Bug 27264 opening/closing java files in presence of hiearchical package explorer is slow
will attach profiles
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageFragmentProvider.java
private TreeViewer fViewer;
	private boolean fFoldPackages;
	
	public PackageFragmentProvider() {
		fFoldPackages= arePackagesFoldedInHierarchicalLayout();
		JavaPlugin.getDefault().getPreferenceStore().addPropertyChangeListener(this);
	}
	
	/*
	 * @see org.eclipse.jface.viewers.ITreeContentProvider#getChildren(Object)
	 */
	public Object[] getChildren(Object parentElement) {
		try {
			if (parentElement instanceof IJavaElement) {
				IJavaElement iJavaElement= (IJavaElement) parentElement;
				int type= iJavaElement.getElementType();
				switch (type) {
					case IJavaElement.JAVA_PROJECT: {
						IJavaProject project= (IJavaProject)iJavaElement;
						IProject proj= project.getProject();					
												
						List children= new ArrayList();
						
						IPackageFragmentRoot defaultroot= project.getPackageFragmentRoot(proj);
						if(defaultroot.exists()){