Bug 13034 Cannot create a Source Folder in a new Java Project
build 20020404 If you try and create a Source Folder in a Java Project you have just created you get an error preventing you from hitting finish. STEPS 1) Create Java Project Foo 2) Open New->Source Folder 3) Enter Bar as the name - you will get "Cannot nest entry Bar inside entry Foo/Bar" 4) Create a folder Bar. 5) Add it as a source folder in the Properties Dialog for Foo. No problem.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/BuildPathsBlock.java
if (fSWTWidget != null) {
			return fSWTWidget.getShell();
		}
		return JavaPlugin.getActiveWorkbenchShell();
	}
	
	
	/**
	 * Initializes the classpath for the given project. Multiple calls to init are allowed,
	 * but all existing settings will be cleared and replace by the given or default paths.
	 * @param project The java project to configure. Does not have to exist.
	 * @param outputLocation The output location to be set in the page. If <code>null</code>
	 * is passed, jdt default settings are used, or - if the project is an existing Java project- the
	 * output location of the existing project 
	 * @param classpathEntries The classpath entries to be set in the page. If <code>null</code>
	 * is passed, jdt default settings are used, or - if the project is an existing Java project - the
	 * classpath entries of the existing project
	 */	
	public void init(IJavaProject jproject, IPath outputLocation, IClasspathEntry[] classpathEntries) {
		fCurrJProject= jproject;
		boolean projectExists= false;
		try {
			IProject project= fCurrJProject.getProject();
			projectExists= (project.exists() && project.getFile(".classpath").exists()); 
			if  (projectExists) {
				if (outputLocation == null) {
					outputLocation=  fCurrJProject.getOutputLocation();
				}
				if (classpathEntries == null) {
					classpathEntries=  fCurrJProject.getRawClasspath();