Bug 68011 [java search] "Search the JRE System Libraries" looks like a local preference but behaves as a global one... [search]
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/FindAction.java
private static final IJavaElement RETURN_WITHOUT_BEEP= JavaCore.create(JavaPlugin.getWorkspace().getRoot());
		
	private Class[] fValidTypes;
	private JavaEditor fEditor;	
	FindAction(IWorkbenchSite site) {
		super(site);
		fValidTypes= getValidTypes();
		init();
	}
	FindAction(JavaEditor editor) {
		this(editor.getEditorSite());
		fEditor= editor;
		setEnabled(SelectionConverter.canOperateOn(fEditor));
	}
	
	/**
	 * Called once by the constructors to initialize label, tooltip, image and help support of the action.
	 * To be overridden by implementors of this action.
	 */
	abstract void init();