spring项目在启动的时候执行方法初始化

说明：老项目，使用的是spring 3项目，需要对接RocketMQ，配置完之后，在消费者监听方法中，发现业务处理service注入不进来，最后检查发现是因为消费者监听工具类没有被正确的初始化，所以它里边的业务service注入之后是个null，于是各种折腾，特此记录一下

方式一：

解决：对需要初始化的类实现InitializingBean接口，重写afterPropertiesSet()方法，在afterPropertiesSet方法中调用需要被初始化的方法

代码如下：

import xx.xxx.component.BaseServiceMqConsumer;
import xx.xxx.service.VideoConsumerService;
import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyStatus;
import org.apache.rocketmq.client.consumer.listener.MessageListenerConcurrently;
import org.apache.rocketmq.client.exception.MQClientException;
import org.apache.rocketmq.common.message.MessageExt;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.DependsOn;
import org.springframework.stereotype.Component;

import java.io.UnsupportedEncodingException;
import java.util.List;


@DependsOn("RocketMqConfig")
@Component
public class RocketMqConsumerUtil implements InitializingBean {     

    private static Logger log = LoggerFactory.getLogger(RocketMqConsumerUtil.class);

    @Autowired
    private VideoConsumerService videoConsumerService;

    /**
     * 接收消息
     */
    public void listener(){

        // 获取消息生产者
        DefaultMQPushConsumer consumer = BaseServiceMqConsumer.getDefaultMQPushConsumer();

        // 订阅主体
        try {
            consumer.subscribe(RocketMqUtil.topic, "*");

            consumer.registerMessageListener(new MessageListenerConcurrently() {

                /**
                 * * 默认msgs里只有一条消息，可以通过设置consumeMessageBatchMaxSize参数来批量接收消息
                 */
                public ConsumeConcurrentlyStatus consumeMessage(
                        List<MessageExt> msgs, ConsumeConcurrentlyContext context) {
                    MessageExt messageExt = msgs.get(0);
                    String msg = null;
                    try {
                        msg = new String(messageExt.getBody(),"utf-8");
                    } catch (UnsupportedEncodingException e) {
                        log.error("消息编码失败，MsgBody:{}",new String(messageExt.getBody()));
                        e.printStackTrace();
                    }
                      log.info("消费开始-MsgBody:{}",msg);
//                    String msg = new String(messageExt.getBody());
//                    log.info("MsgBody:{}",new String(messageExt.getBody()));

                    if (messageExt.getTopic().equals(RocketMqUtil.topic)) {
                        // topic的消费逻辑
                        if (messageExt.getTags() != null && messageExt.getTags().equals(RocketMqUtil.tag)) {
                            // 根据Tag消费消息，具体消费消息的业务方法
                            videoConsumerService.dealVideoMsg(msg);
                        }
                    } else if (messageExt.getTopic().equals("TopicTest2")) {
                        // 执行TopicTest2的消费逻辑
                    }

                    return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
                }
            });

            /**
             * Consumer对象在使用之前必须要调用start初始化，初始化一次即可<br>
             */
            consumer.start();
            log.info("rocketmq-consumer 启动成功---------------------------------------");
        } catch (MQClientException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        listener();//调用需要被初始化的方法
    }
}

方式二：

使用注解@PostContruct 指定需要被初始化执行的方法

package net.greatsoft.xxx.utils;

import xxx.xxx.component.BaseServiceMqConsumer;
import net.greatsoft.xxx.service.VideoConsumerService;
import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyStatus;
import org.apache.rocketmq.client.consumer.listener.MessageListenerConcurrently;
import org.apache.rocketmq.client.exception.MQClientException;
import org.apache.rocketmq.common.message.MessageExt;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.DependsOn;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import java.io.UnsupportedEncodingException;
import java.util.List;


@DependsOn("RocketMqConfig")
@Component
public class RocketMqConsumerUtil  {

    private static Logger log = LoggerFactory.getLogger(RocketMqConsumerUtil.class);

    @Autowired
    private VideoConsumerService videoConsumerService;

    /**
     * 接收消息8
     */
    @PostConstruct
    public void listener(){

        // 获取消息生产者
        DefaultMQPushConsumer consumer = BaseServiceMqConsumer.getDefaultMQPushConsumer();

