields)
         {
             if (addressPattern.matcher(field).matches())
             {
                 IRegion idRegion = new Region(offset, field.length());
                 IdHyperlink hyperlink = new IdHyperlink(field, editor, idRegion);
                 hyperlinks.add(hyperlink);
             }
             offset = offset + field.length() + 1; // length of the splitter
         }
         if (!hyperlinks.isEmpty())
             highlightHyperlinks(hyperlinks);
     }

     private void highlightHyperlinks(List<IdHyperlink> hyperlinks)
     {
         TextPresentation style = new TextPresentation();
         for (IHyperlink hyperlink : hyperlinks)
         {
             int startIndex = hyperlink.getHyperlinkRegion().getOffset();
             int length = hyperlink.getHyperlinkRegion().getLength();
             StyleRange styleRange = new StyleRange(startIndex, length, hyperlinkColor, null, SWT.ITALIC);
             styleRange.underline = true;
             style.addStyleRange(styleRange);
         }
         textViewer.changeTextPresentation(style, true);
     }

     private void saveNotes()
     {
         if (resource != null)
         {
             String text = textViewer.getDocument().get();
             if (text != null)
                 saveNotes(resource, text);
             resetUndoManager();
             hash = hash();
             modified = false;
         }
     }

     @Override
     public void dispose()
     {
         undoManager.disconnect();
         getSite().getPage().removePartListener(this);
         // The parent composite has been disposed, so there is no need to remove the disposeListener.
         if (menu != null)
             menu.dispose();
         super.dispose();
     }

     private boolean supportsNotes(IWorkbenchPart part)
     {
         if (part instanceof MultiPaneEditor)
         {
             return true;
         }
         return false;
     }

     protected void revealEndOfDocument()
     {
         IDocument doc = textViewer.getDocument();
         int docLength = doc.getLength();
         if (docLength > 0)
         {
             textViewer.revealRange(docLength - 1, 1);
             StyledText widget = textViewer.getTextWidget();
             widget.setCaretOffset(docLength);
         }
     }

     public void resetUndoManager()
     {
         undoManager.reset();
     }

     private final class IdHyperlink implements IHyperlink
     {

         String id;
         MultiPaneEditor editor;
         IRegion region;

         public IdHyperlink(String id, MultiPaneEditor editor, IRegion region)
         {
             this.id = id;
             this.editor = editor;
             this.region = region;
         }

         public IRegion getHyperlinkRegion()
         {
             return region;
         }

         public String getHyperlinkText()
         {
             return null;
         }

         public String getTypeLabel()
         {
             return null;
         }

         public void open()
         {
             try
             {
                 final int objectId = editor.getQueryContext().mapToObjectId(id);
                 if (objectId < 0)
                     return;

                 QueryContextMenu contextMenu = new QueryContextMenu(editor, new ContextProvider((String) null)
                 {
                     @Override
                     public IContextObject getContext(final Object row)
                     {
                         return new IContextObject()
                         {

                             public int getObjectId()
                             {
                                 return (Integer) row;
                             }

                         };
                     }
                 });

                 PopupMenu popupMenu = new PopupMenu();
                 contextMenu.addContextActions(popupMenu, new StructuredSelection(objectId), null);

                 if (menu != null && !menu.isDisposed())
                     menu.dispose();

                 menu = popupMenu.createMenu(getViewSite().getActionBars().getStatusLineManager(), PlatformUI
                                 .getWorkbench().getDisplay().getActiveShell());
                 menu.setVisible(true);
             }
             catch (NumberFormatException ignore)
             {
                 // $JL-EXC$
                 // shouldn't happen and if it does nothing can be done
             }
             catch (SnapshotException ignore)
             {
                 // $JL-EXC$
                 // mapToAddress throws exception on illegal values
             }

         }
     }

     private class ObjectAddressHyperlinkDetector extends AbstractHyperlinkDetector
     {

         public IHyperlink[] detectHyperlinks(ITextViewer textViewer, IRegion region, boolean canShowMultipleHyperlinks)
         {
             if (region == null || textViewer == null)
                 return null;

             IDocument document = textViewer.getDocument();

             int offset = region.getOffset();
             if (document == null)
                 return null;

