Bug 27408 Preference convertor also maps to font registry
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/JavaPlugin.java
}
		
	private IWorkbenchPage internalGetActivePage() {
		IWorkbenchWindow window= getWorkbench().getActiveWorkbenchWindow();
		if (window == null)
			return null;
		return getWorkbench().getActiveWorkbenchWindow().getActivePage();
	}
		
	public synchronized CompilationUnitDocumentProvider getCompilationUnitDocumentProvider() {
		if (fCompilationUnitDocumentProvider == null)
			fCompilationUnitDocumentProvider= new CompilationUnitDocumentProvider();
		return fCompilationUnitDocumentProvider;
	}
	
	public synchronized ClassFileDocumentProvider getClassFileDocumentProvider() {
		if (fClassFileDocumentProvider == null)
			fClassFileDocumentProvider= new ClassFileDocumentProvider();
		return fClassFileDocumentProvider;
	}
	public synchronized IWorkingCopyManager getWorkingCopyManager() {
		return getCompilationUnitDocumentProvider();
	}
	
	public synchronized ProblemMarkerManager getProblemMarkerManager() {
		if (fProblemMarkerManager == null)
			fProblemMarkerManager= new ProblemMarkerManager();
		return fProblemMarkerManager;
	}