Bug 6579 Packages view: can't open MANIFEST.MF of JAR file
1. Drill into a JAR with a manifest file (MANIFEST.MF) in the Packages view. Note: The JAR must be on the build path. 2. Double-click MANIFEST.MF -> nothing happens 3. From the context menu select "Open" -> nothing happens I used ant.jar in org.eclipse.ant.core as my test case.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/EditorUtility.java
if (element != null && part instanceof JavaEditor) {
			((JavaEditor) part).setSelection(element);
		}
	}
	
	private static IEditorPart openInEditor(IFile file, boolean activate) throws PartInitException {
		if (file != null) {
			IWorkbenchPage p= JavaPlugin.getActivePage();
			if (p != null) {
				IEditorPart editorPart= IDE.openEditor(p, file, activate);
				initializeHighlightRange(editorPart);
				return editorPart;
			}
		}
		return null;
	}
	private static IEditorPart openInEditor(IEditorInput input, String editorID, boolean activate) throws PartInitException {
		if (input != null) {
			IWorkbenchPage p= JavaPlugin.getActivePage();
			if (p != null) {
				IEditorPart editorPart= p.openEditor(input, editorID, activate);
				initializeHighlightRange(editorPart);
				return editorPart;
			}
		}
		return null;
	}
	private static void initializeHighlightRange(IEditorPart editorPart) {
		if (editorPart instanceof ITextEditor) {
			TogglePresentationAction toggleAction= new TogglePresentationAction();