Bug 120544 [build path] Editing external source folder does not persist
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/BuildPathsBlock.java
updateUI();
	}
    	
	/*
	 * Creates the Java project and sets the configured build path and output location.
	 * If the project already exists only build paths are updated.
	 */
	public static void flush(List classPathEntries, IPath outputLocation, IProgressMonitor monitor) throws CoreException, OperationCanceledException {
		if (classPathEntries.isEmpty())
			return;
		
		if (monitor == null) {
			monitor= new NullProgressMonitor();
		}
		monitor.setTaskName(NewWizardMessages.BuildPathsBlock_operationdesc_java); 
		monitor.beginTask("", classPathEntries.size() + 4); 
		try {
			
			IJavaProject javaProject= ((CPListElement)classPathEntries.get(0)).getJavaProject();
			IProject project= javaProject.getProject();
			IPath projPath= project.getFullPath();
			
			IPath oldOutputLocation;
			try {
				oldOutputLocation= javaProject.getOutputLocation();		
			} catch (CoreException e) {
				oldOutputLocation= projPath.append(PreferenceConstants.getPreferenceStore().getString(PreferenceConstants.SRCBIN_BINNAME));
			}