Bug 55884 Loading a user library from file does not warn when overwriting an existing library [build path]
Works in I2004032400010 + plug-in export for I200403240800 Add library 'mylib'. Save it. Change it. Load library from file. ==> should warn that 'mylib' gets changed.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/UserLibraryPreferencePage.java
return null;
		}
		String[] fileNames= dialog.getFileNames();
		int nChosen= fileNames.length;
			
		IPath filterPath= new Path(dialog.getFilterPath());
		CPListElement[] elems= new CPListElement[nChosen];
		for (int i= 0; i < nChosen; i++) {
			IPath path= filterPath.append(fileNames[i]).makeAbsolute();	
			CPListElement curr= new CPListElement(parent, null, IClasspathEntry.CPE_LIBRARY, path, null);
			curr.setAttribute(CPListElement.SOURCEATTACHMENT, BuildPathSupport.guessSourceAttachment(curr));
			curr.setAttribute(CPListElement.JAVADOC, JavaUI.getLibraryJavadocLocation(curr.getPath()));
			elems[i]= curr;
		}
		fDialogSettings.put(IUIConstants.DIALOGSTORE_LASTEXTJAR, filterPath.toOSString());
		
		return elems;
	}
	
	private class UserLibraryAdapter implements ITreeListAdapter {
		
		private final Object[] EMPTY= new Object[0];
		public void customButtonPressed(TreeListDialogField field, int index) {
			doCustomButtonPressed(field, index);
		}
		public void selectionChanged(TreeListDialogField field) {
			doSelectionChanged(field);
		}
		
		public void doubleClicked(TreeListDialogField field) {