             IRegion lineInfo;
             String text;
             try
             {
                 lineInfo = document.getLineInformationOfOffset(offset);
                 text = document.get(lineInfo.getOffset(), lineInfo.getLength());
             }
             catch (BadLocationException ex)
             {
                 return null;
             }
             int index = offset - lineInfo.getOffset();
             // to the left from offset
             char ch;
             do
             {
                 index--;
                 ch = ' ';
                 if (index > -1)
                     ch = text.charAt(index);
             }
             while (Character.isLetterOrDigit(ch));
             int startIndex = index + 1;

             // to the right from offset
             index = offset - lineInfo.getOffset() - 1;
             do
             {
                 index++;
                 if (index >= text.length())
                 {
                     break;
                 }
                 ch = text.charAt(index);
             }
             while (Character.isLetterOrDigit(ch));

             Pattern addressPattern = Pattern.compile("0x\\p{XDigit}+");//$NON-NLS-1$
             String address = text.substring(startIndex, index);
             if (address != null && addressPattern.matcher(address).matches())
             {
                 IRegion idRegion = new Region(startIndex, address.length());
                 return new IHyperlink[] { new IdHyperlink(address, editor, idRegion) };
             }
             else
                 return null;
         }
     }

     private class NotesViewAction extends Action
     {
         private int actionId;

         NotesViewAction(int actionId, String actionDefinitionId)
         {
             this.actionId = actionId;
             this.setActionDefinitionId(actionDefinitionId);
         }

         @Override
         public boolean isEnabled()
         {
             return textViewer.canDoOperation(actionId);
         }

         public void run()
         {
             textViewer.doOperation(actionId);
         }

     }

     // //////////////////////////////////////////////////////////////
     // notes management
     // //////////////////////////////////////////////////////////////

     /**
      * Read the contents of the notes file, based on the
      * snapshot resource.
      * @param resourcePath The editor file (snapshot or index file).
      * @return The contents of the notes file, lines separated by \n.
      * @throws {@link UncheckedIOException} for some IO errors.
      */
     public static String readNotes(File resourcePath)
     {
         if (resourcePath != null)
         {
             File notesFile = getDefaultNotesFile(resourcePath);
             if (notesFile.canRead() && notesFile.isFile())
             {
                 try (FileInputStream fileInput = new FileInputStream(notesFile))
                 {
                     BufferedReader myInput = new BufferedReader(new InputStreamReader(fileInput, NOTES_ENCODING));

                     try
                     {
                         String s;
                         StringBuffer b = new StringBuffer();
                         while ((s = myInput.readLine()) != null)
                         {
                             b.append(s);
                             b.append("\n");//$NON-NLS-1$
                         }
                         return b.toString();
                     }
                     finally
                     {
                         try
                         {
                             myInput.close();
                         }
                         catch (IOException ignore)
                         {}
                     }
                 }
                 catch (FileNotFoundException e)
                 {
                     throw new UncheckedIOException(notesFile.getPath(), e);
                 }
                 catch (IOException e)
                 {
                     throw new UncheckedIOException(notesFile.getPath(), e);
                 }
             }
         }
         return null;
     }

     private static void saveNotes(File resource, String notes)
     {
         OutputStream fout = null;

         try
         {
             File notesFile = getDefaultNotesFile(resource);

             fout = new FileOutputStream(notesFile);
             OutputStreamWriter out = new OutputStreamWriter(new BufferedOutputStream(fout), NOTES_ENCODING);
             try
             {
                 out.write(notes);
                 out.flush();
             }
             finally
             {
                 out.close();
             }
         }
         catch (FileNotFoundException e)
         {
             throw new RuntimeException(e);
         }
         catch (IOException e)
         {
             throw new RuntimeException(e);
         }
         finally
         {
             try
             {
                 if (fout != null)
                     fout.close();
             }
             catch (IOException ignore)
             {}
         }
     }

     private static File getDefaultNotesFile(File resource)
     {
         String filename = resource.getName();
         int p = filename.lastIndexOf('.');
         if (p >= 0)
             filename = filename.substring(0, p);
         return new File(resource.getParentFile(), filename + ".notes.txt");//$NON-NLS-1$
     }

     public void doSave(IProgressMonitor monitor)
     {
         saveNotes();
         firePropertyChange(PROP_DIRTY);
     }

     public void doSaveAs()
     {
     }

     public boolean isDirty()
     {
         return undoManager.undoable() || modified && hash != hash();
     }

     public boolean isSaveAsAllowed()
     {
         return false;
     }

     public boolean isSaveOnCloseNeeded()
     {
         return true;
     }

     public int promptToSaveOnClose()
     {
         return ISaveablePart2.YES;
     }

