Serializable Problem in GEF

public abstract class Element implements IPropertySource, Cloneable, Serializable {

PropertyChangeSupport listeners = new PropertyChangeSupport(this);

private static final long serialVersionUID = 1;

/** An empty property descriptor. */
private static final IPropertyDescriptor[] EMPTY_ARRAY = new IPropertyDescriptor[0];

public void addPropertyChangeListener(PropertyChangeListener l) {
listeners.addPropertyChangeListener(l);
}

protected void firePropertyChange(String prop, Object old, Object newValue) {
listeners.firePropertyChange(prop, old, newValue);
}

protected void fireStructureChange(String prop, Object child) {
listeners.firePropertyChange(prop, null, child);
}
////
/**
* Returns a value for this property source that can be edited in a property sheet.
*

My personal rule of thumb:

*

*
• model elements should return themselves and

*
• custom IPropertySource implementations (like DimensionPropertySource in the GEF-logic
  * example) should return an editable value.

*

*

Override only if necessary.

* @return this instance
*/
public Object getEditableValue() {
return this;
}

private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject();
listeners = new PropertyChangeSupport(this);
}

public void removePropertyChangeListener(PropertyChangeListener l) {
listeners.removePropertyChangeListener(l);
}

/**
* Children should override this. The default implementation returns an empty array.
*/
public IPropertyDescriptor[] getPropertyDescriptors() {
return EMPTY_ARRAY;
}

/**
* Children should override this. The default implementation does nothing.
*/
public void resetPropertyValue(Object id) {
// do nothing
}

/**
* Children should override this. The default implementation does nothing.
*/
public void setPropertyValue(Object id, Object value) {
// do nothing
}

/**
* Children should override this. The default implementation returns null.
*/
public Object getPropertyValue(Object id) {
return null;
}

/**
* Children should override this. The default implementation returns false.
*/
public boolean isPropertySet(Object id) {
return false;
}

/*
* Created on 2005-1-24
*
* TODO To change the template for this generated file go to
* Window - Preferences - Java - Code Style - Code Templates
*/
package com.example.ui;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IWorkspace;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.gef.DefaultEditDomain;
import org.eclipse.gef.dnd.TemplateTransferDragSourceListener;
import org.eclipse.gef.editparts.ScalableFreeformRootEditPart;
//import org.eclipse.gef.examples.shapes.model.ShapesDiagram;
//import org.eclipse.gef.examples.flow.model.ActivityDiagram;
import org.eclipse.gef.palette.PaletteRoot;
import org.eclipse.gef.ui.actions.ActionRegistry;
import org.eclipse.gef.ui.parts.ContentOutlinePage;
import org.eclipse.gef.ui.parts.GraphicalEditorWithPalette;
import org.eclipse.gef.ui.parts.TreeViewer;
import org.eclipse.jface.dialogs.ProgressMonitorDialog;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.ui.IActionBars;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.IFileEditorInput;
import org.eclipse.ui.IWorkbenchActionConstants;
import org.eclipse.ui.actions.WorkspaceModifyOperation;
import org.eclipse.ui.dialogs.SaveAsDialog;
import org.eclipse.ui.part.FileEditorInput;
import org.eclipse.ui.part.IPageSite;
import org.eclipse.ui.views.contentoutline.IContentOutlinePage;

import com.example.dnd.DiagramTemplateTransferDropTargetListener;
import com.example.model.Diagram;
import com.example.parts.PartFactory;
import com.example.parts.TreePartFactory;
import com.example.tools.PaletteFactory;


public class PracticeEditor extends GraphicalEditorWithPalette {

private Diagram diagram = new Diagram();

private PaletteRoot paletteRoot;

public Diagram getDiagram() {
return this.diagram;
}

public PracticeEditor() {
setEditDomain(new DefaultEditDomain(this));
}

protected void createOutputStream(OutputStream os) throws IOException {
ObjectOutputStream out = new ObjectOutputStream(os);
out.writeObject(diagram);
out.close();
}

protected void configureGraphicalViewer() {
super.configureGraphicalViewer();
getGraphicalViewer().setRootEditPart(new ScalableFreeformRootEditPart());
getGraphicalViewer().setEditPartFactory(new PartFactory());
}

protected void initializeGraphicalViewer() {
getGraphicalViewer().setContents(this.diagram);
getGraphicalViewer().addDropTargetListener(new DiagramTemplateTransferDropTargetListener(getGraphicalViewer()));
}