        // 订阅主体
        try {
            consumer.subscribe(RocketMqUtil.topic, "*");

            consumer.registerMessageListener(new MessageListenerConcurrently() {

                /**
                 * * 默认msgs里只有一条消息，可以通过设置consumeMessageBatchMaxSize参数来批量接收消息
                 */
                public ConsumeConcurrentlyStatus consumeMessage(
                        List<MessageExt> msgs, ConsumeConcurrentlyContext context) {
                    MessageExt messageExt = msgs.get(0);
                    String msg = null;
                    try {
                        msg = new String(messageExt.getBody(),"utf-8");
                    } catch (UnsupportedEncodingException e) {
                        log.error("消息编码失败，MsgBody:{}",new String(messageExt.getBody()));
                        e.printStackTrace();
                    }
                    log.info("消费开始-MsgBody:{}",msg);
                    if (messageExt.getTopic().equals(RocketMqUtil.topic)) {
                        // topic的消费逻辑
                        if (messageExt.getTags() != null && messageExt.getTags().equals(RocketMqUtil.tag)) {
                            // 根据Tag消费消息，具体消费消息的业务方法
                            videoConsumerService.dealVideoMsg(msg);
                        }
                    } else if (messageExt.getTopic().equals("TopicTest2")) {
                        // 执行TopicTest2的消费逻辑
                    }

                    return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
                }
            });

            /**
             * Consumer对象在使用之前必须要调用start初始化，初始化一次即可<br>
             */
            consumer.start();
            log.info("rocketmq-consumer 启动成功---------------------------------------");
        } catch (MQClientException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }


}

方式三：

在spring的xml配置文件中使用 <Bean>的init 属性来执行初始化的Bean

    <bean id="rocketMqConsumerUtil" class="xx.xxx.utils.RocketMqConsumerUtil"
    scope="singleton" init-method="listener"/>

package net.greatsoft.jinNanHealth.utils;

import net.greatsoft.jinNanHealth.component.BaseServiceMqConsumer;
import net.greatsoft.jinNanHealth.service.VideoConsumerService;
import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyStatus;
import org.apache.rocketmq.client.consumer.listener.MessageListenerConcurrently;
import org.apache.rocketmq.client.exception.MQClientException;
import org.apache.rocketmq.common.message.MessageExt;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.DependsOn;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import java.io.UnsupportedEncodingException;
import java.util.List;

/**
 * @author xc
 * @date 2020-07-23
 */
@DependsOn("RocketMqUtil")
@Component
public class RocketMqConsumerUtil  {

    private static Logger log = LoggerFactory.getLogger(RocketMqConsumerUtil.class);

    @Autowired
    private VideoConsumerService videoConsumerService;

    /**
     * 接收消息8
     */
    public void listener(){

        // 获取消息生产者
        DefaultMQPushConsumer consumer = BaseServiceMqConsumer.getDefaultMQPushConsumer();

        // 订阅主体
        try {
            consumer.subscribe(RocketMqUtil.topic, "*");

            consumer.registerMessageListener(new MessageListenerConcurrently() {

                /**
                 * * 默认msgs里只有一条消息，可以通过设置consumeMessageBatchMaxSize参数来批量接收消息
                 */
                public ConsumeConcurrentlyStatus consumeMessage(
                        List<MessageExt> msgs, ConsumeConcurrentlyContext context) {
                    MessageExt messageExt = msgs.get(0);
                    String msg = null;
                    try {
                        msg = new String(messageExt.getBody(),"utf-8");
                    } catch (UnsupportedEncodingException e) {
                        log.error("消息编码失败，MsgBody:{}",new String(messageExt.getBody()));
                        e.printStackTrace();
                    }
 　　　　　　　　　　　 log.info("消费开始-MsgBody:{}",msg);
                    if (messageExt.getTopic().equals(RocketMqUtil.topic)) {
                        // topic的消费逻辑
                        if (messageExt.getTags() != null && messageExt.getTags().equals(RocketMqUtil.tag)) {
                            // 根据Tag消费消息，具体消费消息的业务方法
                            videoConsumerService.dealVideoMsg(msg);
                        }
                    } else if (messageExt.getTopic().equals("TopicTest2")) {
                        // 执行TopicTest2的消费逻辑
                    }

                    return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
                }
            });

            /**
             * Consumer对象在使用之前必须要调用start初始化，初始化一次即可<br>
             */
            consumer.start();
            log.info("rocketmq-consumer 启动成功---------------------------------------");
        } catch (MQClientException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }


}