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
}
			}
		}
		return null;	
	}
	
	/** 
	 * Gets the working copy of an compilation unit opened in an editor
	 * @param part the editor part
	 * @param cu the original compilation unit (or another working copy)
	 * @return the working copy of the compilation unit, or null if not found
	 */	
	public static ICompilationUnit getWorkingCopy(ICompilationUnit cu) {
		if (cu == null)
			return null;
		if (cu.isWorkingCopy())
			return cu;
			
		return (ICompilationUnit)cu.findSharedWorkingCopy(JavaUI.getBufferFactory());
	}
	
	/** 
	 * Gets the working copy of an member opened in an editor
	 *
	 * @param member the original member or a member in a working copy
	 * @return the corresponding member in the shared working copy or <code>null</code> if not found
	 */	
	public static IMember getWorkingCopy(IMember member) throws JavaModelException {
		ICompilationUnit cu= member.getCompilationUnit();
		if (cu != null) {