 }
	/*******************************************************************************
	* Copyright (c) 2008, 2023 SAP AG and IBM Corporation.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* SAP AG - initial API and implementation
	* Andrew Johnson - improved undo
	*******************************************************************************/
	package org.eclipse.mat.ui.internal.views;

	import java.io.BufferedOutputStream;
	import java.io.BufferedReader;
	import java.io.File;
	import java.io.FileInputStream;
	import java.io.FileNotFoundException;
	import java.io.FileOutputStream;
	import java.io.IOException;
	import java.io.InputStreamReader;
	import java.io.OutputStream;
	import java.io.OutputStreamWriter;
	import java.io.UncheckedIOException;
	import java.io.UnsupportedEncodingException;
	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map;
	import java.util.regex.Pattern;
	import java.util.zip.CRC32;

	import org.eclipse.core.runtime.IProgressMonitor;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.jface.action.Action;
	import org.eclipse.jface.action.IMenuListener;
	import org.eclipse.jface.action.IMenuManager;
	import org.eclipse.jface.action.MenuManager;
	import org.eclipse.jface.action.Separator;
	import org.eclipse.jface.preference.JFacePreferences;
	import org.eclipse.jface.resource.JFaceResources;
	import org.eclipse.jface.text.BadLocationException;
	import org.eclipse.jface.text.Document;
	import org.eclipse.jface.text.IDocument;
	import org.eclipse.jface.text.IRegion;
	import org.eclipse.jface.text.ITextListener;
	import org.eclipse.jface.text.ITextOperationTarget;
	import org.eclipse.jface.text.ITextViewer;
	import org.eclipse.jface.text.Region;
	import org.eclipse.jface.text.TextEvent;
	import org.eclipse.jface.text.TextPresentation;
	import org.eclipse.jface.text.TextViewer;
	import org.eclipse.jface.text.TextViewerUndoManager;
	import org.eclipse.jface.text.hyperlink.AbstractHyperlinkDetector;
	import org.eclipse.jface.text.hyperlink.DefaultHyperlinkPresenter;
	import org.eclipse.jface.text.hyperlink.IHyperlink;
	import org.eclipse.jface.text.hyperlink.IHyperlinkDetector;
	import org.eclipse.jface.viewers.ISelectionChangedListener;
	import org.eclipse.jface.viewers.SelectionChangedEvent;
	import org.eclipse.jface.viewers.StructuredSelection;
	import org.eclipse.mat.SnapshotException;
	import org.eclipse.mat.query.ContextProvider;
	import org.eclipse.mat.query.IContextObject;
	import org.eclipse.mat.ui.editor.MultiPaneEditor;
	import org.eclipse.mat.ui.util.PopupMenu;
	import org.eclipse.mat.ui.util.QueryContextMenu;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.custom.StyleRange;
	import org.eclipse.swt.custom.StyledText;
	import org.eclipse.swt.graphics.Color;
	import org.eclipse.swt.graphics.Font;
	import org.eclipse.swt.layout.FillLayout;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Menu;
	import org.eclipse.ui.IActionBars;
	import org.eclipse.ui.IPartListener;
	import org.eclipse.ui.ISaveablePart;
	import org.eclipse.ui.ISaveablePart2;
	import org.eclipse.ui.IWorkbenchPage;
	import org.eclipse.ui.IWorkbenchPart;
	import org.eclipse.ui.IWorkbenchWindow;
	import org.eclipse.ui.PlatformUI;
	import org.eclipse.ui.actions.ActionFactory;
	import org.eclipse.ui.actions.ActionFactory.IWorkbenchAction;
	import org.eclipse.ui.part.ViewPart;

	public class NotesView extends ViewPart implements IPartListener, ISaveablePart, ISaveablePart2
	{
	private static final String NOTES_ENCODING = "UTF8"; //$NON-NLS-1$

	private static final int UNDO_LEVEL = 25;

	private File resource;

	private Action undo;
	private Action redo;

	private Menu menu;
	private Font font;
	private Color hyperlinkColor;

	private MultiPaneEditor editor;

	private TextViewer textViewer;
	private TextViewerUndoManager undoManager;
	private Map<String, NotesViewAction> actions = new HashMap<String, NotesViewAction>();
	long hash;
	boolean modified;

