springmvc框架定时器功能实现和service注入问题解决

1、在SpringMVC配置文件中添加

xmlns:task="http://www.springframework.org/schema/task" 

http://www.springframework.org/schema/task  
http://www.springframework.org/schema/task/spring-task-3.2.xsd 

配置任务扫描

<task:annotation-driven />

配置扫描任务位置

<!-- 扫描任务 -->
    <context:component-scan base-package="com.vrveis.roundTrip.task" />

2、如果定时器方法单独写在一个工具类里，没有配置扫描该文件夹，注入service就会失败，可以通过SpringContextUtil类调用

具体代码如下：

package com.test.controller.base;
import org.apache.log4j.Logger;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

/**
 * 在Spring 注解中，普通类获取@Service标记的方法或者bean对象
 */
@Component
public class SpringContextUtil implements ApplicationContextAware {
    private static Logger logger = Logger.getLogger(SpringContextUtil.class);
    private static ApplicationContext applicationContext = null;

    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException
    {
        logger.info("------SpringContextUtil setApplicationContext-------");
        SpringContextUtil.applicationContext = applicationContext;
    }

    public static ApplicationContext getApplicationContext() {
        return applicationContext;
    }

    /**
     * 注意 bean name默认 = 类名(首字母小写)
     * 例如: A8sClusterDao = getBean("a8sClusterDao")
     * @param name
     * @return
     * @throws BeansException
     */
    public static Object getBean(String name) throws BeansException {
        return applicationContext.getBean(name);
    }

    /**
     * 根据类名获取到bean
     * @param <T>
     * @param clazz
     * @return
     * @throws BeansException
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBeanByName(Class<T> clazz) throws BeansException {
        try {
            char[] cs=clazz.getSimpleName().toCharArray();
            cs[0] += 32;//首字母大写到小写
            return (T) applicationContext.getBean(String.valueOf(cs));
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        } 
    }

    public static boolean containsBean(String name) {
        return applicationContext.containsBean(name);
    }

    public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException {
        return applicationContext.isSingleton(name);
    }

}

//获取 Bean  注意bean的首字母小写
   RcpqService rcpqService=(RcpqService) SpringContextUtil.getBean("rcpqService");

3、利用监听器，实现定时器功能：

在web.xml中设置监听器：

<listener>
    <listener-class>com.test.listener.MyTimerTaskListener</listener-class>
  </listener>

监听器代码如下：

package com.test.listener;

import java.util.Calendar;
import java.util.Timer;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import com.test.util.MyTimerTask;
/**
 * @author snwei
 */
public class MyTimerTaskListener implements ServletContextListener {
    private Timer timer = null;
    @Override
    public void contextDestroyed(ServletContextEvent arg0) {
        timer.cancel();
    }

    @Override
    public void contextInitialized(ServletContextEvent arg0) {
        System.out.println("-----开始启动定时器------");
        Calendar firstStart = Calendar.getInstance();
        firstStart.set(Calendar.HOUR_OF_DAY, 0);
        firstStart.set(Calendar.MINUTE, 10);
        firstStart.set(Calendar.SECOND, 0);
        timer = new Timer(true);
        //第一次是凌晨0:10:00执行，间隔24小时执行一次
        timer.schedule(new MyTimerTask(), firstStart.getTime(), 1000*60*60*24);
        
        //timer.scheduleAtFixedRate(task, delay, intevalPeriod);//严格按照调度时间来的,时间不会顺延
    	//timer.schedule(task, new Date(), intevalPeriod);//如果某一次调度时间比较长，那么后面的时间会顺延，保证调度间隔
        //timer.scheduleAtFixedRate(new MyTimerTask(), 0, 1000*60*10);  //测试
    }
}

package com.test.util;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.TimerTask;
import com.test.controller.base.SpringContextUtil;
import com.test.service.manager.rcpq.RcpqService;
/**
 * 定时器
 */
public class MyTimerTask extends TimerTask{
    @Override
    public void run() {
    	//获取 Bean
    	RcpqService rcpqService=(RcpqService) SpringContextUtil.getBean("rcpqService");
	//调用service方法，业务代码实现
	...
    }
}