Bug 5765 New Class button in empty workspace should be more supportive
User feedback: "Confused how to create my first project" We should be more supportive in the UI for this special case since it is a first time experience with the UI. Therefore when the workbench is empty we should offer to create a new Java project. Minimal solution is to show an info dialog that explains that user should create a project first and offer a button to open the Java project wizard. The same is true for the new package and new interface buttons.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/ContainerPage.java
public ContainerPage(String name, IWorkspaceRoot root) {
		super(name);
		fWorkspaceRoot= root;	
		ContainerFieldAdapter adapter= new ContainerFieldAdapter();
		
		fContainerDialogField= new StringButtonDialogField(adapter);
		fContainerDialogField.setDialogFieldListener(adapter);
		fContainerDialogField.setLabelText(NewWizardMessages.getString("ContainerPage.container.label")); 
		fContainerDialogField.setButtonLabel(NewWizardMessages.getString("ContainerPage.container.button")); 
		
		fContainerStatus= new StatusInfo();
		fCurrRoot= null;
	}
			
	/**
	 * Initializes the fields provided by the container page with a given
	 * Java element as selection.
	 * @param elem The initial selection of this page or null if no
	 *             selection was available
	 */
	protected void initContainerPage(IJavaElement elem) {
		IPackageFragmentRoot initRoot= null;
		if (elem != null) {
			initRoot= JavaModelUtil.getPackageFragmentRoot(elem);
			if (initRoot == null || initRoot.isArchive()) {
				IJavaProject jproject= elem.getJavaProject();
				try {
					initRoot= null;
					IPackageFragmentRoot[] roots= jproject.getPackageFragmentRoots();
					for (int i= 0; i < roots.length; i++) {