Java tutorial
/* * Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.beans.beancontext; import java.util.Iterator; /** * <p> * One of the primary functions of a BeanContext is to act a as rendezvous * between JavaBeans, and BeanContextServiceProviders. * </p> * <p> * A JavaBean nested within a BeanContext, may ask that BeanContext to * provide an instance of a "service", based upon a reference to a Java * Class object that represents that service. * </p> * <p> * If such a service has been registered with the context, or one of its * nesting context's, in the case where a context delegate to its context * to satisfy a service request, then the BeanContextServiceProvider associated with * the service is asked to provide an instance of that service. * </p> * <p> * The ServcieProvider may always return the same instance, or it may * construct a new instance for each request. * </p> */ public interface BeanContextServiceProvider { /** * Invoked by {@code BeanContextServices}, this method * requests an instance of a * service from this {@code BeanContextServiceProvider}. * * @param bcs The {@code BeanContextServices} associated with this * particular request. This parameter enables the * {@code BeanContextServiceProvider} to distinguish service * requests from multiple sources. * * @param requestor The object requesting the service * * @param serviceClass The service requested * * @param serviceSelector the service dependent parameter * for a particular service, or {@code null} if not applicable. * * @return a reference to the requested service */ Object getService(BeanContextServices bcs, Object requestor, Class<?> serviceClass, Object serviceSelector); /** * Invoked by {@code BeanContextServices}, * this method releases a nested {@code BeanContextChild}'s * (or any arbitrary object associated with a * {@code BeanContextChild}) reference to the specified service. * * @param bcs the {@code BeanContextServices} associated with this * particular release request * * @param requestor the object requesting the service to be released * * @param service the service that is to be released */ public void releaseService(BeanContextServices bcs, Object requestor, Object service); /** * Invoked by {@code BeanContextServices}, this method * gets the current service selectors for the specified service. * A service selector is a service specific parameter, * typical examples of which could include: a * parameter to a constructor for the service implementation class, * a value for a particular service's property, or a key into a * map of existing implementations. * * @param bcs the {@code BeanContextServices} for this request * @param serviceClass the specified service * @return the current service selectors for the specified serviceClass */ Iterator<?> getCurrentServiceSelectors(BeanContextServices bcs, Class<?> serviceClass); }