Bug 38458 enhance 'remove from classpath' [reorg] [ccp]
20030604 No delete offered on external JAR's: It could ask to remove them from the class path
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/RemoveFromClasspathAction.java
private static boolean checkEnabled(IStructuredSelection selection) {
		if (selection.isEmpty())
			return false;
		for (Iterator iter= selection.iterator(); iter.hasNext();) {
			if (! canRemove(iter.next()))
				return false;
		}
		return true;
	}
	
	/* (non-Javadoc)
	 * Method declared in SelectionDispatchAction
	 */
	public void run(final IStructuredSelection selection) {
		try {
			PlatformUI.getWorkbench().getActiveWorkbenchWindow().run(true, true, new WorkbenchRunnableAdapter(new IWorkspaceRunnable() {
				public void run(IProgressMonitor pm) throws CoreException {
					try{
						IPackageFragmentRoot[] roots= getRootsToRemove(selection);
						pm.beginTask(ActionMessages.getString("RemoveFromClasspathAction.Removing"), roots.length); 
						for (int i= 0; i < roots.length; i++) {
							int jCoreFlags= IPackageFragmentRoot.NO_RESOURCE_MODIFICATION | IPackageFragmentRoot.ORIGINATING_PROJECT_CLASSPATH;
							roots[i].delete(IResource.NONE, jCoreFlags, new SubProgressMonitor(pm, 1));
						}
					} finally {
						pm.done();
					}
				}
		}));