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     */
016    package org.kuali.rice.kcb.util;
017    
018    import java.lang.reflect.InvocationHandler;
019    import java.lang.reflect.Method;
020    
021    import 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     */
028    public 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    }