Bug 47922 Double-click does not go into resource folders [package explorer]
build I20031121 - In a self-hosting workspace with UI in source, - On the Java pref page, change the double-click behavior for the package explorer to Go Into. - In the Package Explorer, double-click on org.eclipse.ui. - It goes into the project. - Double-click on the schema folder. - It has no effect. It should go into it. - Choose Go Into from the context menu. - It goes into it OK
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerActionGroup.java
int size= selection.size();
		Object element= selection.getFirstElement();
		
		addGotoMenu(menu, element, size);
		
		addOpenNewWindowAction(menu, element);
		
		super.fillContextMenu(menu);
	}
	
	 private void addGotoMenu(IMenuManager menu, Object element, int size) {
		boolean enabled= size == 1 && fPart.getViewer().isExpandable(element) && (isGoIntoTarget(element) || element instanceof IContainer);
		fZoomInAction.setEnabled(enabled);
		if (enabled)
			menu.appendToGroup(IContextMenuConstants.GROUP_GOTO, fZoomInAction);
	}
	
	private boolean isGoIntoTarget(Object element) {
		if (element == null)
			return false;
		if (element instanceof IJavaElement) {
			int type= ((IJavaElement)element).getElementType();
			return type == IJavaElement.JAVA_PROJECT || 
				type == IJavaElement.PACKAGE_FRAGMENT_ROOT || 
				type == IJavaElement.PACKAGE_FRAGMENT;
		}
		return false;
	}
	private void addOpenNewWindowAction(IMenuManager menu, Object element) {
		if (element instanceof IJavaElement) {