geronimo-jcdi_2.0_spec/src/main/java/javax/enterprise/inject/spi/Producer.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 javax.enterprise.inject.spi;

import java.util.Set;

import javax.enterprise.context.spi.CreationalContext;

/**
 * Provides a generic operation for producing an instance of a type.
 * 
 * @version $Rev$ $Date$
 * 
 * <T> bean type
 */
public interface Producer<T> 
{
    /**
     * Its result depends on bean type.
     *
     * <p>
     *
     * <ul>
     *
     *     <li><b>Bean Class</b> : It calls the constructor annotated with {@link Initializer} if it
     * exists, or the constructor with no parameters otherwise.</li>
     *
     *  <li><b>Producer Method or Field</b> : Calls the producer method on,
     *  or accesses the producer field of, a contextual instance of the most
     *  specialized bean that specializes the bean that declares the producer method</li>
     *
     * </ul>
     *
     * </p>

     * @param creationalContext creational context
     *
     * @return an instance of bean
     */
    public T produce(CreationalContext<T> creationalContext);

    /**
     * Its result depends on bean type.
     * <p>
     * <ul>
     *     <li><b>Bean Class</b> : Does nothing.</li>
     *  <li><b>Producer Method</b> : Calls disposer method or any other cleanup.
     * </ul>
     * </p>
     *
     * @param instance dispose istance
     */
    public void dispose(T instance);

    /**
     * Its result depends on bean type.
     *
     * <p>
     *
     * <ul>
     *     <li><b>Bean Class</b> : Returns the set of InjectionPoint objects representing all injected fields,
     * bean constructor parameters and initializer method parameters.</li>
     *
     *  <li><b>Producer Method</b> : Returns the set of InjectionPoint objects
     *  representing all parameters of the producer method.</li>
     *
     * </ul>
     *
     * </p>
     *
     * @return set of injection points
     */
    public Set<InjectionPoint> getInjectionPoints();


}