public void doSave(IProgressMonitor monitor) {
// try {
// InputStream in = diagram.getAsStream();
// IFile file = ((IFileEditorInput)getEditorInput()).getFile();
// file.setContents(in, true, false, monitor);
// getCommandStack().markSaveLocation();
// }
// catch (Exception e) {
// e.printStackTrace();
// }
try{
ByteArrayOutputStream out = new ByteArrayOutputStream();
createOutputStream(out);
IFile file = ((IFileEditorInput)getEditorInput()).getFile();
file.setContents(new ByteArrayInputStream(out.toByteArray()),
true, false, monitor);
out.close();
getCommandStack().markSaveLocation();
}
catch (Exception e) {
e.printStackTrace();
}
}

public void doSaveAs() {
SaveAsDialog dialog= new SaveAsDialog(getSite().getWorkbenchWindow().getShell());
dialog.setOriginalFile(((IFileEditorInput)getEditorInput()).getFile());
dialog.open();
IPath path= dialog.getResult();

if (path == null)
return;

IWorkspace workspace= ResourcesPlugin.getWorkspace();
final IFile file= workspace.getRoot().getFile(path);

WorkspaceModifyOperation op= new WorkspaceModifyOperation() {
public void execute(final IProgressMonitor monitor) throws CoreException {
try {
ByteArrayOutputStream out = new ByteArrayOutputStream();
createOutputStream(out);
file.create(new ByteArrayInputStream(out.toByteArray()), true, monitor);
out.close();
}
catch (Exception e) {
e.printStackTrace();
}
}
};

try {
new ProgressMonitorDialog(getSite().getWorkbenchWindow().getShell()).run(false, true, op);
setInput(new FileEditorInput((IFile)file));
getCommandStack().markSaveLocation();
}
catch (Exception e) {
e.printStackTrace();
}
}

public boolean isDirty() {
return getCommandStack().isDirty();
}

public boolean isSaveAsAllowed() {
return true;
}

protected void setInput(IEditorInput input) {
// super.setInput(input);
// try {
// IFile file = ((IFileEditorInput) input).getFile();
// ObjectInputStream in = new ObjectInputStream(file.getContents());
// diagram = (Diagram) in.readObject();
// in.close();
// setPartName(file.getName());
// }
// catch (Exception e) {
// //This is just an example. All exceptions caught here.
// e.printStackTrace();
// diagram = new Diagram();
// }

// super.setInput(input);
//
// IFile file = ((IFileEditorInput)input).getFile();
// try {
// InputStream is = file.getContents(false);
// ObjectInputStream ois = new ObjectInputStream(is);
// diagram = (Diagram)ois.readObject();
// ois.close();
// } catch (Exception e) {
// //This is just an example. All exceptions caught here.
// e.printStackTrace();
// diagram = new Diagram();
// }

super.setInput(input);

IFile file = ((IFileEditorInput) input).getFile();
// diagram = new Diagram();
try { // attempt to read from a file
InputStream istream = file.getContents(false);
diagram = Diagram.makeFromStream(istream);
} catch (Exception e) { // but if there's an error, create a new diagram
e.printStackTrace();
diagram = new Diagram();
}
}

public Object getAdapter(Class type) {
if (type == IContentOutlinePage.class)
return new OutlinePage();
return super.getAdapter(type);
}

protected PaletteRoot getPaletteRoot() {
if (this.paletteRoot == null) {
this.paletteRoot = PaletteFactory.createPalette();
}
return this.paletteRoot;
}

protected void initializePaletteViewer() {
super.initializePaletteViewer();
getPaletteViewer().addDragSourceListener(new TemplateTransferDragSourceListener(getPaletteViewer()));
}

class OutlinePage extends ContentOutlinePage {
// private PageBook pageBook;

private Control outline;

public OutlinePage() {
super(new TreeViewer());
}

public void init(IPageSite pageSite) {
super.init(pageSite);
ActionRegistry registry = getActionRegistry();
IActionBars bars = pageSite.getActionBars();
String id = IWorkbenchActionConstants.UNDO;
bars.setGlobalActionHandler(id, registry.getAction(id));
id = IWorkbenchActionConstants.REDO;
bars.setGlobalActionHandler(id, registry.getAction(id));
id = IWorkbenchActionConstants.DELETE;
bars.setGlobalActionHandler(id, registry.getAction(id));
bars.updateActionBars();
}

public void createControl(Composite parent) {
// pageBook = new PageBook(parent, SWT.NONE);
// outline = getViewer().createControl(pageBook);
// pageBook.showPage(outline);
outline = getViewer().createControl(parent);
getSelectionSynchronizer().addViewer(getViewer());
getViewer().setEditDomain(getEditDomain());
getViewer().setEditPartFactory(new TreePartFactory());
// getViewer().setKeyHandler(getCommonKeyHandler());
getViewer().setContents(getDiagram());
}

public Control getControl() {
// return pageBook;
return outline;
}

public void dispose() {
getSelectionSynchronizer().removeViewer(getViewer());
super.dispose();
}
}

