Bug 9304 new class wizard: incorrect terminology used
1. new class wizard 2. press Add.. in interfaces 3. the dialog you see has a title 'Extended Interfaces Selection' this is incorrect - it should be 'Implemented Interfaces Selection' (this bug was pointed out on the wsad newsgroup)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/TypePage.java
*/
	protected IStatus typeNameChanged() {
		StatusInfo status= new StatusInfo();
		String typeName= getTypeName();
		
		if (typeName.length() == 0) {
			status.setError(NewWizardMessages.getString("TypePage.error.EnterTypeName")); 
			return status;
		}
		if (typeName.indexOf('.') != -1) {
			status.setError(NewWizardMessages.getString("TypePage.error.QualifiedName")); 
			return status;
		}
		IStatus val= JavaConventions.validateJavaTypeName(typeName);
		if (val.getSeverity() == IStatus.ERROR) {
			status.setError(NewWizardMessages.getFormattedString("TypePage.error.InvalidTypeName", val.getMessage())); 
			return status;
		} else if (val.getSeverity() == IStatus.WARNING) {
			status.setWarning(NewWizardMessages.getFormattedString("TypePage.warning.TypeNameDiscouraged", val.getMessage())); 
			
		}		
		
		if (!isEnclosingTypeSelected()) {
			IPackageFragment pack= getPackageFragment();
			if (pack != null) {
				ICompilationUnit cu= pack.getCompilationUnit(typeName + ".java"); 
				if (cu.exists()) {
					status.setError(NewWizardMessages.getString("TypePage.error.TypeNameExists")); 
					return status;
				}