	@Override
	public void createPartControl(Composite parent)
	{
	parent.setLayout(new FillLayout());
	// No need for a dispose listener - the SaveablePart will save it

	textViewer = new TextViewer(parent, SWT.MULTI \| SWT.V_SCROLL \| SWT.LEFT \| SWT.H_SCROLL);
	textViewer.setDocument(new Document());
	textViewer.getControl().setEnabled(false);
	textViewer.getTextWidget().setWordWrap(false);
	font = JFaceResources.getFont("org.eclipse.mat.ui.notesfont"); //$NON-NLS-1$
	textViewer.getControl().setFont(font);

	hyperlinkColor = JFaceResources.getColorRegistry().get(JFacePreferences.HYPERLINK_COLOR);

	getSite().getPage().addPartListener(this);

	int undolevel = Platform.getPreferencesService().getInt("org.eclipse.ui.editors", "undoHistorySize", UNDO_LEVEL, null); //$NON-NLS-1$ //$NON-NLS-2$
	undoManager = new TextViewerUndoManager(undolevel);
	undoManager.connect(textViewer);
	textViewer.setUndoManager(undoManager);

	textViewer.addSelectionChangedListener(new ISelectionChangedListener()
	{
	public void selectionChanged(SelectionChangedEvent event)
	{
	updateActions();
	}
	});

	textViewer.addTextListener(new ITextListener()
	{
	public void textChanged(TextEvent event)
	{
	modified = true;
	searchForHyperlinks(textViewer.getDocument().get(), 0);
	firePropertyChange(PROP_DIRTY);
	}
	});

	textViewer.setHyperlinkPresenter(new DefaultHyperlinkPresenter(hyperlinkColor));
	textViewer.setHyperlinkDetectors(new IHyperlinkDetector[] { new ObjectAddressHyperlinkDetector() }, SWT.MOD1);

	makeActions();
	hookContextMenu();
	showBootstrapPart();
	updateActions();
	}

	private void updateActions()
	{
	for (NotesViewAction a : actions.values())
	a.setEnabled(textViewer.canDoOperation(a.actionId));
	}

	private void hookContextMenu()
	{
	MenuManager menuMgr = new MenuManager("#PopupMenu"); //$NON-NLS-1$
	menuMgr.setRemoveAllWhenShown(true);
	menuMgr.addMenuListener(new IMenuListener()
	{
	public void menuAboutToShow(IMenuManager manager)
	{
	textEditorContextMenuAboutToShow(manager);
	}
	});
	Menu menu = menuMgr.createContextMenu(textViewer.getControl());
	textViewer.getControl().setMenu(menu);
	}

	private void textEditorContextMenuAboutToShow(IMenuManager manager)
	{
	if (textViewer != null)
	{
	undo.setEnabled(undoManager.undoable());
	redo.setEnabled(undoManager.redoable());
	manager.add(undo);
	manager.add(redo);
	manager.add(new Separator());

	manager.add(getAction(ActionFactory.CUT.getId()));
	manager.add(getAction(ActionFactory.COPY.getId()));
	manager.add(getAction(ActionFactory.PASTE.getId()));
	manager.add(new Separator());
	manager.add(getAction(ActionFactory.DELETE.getId()));
	manager.add(getAction(ActionFactory.SELECT_ALL.getId()));
	}
	}

	private NotesViewAction getAction(String actionID)
	{
	return actions.get(actionID);
	}

	private Action addAction(ActionFactory actionFactory, int textOperation, String actionDefinitionId)
	{
	IWorkbenchWindow window = getViewSite().getWorkbenchWindow();
	IWorkbenchAction globalAction = actionFactory.create(window);

	// Create our text action.
	NotesViewAction action = new NotesViewAction(textOperation, actionDefinitionId);
	actions.put(actionFactory.getId(), action);
	// Copy its properties from the global action.
	action.setText(globalAction.getText());
	action.setToolTipText(globalAction.getToolTipText());
	action.setDescription(globalAction.getDescription());
	action.setImageDescriptor(globalAction.getImageDescriptor());

	action.setDisabledImageDescriptor(globalAction.getDisabledImageDescriptor());
	action.setAccelerator(globalAction.getAccelerator());