}


java.io.NotSerializableException: org.eclipse.ui.views.properties.TextPropertyDescriptor
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.writeArray(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at java.util.ArrayList.writeObject(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at com.example.ui.PracticeEditor.createOutputStream(PracticeEditor.java:74)
at com.example.ui.PracticeEditor.doSave(PracticeEditor.java:101)
at org.eclipse.ui.internal.SaveableHelper$1.run(SaveableHelper.java:131)
at org.eclipse.ui.internal.SaveableHelper$4.run(SaveableHelper.java:252)
at org.eclipse.jface.operation.ModalContext.runInCurrentThread(ModalContext.java:369)
at org.eclipse.jface.operation.ModalContext.run(ModalContext.java:313)
at org.eclipse.jface.window.ApplicationWindow$1.run(ApplicationWindow.java:763)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
at org.eclipse.jface.window.ApplicationWindow.run(ApplicationWindow.java:760)
at org.eclipse.ui.internal.WorkbenchWindow.run(WorkbenchWindow.java:2283)
at org.eclipse.ui.internal.SaveableHelper.runProgressMonitorOperation(SaveableHelper.java:258)
at org.eclipse.ui.internal.SaveableHelper.savePart(SaveableHelper.java:136)
at org.eclipse.ui.internal.EditorManager.savePart(EditorManager.java:1386)
at org.eclipse.ui.internal.WorkbenchPage.savePart(WorkbenchPage.java:2995)
at org.eclipse.ui.internal.WorkbenchPage.saveEditor(WorkbenchPage.java:3008)
at org.eclipse.ui.internal.SaveAction.run(SaveAction.java:67)
at org.eclipse.jface.action.Action.runWithEvent(Action.java:499)
at org.eclipse.jface.commands.ActionHandler.execute(ActionHandler.java:119)
at org.eclipse.core.commands.Command.executeWithChecks(Command.java:461)
at org.eclipse.core.commands.ParameterizedCommand.executeWithChecks(ParameterizedCommand.java:424)
at org.eclipse.ui.internal.handlers.HandlerService.executeCommand(HandlerService.java:160)
at org.eclipse.ui.internal.keys.WorkbenchKeyboard.executeCommand(WorkbenchKeyboard.java:466)
at org.eclipse.ui.internal.keys.WorkbenchKeyboard.press(WorkbenchKeyboard.java:799)
at org.eclipse.ui.internal.keys.WorkbenchKeyboard.processKeyEvent(WorkbenchKeyboard.java:846)
at org.eclipse.ui.internal.keys.WorkbenchKeyboard.filterKeySequenceBindings(WorkbenchKeyboard.java:564)
at org.eclipse.ui.internal.keys.WorkbenchKeyboard.access$3(WorkbenchKeyboard.java:506)
at org.eclipse.ui.internal.keys.WorkbenchKeyboard$KeyDownFilter.handleEvent(WorkbenchKeyboard.java:122)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66)
at org.eclipse.swt.widgets.Display.filterEvent(Display.java:982)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:927)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:952)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:937)
at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:965)
at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:961)
at org.eclipse.swt.widgets.Widget.wmChar(Widget.java:1275)
at org.eclipse.swt.widgets.Control.WM_CHAR(Control.java:3346)
at org.eclipse.swt.widgets.Control.windowProc(Control.java:3246)
at org.eclipse.swt.widgets.Display.windowProc(Display.java:4025)
at org.eclipse.swt.internal.win32.OS.DispatchMessageW(Native Method)
at org.eclipse.swt.internal.win32.OS.DispatchMessage(OS.java:1925)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2966)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:1914)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:1878)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:419)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.IDEApplication.run(IDEApplication.java:95)
at org.eclipse.core.internal.runtime.PlatformActivator$1.run(PlatformActivator.java:78)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:92)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:68)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:400)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:177)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.core.launcher.Main.invokeFramework(Main.java:336)
at org.eclipse.core.launcher.Main.basicRun(Main.java:280)
at org.eclipse.core.launcher.Main.run(Main.java:977)
at org.eclipse.core.launcher.Main.main(Main.java:952)