jakarta.enterprise.inject.Produces Maven / Gradle / Ivy
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/*
* Copyright 2010, Red Hat, Inc., and individual contributors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package jakarta.enterprise.inject;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import jakarta.enterprise.context.Dependent;
/**
*
*
* Identifies a producer method or field. May be applied to a method or field of a bean class.
*
*
*
* A producer method must be a non-abstract method of a managed bean class or session bean class. A producer method may be
* either static or non-static. If the bean is a session bean, the producer method must be either a business method of the EJB
* or a static method of the bean class.
*
*
*
* public class Shop {
* @Produces @ApplicationScoped
* @Catalog @Named("catalog")
* List<Product> getProducts() { ... }
* ...
* }
*
*
*
* A producer field must be a field of a managed bean class or session bean class. A producer field may be either static or
* non-static. If the bean is a session bean, the producer field must be a static field of the bean class.
*
*
*
* public class Shop {
* @Produces @ApplicationScoped
* @Catalog @Named("catalog")
* List<Product> products = ...;
* ...
* }
*
*
*
* If a producer method sometimes returns a null value, or if a producer field sometimes contains a null value when accessed,
* then the producer method or field must have scope {@link Dependent @Dependent}.
*
*
*
* A producer method return type or producer field type may not be a type variable.
*
*
*
* If the producer method return type or producer field type is a parameterized type, it must specify an actual type parameter
* or type variable for each type parameter.
*
*
*
* If the producer method return type or producer field type is a parameterized type with a type variable, it must have scope
* {@link Dependent @Dependent}.
*
*
*
* A producer method may have any number of parameters. All producer method parameters are injection points.
*
*
*
* public class OrderFactory {
*
* @Produces
* @ConversationScoped
* public Order createCurrentOrder(Shop shop, @Selected Product product) {
* Order order = new Order(product, shop);
* return order;
* }
*
* }
*
*
*
* A bean may declare multiple producer methods or fields.
*
*
*
* Producer methods and fields are not inherited by bean subclasses.
*
*
*
* Interceptors and decorators may not declare producer methods or fields.
*
*
* @see Disposes @Disposes
*
* @author Gavin King
* @author Pete Muir
*/
@Target({ METHOD, FIELD })
@Retention(RUNTIME)
@Documented
public @interface Produces {
}