	// Register our text action with the global action handler.
	IActionBars actionBars = getViewSite().getActionBars();
	actionBars.setGlobalActionHandler(actionFactory.getId(), action);
	return action;
	}

	@Override
	public void setFocus()
	{
	textViewer.getControl().setFocus();
	}

	public void partActivated(IWorkbenchPart part)
	{
	if (!supportsNotes(part))
	return;

	textViewer.getControl().setEnabled(true);
	editor = (MultiPaneEditor) part;
	File path = editor.getResourceFile();

	if (path != null && !path.equals(resource))
	{
	if (isDirty())
	saveNotes();
	resource = path;
	updateTextViewer();
	}
	}

	public void partBroughtToTop(IWorkbenchPart part)
	{
	partActivated(part);
	}

	public void partClosed(IWorkbenchPart part)
	{
	if (!supportsNotes(part)) { return; }

	MultiPaneEditor editor = (MultiPaneEditor) part;
	File resource = editor.getResourceFile();

	if (resource.equals(this.resource))
	{
	// Saving usually done as SaveablePart except when snapshot is closed
	if (isDirty())
	saveNotes();
	this.resource = null;
	this.editor = null;
	this.updateTextViewer();
	}
	}

	public void partDeactivated(IWorkbenchPart part)
	{}

	public void partOpened(IWorkbenchPart part)
	{}

	private void showBootstrapPart()
	{
	IWorkbenchPage page = getSite().getPage();
	if (page != null)
	partActivated(page.getActiveEditor());
	}

	private void makeActions()
	{
	// Install the standard text actions.
	addAction(ActionFactory.CUT, ITextOperationTarget.CUT, "org.eclipse.ui.edit.cut");//$NON-NLS-1$
	addAction(ActionFactory.COPY, ITextOperationTarget.COPY, "org.eclipse.ui.edit.copy");//$NON-NLS-1$
	addAction(ActionFactory.PASTE, ITextOperationTarget.PASTE, "org.eclipse.ui.edit.paste");//$NON-NLS-1$
	addAction(ActionFactory.DELETE, ITextOperationTarget.DELETE, "org.eclipse.ui.edit.delete");//$NON-NLS-1$
	addAction(ActionFactory.SELECT_ALL, ITextOperationTarget.SELECT_ALL, "org.eclipse.ui.edit.selectAll");//$NON-NLS-1$
	undo = addAction(ActionFactory.UNDO, ITextOperationTarget.UNDO, "org.eclipse.ui.edit.undo");//$NON-NLS-1$
	redo = addAction(ActionFactory.REDO, ITextOperationTarget.REDO, "org.eclipse.ui.edit.redo");//$NON-NLS-1$
	}

	private long hash() {
	// Used to detect if document has changed.
	CRC32 crc = new CRC32();
	try
	{
	crc.update(textViewer.getDocument().get().getBytes(NOTES_ENCODING));
	}
	catch (UnsupportedEncodingException e)
	{
	// Won't happen
	return textViewer.getDocument().get().hashCode();
	}
	return crc.getValue();
	}

	private void updateTextViewer()
	{
	// get notes.txt and if it's not null set is as input
	if (resource != null)
	{
	String buffer = readNotes(resource);
	if (buffer != null)
	{
	Document document = new Document(buffer);
	textViewer.setDocument(document);
	revealEndOfDocument();
	}
	else
	{
	textViewer.setDocument(new Document(""));//$NON-NLS-1$
	}
	}
	else
	{
	textViewer.setDocument(new Document(""));//$NON-NLS-1$
	textViewer.getControl().setEnabled(false);
	}
	hash = hash();
	modified = false;
	firePropertyChange(PROP_DIRTY);
	}

	private void searchForHyperlinks(String allText, int offset)
	{
	if (resource == null)
	return;
	Pattern addressPattern = Pattern.compile("0x\\p{XDigit}+");//$NON-NLS-1$
	String[] fields = allText.split("\\W", 0);//$NON-NLS-1$
	List<IdHyperlink> hyperlinks = new ArrayList<IdHyperlink>();

