Bug 72024 UndoManager creates potential memory leak [refactoring]
3.0 The refactoring undo manager doesn't call dispose in all cases where a undo/redo object is no longer needed. This can result in a memory leak since the undo/redo object could register for listeners and therefore relies on the fact the dispose is called correctly. Cases where dispose isn't called: - if the undo stack reaches it maximum number of change objects and the last one is removed from the stack. - if the undo/redo stack gests flushed and one of the change objects causes an exception during sending dispose. - if the undo/redo object isn't valid anymore and can therefore not be executed.
org.eclipse.ltk.ui.refactoring/src/org/eclipse/ltk/ui/refactoring/RefactoringWizard.java
public final boolean internalIsYesNoStyle(InternalAPI api) {
		Assert.isNotNull(api);
		return (fFlags & YES_NO_BUTTON_STYLE) != 0;
	}
	
	/**
	 * Note: This method is for internal use only. Clients are not allowed to call this method.
	 * 
	 * @param api internal instance to avoid access from external clients
	 * 
	 * @return whether the first node of the preview is supposed to be expanded
	 */
	public final boolean internalGetExpandFirstNode(InternalAPI api) {
		Assert.isNotNull(api);
		return (fFlags & PREVIEW_EXPAND_FIRST_NODE) != 0;
	}
	
	/**
	 * Note: This method is for internal use only. Clients are not allowed to call this method.
	 * 
	 * @param api internal instance to avoid access from external clients
	 * @param change the change to set
	 */
	public final void internalSetChange(InternalAPI api, Change change){
		Assert.isNotNull(api);
		IPreviewWizardPage page= (IPreviewWizardPage)getPage(IPreviewWizardPage.PAGE_NAME);
		if (page != null)
			page.setChange(change);
		fChange= change;
	}