Bug 5449 TVT Text Expansion/Truncations in new java class dialog
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/TypePage.java
if (root != null) {
			List elements= fSuperInterfacesDialogField.getElements();
			int nElements= elements.size();
			for (int i= 0; i < nElements; i++) {
				String intfname= (String)elements.get(i);
				try {
					IType type= JavaModelUtil.findType(root.getJavaProject(), intfname);
					if (type == null) {
						status.setWarning(NewWizardMessages.getFormattedString("TypePage.warning.InterfaceNotExists", intfname)); 
						return status;
					} else {
						if (type.isClass()) {
							status.setWarning(NewWizardMessages.getFormattedString("TypePage.warning.InterfaceIsNotInterface", intfname)); 
							return status;
						}
						if (!JavaModelUtil.isVisible(type, getPackageFragment())) {
							status.setWarning(NewWizardMessages.getFormattedString("TypePage.warning.InterfaceIsNotVisible", intfname)); 
							return status;
						}
					}
				} catch (JavaModelException e) {
					JavaPlugin.log(e.getStatus());
					
				}					
			}				
		}
		return status;
	}
	/**
	 * Called when the modifiers have changed.