	for (String field : fields)
	{
	if (addressPattern.matcher(field).matches())
	{
	IRegion idRegion = new Region(offset, field.length());
	IdHyperlink hyperlink = new IdHyperlink(field, editor, idRegion);
	hyperlinks.add(hyperlink);
	}
	offset = offset + field.length() + 1; // length of the splitter
	}
	if (!hyperlinks.isEmpty())
	highlightHyperlinks(hyperlinks);
	}

	private void highlightHyperlinks(List<IdHyperlink> hyperlinks)
	{
	TextPresentation style = new TextPresentation();
	for (IHyperlink hyperlink : hyperlinks)
	{
	int startIndex = hyperlink.getHyperlinkRegion().getOffset();
	int length = hyperlink.getHyperlinkRegion().getLength();
	StyleRange styleRange = new StyleRange(startIndex, length, hyperlinkColor, null, SWT.ITALIC);
	styleRange.underline = true;
	style.addStyleRange(styleRange);
	}
	textViewer.changeTextPresentation(style, true);
	}

	private void saveNotes()
	{
	if (resource != null)
	{
	String text = textViewer.getDocument().get();
	if (text != null)
	saveNotes(resource, text);
	resetUndoManager();
	hash = hash();
	modified = false;
	}
	}

	@Override
	public void dispose()
	{
	undoManager.disconnect();
	getSite().getPage().removePartListener(this);
	// The parent composite has been disposed, so there is no need to remove the disposeListener.
	if (menu != null)
	menu.dispose();
	super.dispose();
	}

	private boolean supportsNotes(IWorkbenchPart part)
	{
	if (part instanceof MultiPaneEditor)
	{
	return true;
	}
	return false;
	}

	protected void revealEndOfDocument()
	{
	IDocument doc = textViewer.getDocument();
	int docLength = doc.getLength();
	if (docLength > 0)
	{
	textViewer.revealRange(docLength - 1, 1);
	StyledText widget = textViewer.getTextWidget();
	widget.setCaretOffset(docLength);
	}
	}

	public void resetUndoManager()
	{
	undoManager.reset();
	}

	private final class IdHyperlink implements IHyperlink
	{

	String id;
	MultiPaneEditor editor;
	IRegion region;

	public IdHyperlink(String id, MultiPaneEditor editor, IRegion region)
	{
	this.id = id;
	this.editor = editor;
	this.region = region;
	}

	public IRegion getHyperlinkRegion()
	{
	return region;
	}

	public String getHyperlinkText()
	{
	return null;
	}

	public String getTypeLabel()
	{
	return null;
	}

	public void open()
	{
	try
	{
	final int objectId = editor.getQueryContext().mapToObjectId(id);
	if (objectId < 0)
	return;

	QueryContextMenu contextMenu = new QueryContextMenu(editor, new ContextProvider((String) null)
	{
	@Override
	public IContextObject getContext(final Object row)
	{
	return new IContextObject()
	{

	public int getObjectId()
	{
	return (Integer) row;
	}

	};
	}
	});

	PopupMenu popupMenu = new PopupMenu();
	contextMenu.addContextActions(popupMenu, new StructuredSelection(objectId), null);

	if (menu != null && !menu.isDisposed())
	menu.dispose();

	menu = popupMenu.createMenu(getViewSite().getActionBars().getStatusLineManager(), PlatformUI
	.getWorkbench().getDisplay().getActiveShell());
	menu.setVisible(true);
	}
	catch (NumberFormatException ignore)
	{
	// $JL-EXC$
	// shouldn't happen and if it does nothing can be done
	}
	catch (SnapshotException ignore)
	{
	// $JL-EXC$
	// mapToAddress throws exception on illegal values
	}

	}
	}

	private class ObjectAddressHyperlinkDetector extends AbstractHyperlinkDetector
	{

	public IHyperlink[] detectHyperlinks(ITextViewer textViewer, IRegion region, boolean canShowMultipleHyperlinks)
	{
	if (region == null \|\| textViewer == null)
	return null;

	IDocument document = textViewer.getDocument();

	int offset = region.getOffset();
	if (document == null)
	return null;

	IRegion lineInfo;
	String text;
	try
	{
	lineInfo = document.getLineInformationOfOffset(offset);
	text = document.get(lineInfo.getOffset(), lineInfo.getLength());
	}
	catch (BadLocationException ex)
	{
	return null;
	}
	int index = offset - lineInfo.getOffset();
	// to the left from offset
	char ch;
	do
	{
	index--;
	ch = ' ';
	if (index > -1)
	ch = text.charAt(index);
	}
	while (Character.isLetterOrDigit(ch));
	int startIndex = index + 1;

