001/*
002 * Copyright 2002-2012 the original author or authors.
003 *
004 * Licensed under the Apache 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 *      https://www.apache.org/licenses/LICENSE-2.0
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
017package org.springframework.aop.config;
018
019import java.lang.reflect.Method;
020
021import org.springframework.beans.BeanUtils;
022import org.springframework.beans.factory.BeanFactory;
023import org.springframework.beans.factory.BeanFactoryAware;
024import org.springframework.beans.factory.FactoryBean;
025import org.springframework.util.StringUtils;
026
027/**
028 * {@link FactoryBean} implementation that locates a {@link Method} on a specified bean.
029 *
030 * @author Rob Harrop
031 * @since 2.0
032 */
033public class MethodLocatingFactoryBean implements FactoryBean<Method>, BeanFactoryAware {
034
035        private String targetBeanName;
036
037        private String methodName;
038
039        private Method method;
040
041
042        /**
043         * Set the name of the bean to locate the {@link Method} on.
044         * <p>This property is required.
045         * @param targetBeanName the name of the bean to locate the {@link Method} on
046         */
047        public void setTargetBeanName(String targetBeanName) {
048                this.targetBeanName = targetBeanName;
049        }
050
051        /**
052         * Set the name of the {@link Method} to locate.
053         * <p>This property is required.
054         * @param methodName the name of the {@link Method} to locate
055         */
056        public void setMethodName(String methodName) {
057                this.methodName = methodName;
058        }
059
060        @Override
061        public void setBeanFactory(BeanFactory beanFactory) {
062                if (!StringUtils.hasText(this.targetBeanName)) {
063                        throw new IllegalArgumentException("Property 'targetBeanName' is required");
064                }
065                if (!StringUtils.hasText(this.methodName)) {
066                        throw new IllegalArgumentException("Property 'methodName' is required");
067                }
068
069                Class<?> beanClass = beanFactory.getType(this.targetBeanName);
070                if (beanClass == null) {
071                        throw new IllegalArgumentException("Can't determine type of bean with name '" + this.targetBeanName + "'");
072                }
073                this.method = BeanUtils.resolveSignature(this.methodName, beanClass);
074
075                if (this.method == null) {
076                        throw new IllegalArgumentException("Unable to locate method [" + this.methodName +
077                                        "] on bean [" + this.targetBeanName + "]");
078                }
079        }
080
081
082        @Override
083        public Method getObject() throws Exception {
084                return this.method;
085        }
086
087        @Override
088        public Class<Method> getObjectType() {
089                return Method.class;
090        }
091
092        @Override
093        public boolean isSingleton() {
094                return true;
095        }
096
097}