Package org.dellroad.stuff.vaadin24.field

Annotation Interface AbstractFieldBuilder.FieldDefault

Enclosing class:

AbstractFieldBuilder<S extends AbstractFieldBuilder<S,T>,T>

@Retention(RUNTIME)
@Target(METHOD)
@Documented
public static @interface AbstractFieldBuilder.FieldDefault

Declare alternate default values for properties of the Vaadin fields created by @FieldBuilder.

A @FieldBuilder.FieldDefault annotation annotates a static method in an edited model class that returns an alternate default value for some field configuration property, for example, "itemLabelGenerator".

The property is specified by name and works for all Vaadin field types having a corresponding setter method whose parameter type is compatible with the annotated method's return type.

For example:

 // This is one of our data model classes
 public class Person {
     public String getFirstName() { ... }
     public String getLastName() { ... }

     @FieldBuilder.FieldDefault("itemLabelGenerator")
     private static ItemLabelGenerator<Person> itemLabel() {
         return person -> person.getLastName() + ", " + person.getFirstName();
     }
 }

 // This is a class we want to edit using FieldBuilder-generated fields
 public class Vehicle {

     @FieldBuilder.ComboBox          // Does not use any special ItemLabelGenerator
     public Model getModel() { ... }

     @FieldBuilder.ComboBox(         // Uses an instance of AnotherClass as ItemLabelGenerator
       itemLabelGenerator = AnotherClass.class)
     public Person getOwner() { ... }

     @FieldBuilder.ComboBox          // Uses ItemLabelGenerator from Person.itemLabel()
     public Person getOwner() { ... }

     @FieldBuilder.CheckboxGroup     // Uses ItemLabelGenerator from Person.itemLabel()
     public Person getPassengers() { ... }
 }
 

Details

The annotated method must be static, take zero parameters, and have a return type compatible with the named field property, or else the annotation is ignored. Public, package-private, protected, and private methods are supported.

These method may be declared in the edited model class, or any superclass thereof. If the same property is named by multiple methods, the method declared in the narrower declaring class wins. If neither declaring class is narrower, an exception is thrown.

These annotations only affect fields created from @FieldBuilder.Foo declarative annotations; fields returned by @FieldBuilder.ProvidesField methods are not affected.

Required Element Summary

Required Elements

Modifier and Type	Required Element	Description
String	value	The name of the field property that the annotated method will provide.

Element Details

value

String value

The name of the field property that the annotated method will provide.

Returns:

field property name