Bug 117071 MembersOrderPreferenceCache leaking a propertyChangeListener
20051109 org.eclipse.jdt.ui.PreferenceConstants#initializeDefaultValues adds a listener to JDT UI preference store but this is not deleted before shutdown.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/JavaPlugin.java
return getWorkbench().getActiveWorkbenchWindow().getActivePage();
	}
	
	/**
	 * @deprecated
	 */
	public synchronized org.eclipse.jdt.core.IBufferFactory getBufferFactory() {
		if (fBufferFactory == null)
			fBufferFactory= new org.eclipse.jdt.internal.ui.javaeditor.CustomBufferFactory();
		return fBufferFactory;
	}
	
	public synchronized ICompilationUnitDocumentProvider getCompilationUnitDocumentProvider() {
		if (fCompilationUnitDocumentProvider == null)
			fCompilationUnitDocumentProvider= new CompilationUnitDocumentProvider();
		return fCompilationUnitDocumentProvider;
	}
	
	/**
	 * Returns the shared document provider for Java properties files
	 * used by this plug-in instance.  
	 * 
	 * @return the shared document provider for Java properties files
	 * @since 3.1
	 */
	public synchronized IDocumentProvider getPropertiesFileDocumentProvider() {
		if (fPropertiesFileDocumentProvider == null)
			fPropertiesFileDocumentProvider= new PropertiesFileDocumentProvider();
		return fPropertiesFileDocumentProvider;
	}