class PackageNameEditor<T extends HasPackageNameProperty> implements PropertyEditor<T>{

    public @Inject Injector injector;
    
    @Override
    public Stream<Item> fieldsFor(T document) {<FILL_FUNCTION_BODY>}    
}

        return Stream.of( 
            new DefaultTextFieldItem(
                "Package Name",
                document.defaultPackageNameProperty(injector),
                document.packageNameProperty(),
                "The package where generated classes will be located."
            )
        );
    
<no_super_class>