	// to the right from offset
	index = offset - lineInfo.getOffset() - 1;
	do
	{
	index++;
	if (index >= text.length())
	{
	break;
	}
	ch = text.charAt(index);
	}
	while (Character.isLetterOrDigit(ch));

	Pattern addressPattern = Pattern.compile("0x\\p{XDigit}+");//$NON-NLS-1$
	String address = text.substring(startIndex, index);
	if (address != null && addressPattern.matcher(address).matches())
	{
	IRegion idRegion = new Region(startIndex, address.length());
	return new IHyperlink[] { new IdHyperlink(address, editor, idRegion) };
	}
	else
	return null;
	}
	}

	private class NotesViewAction extends Action
	{
	private int actionId;

	NotesViewAction(int actionId, String actionDefinitionId)
	{
	this.actionId = actionId;
	this.setActionDefinitionId(actionDefinitionId);
	}

	@Override
	public boolean isEnabled()
	{
	return textViewer.canDoOperation(actionId);
	}

	public void run()
	{
	textViewer.doOperation(actionId);
	}

	}

	// //////////////////////////////////////////////////////////////
	// notes management
	// //////////////////////////////////////////////////////////////

	/**
	* Read the contents of the notes file, based on the
	* snapshot resource.
	* @param resourcePath The editor file (snapshot or index file).
	* @return The contents of the notes file, lines separated by \n.
	* @throws {@link UncheckedIOException} for some IO errors.
	*/
	public static String readNotes(File resourcePath)
	{
	if (resourcePath != null)
	{
	File notesFile = getDefaultNotesFile(resourcePath);
	if (notesFile.canRead() && notesFile.isFile())
	{
	try (FileInputStream fileInput = new FileInputStream(notesFile))
	{
	BufferedReader myInput = new BufferedReader(new InputStreamReader(fileInput, NOTES_ENCODING));

	try
	{
	String s;
	StringBuffer b = new StringBuffer();
	while ((s = myInput.readLine()) != null)
	{
	b.append(s);
	b.append("\n");//$NON-NLS-1$
	}
	return b.toString();
	}
	finally
	{
	try
	{
	myInput.close();
	}
	catch (IOException ignore)
	{}
	}
	}
	catch (FileNotFoundException e)
	{
	throw new UncheckedIOException(notesFile.getPath(), e);
	}
	catch (IOException e)
	{
	throw new UncheckedIOException(notesFile.getPath(), e);
	}
	}
	}
	return null;
	}

	private static void saveNotes(File resource, String notes)
	{
	OutputStream fout = null;

	try
	{
	File notesFile = getDefaultNotesFile(resource);

	fout = new FileOutputStream(notesFile);
	OutputStreamWriter out = new OutputStreamWriter(new BufferedOutputStream(fout), NOTES_ENCODING);
	try
	{
	out.write(notes);
	out.flush();
	}
	finally
	{
	out.close();
	}
	}
	catch (FileNotFoundException e)
	{
	throw new RuntimeException(e);
	}
	catch (IOException e)
	{
	throw new RuntimeException(e);
	}
	finally
	{
	try
	{
	if (fout != null)
	fout.close();
	}
	catch (IOException ignore)
	{}
	}
	}

	private static File getDefaultNotesFile(File resource)
	{
	String filename = resource.getName();
	int p = filename.lastIndexOf('.');
	if (p >= 0)
	filename = filename.substring(0, p);
	return new File(resource.getParentFile(), filename + ".notes.txt");//$NON-NLS-1$
	}

	public void doSave(IProgressMonitor monitor)
	{
	saveNotes();
	firePropertyChange(PROP_DIRTY);
	}

	public void doSaveAs()
	{
	}

	public boolean isDirty()
	{
	return undoManager.undoable() \|\| modified && hash != hash();
	}

	public boolean isSaveAsAllowed()
	{
	return false;
	}

	public boolean isSaveOnCloseNeeded()
	{
	return true;
	}

	public int promptToSaveOnClose()
	{
	return ISaveablePart2.YES;
	}

	}