Java tutorial
/** * Copyright 2012 Nikita Koksharov * * Licensed 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 com.corundumstudio.socketio.annotation; import java.lang.annotation.Annotation; import java.lang.reflect.Method; import java.util.Arrays; import java.util.List; import java.util.concurrent.atomic.AtomicBoolean; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.BeansException; import org.springframework.beans.factory.config.BeanPostProcessor; import org.springframework.util.ReflectionUtils; import org.springframework.util.ReflectionUtils.MethodCallback; import org.springframework.util.ReflectionUtils.MethodFilter; import com.corundumstudio.socketio.SocketIOServer; public class SpringAnnotationScanner implements BeanPostProcessor { private final Logger log = LoggerFactory.getLogger(getClass()); private final List<Class<? extends Annotation>> annotations = Arrays.asList(OnConnect.class, OnDisconnect.class, OnEvent.class); private final SocketIOServer socketIOServer; private Class originalBeanClass; public SpringAnnotationScanner(SocketIOServer socketIOServer) { super(); this.socketIOServer = socketIOServer; } @Override public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException { if (originalBeanClass != null) { socketIOServer.addListeners(bean, originalBeanClass); log.info("{} bean listeners added", beanName); originalBeanClass = null; } return bean; } @Override public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException { final AtomicBoolean add = new AtomicBoolean(); ReflectionUtils.doWithMethods(bean.getClass(), new MethodCallback() { @Override public void doWith(Method method) throws IllegalArgumentException, IllegalAccessException { add.set(true); } }, new MethodFilter() { @Override public boolean matches(Method method) { for (Class<? extends Annotation> annotationClass : annotations) { if (method.isAnnotationPresent(annotationClass)) { return true; } } return false; } }); if (add.get()) { originalBeanClass = bean.getClass(); } return bean; } }