001/**
002 * Copyright 2005-2014 The Kuali Foundation
003 *
004 * Licensed under the Educational Community License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.opensource.org/licenses/ecl2.php
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.kuali.rice.kcb.util;
017
018import java.lang.reflect.InvocationHandler;
019import java.lang.reflect.Method;
020
021import org.springframework.beans.factory.BeanFactory;
022
023/**
024 * Maps accessor invocations to beans in a BeanFactory. 
025 * @author Kuali Rice Team (rice.collab@kuali.org)
026 *
027 */
028public class BeanFactoryInvocationHandler implements InvocationHandler {
029     private static final String PREFIX = "get";
030
031     private BeanFactory beanFactory;
032     
033     public BeanFactoryInvocationHandler(BeanFactory beanFactory) {
034         this.beanFactory = beanFactory;
035     }
036
037     public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
038         if (args != null && args.length > 0) {
039             throw new RuntimeException("BeanFactoryInvocationHandler only serves getters");
040         }
041         String methodName = method.getName();
042         if (!methodName.startsWith(PREFIX)) {
043             throw new RuntimeException("BeanFactoryInvocationHandler only serves getters");
044         }
045         String beanName = methodName.substring(PREFIX.length());
046         if (beanName.length() == 0) {
047             throw new RuntimeException("Illegal accessor, no bean name specified: " + methodName);
048         }
049         char firstChar = beanName.charAt(0);
050         if (!Character.isLowerCase(firstChar)) {
051             beanName = Character.toLowerCase(firstChar) + beanName.substring(1);
052         }
053         return beanFactory.getBean(beanName);
054     }
055}