在Quartz的定时方法里引用@Autowired注入Bean，会报空指针错误

 

 

解决办法：

第一种方法：（推荐，简单，亲测可行）

使用@Resource(name="指定要注入的Bean")，代替@Autowired即可，指定了要注入的Bean名字，就能找到该Bean，就不会空指针了。

 

@Resource(name = "deviceStateProducerService")private DeviceStateProducerService deviceStateProducerService;

 

 

示例代码：

看下面红色字体部分

 代码

@Service("microDeviceStateService")public class MicroDeviceStateServiceImpl implements MicroDeviceStateService {        @Resource(name = "deviceStateProducerService")    private DeviceStateProducerService deviceStateProducerService;        @Scheduled(cron="0/10 * * *　* * ?")    @Lazy(false)    public void pingDeviceState() {        boolean isSuccess = PingUtils.ping("127.0.0.1", 4, 1000);        MicroDeviceState microDeviceState = new MicroDeviceState();        if(!isSuccess) {            logger.debug("连接设备状态失败!");            microDeviceState.setDeviceState("1");        }else {            microDeviceState.setDeviceState("0");        }                microDeviceState.setDeviceFlag("0");        microDeviceState.setIp("127.0.0.1");        DeviceStateBase deviceStateBase = new DeviceStateBase();        BeanUtils.copyProperties(microDeviceState, deviceStateBase);        deviceStateProducerService.deviceStateSender(deviceStateBase);    }        }

 有的定时器不生效，在类上加注解@EnableScheduling（spring自带的定时任务功能）

 

配置文件

 

 

 

 

 

第二种方法：（也可行，不推荐）

使用Spring原生获取Bean的方法 取代 @Autowired注入，同时，不要与定时方法在同一个类

 

示例代码：

注解方式写了一个定时方法，方法里需要引用Dao层，插入数据库，

直接@Autowired会报空指针异常，做出如下红色字体改动

public class FTPUtil{//    @Autowired//    MicroCameraPassRecordDao microCameraPassRecordDao;    private static MicroCameraPassRecordDao microCameraPassRecordDao = null;        使用Spring获取注入bean    static {        microCameraPassRecordDao =                 (MicroCameraPassRecordDao) SpringContextUtils.getApplicationContext().getBean("microCameraPassRecordDao");    }    /**    * 定时从FTP下载图片到本地，在这个方法里调用别的Dao层的方法    */    @Scheduled(cron="0/20 * * *　* * ?")    @Lazy(false)    public synchronized void service() {        FTPUtil ftpUtil = new FTPUtil();        boolean isConnect = ftpUtil.connectServer();        //从FTP下载到工程file下        boolean flag = ftpUtil.download(getFtpPath());                //引用注入Bean，插入数据库        MicroCameraPassRecord cameraRecord = new MicroCameraPassRecord();        cameraRecord.setCameraId(deviceID);        cameraRecord.setAddTime(System.currentTimeMillis());        microCameraPassRecordDao.insert(cameraRecord);            }    }

 getBean（引用类名，开头字母小写）

 

 

 SpringContextUtils

Spring获取Bean的工具类：

package com.zit.util;import java.util.Map;import org.springframework.beans.BeansException;import org.springframework.context.ApplicationContext;import org.springframework.context.ApplicationContextAware;import org.springframework.stereotype.Service;@SuppressWarnings({ "rawtypes", "unchecked" })@Service("springContextUtils")public class SpringContextUtils implements ApplicationContextAware {    private static ApplicationContext applicationContext;         public void setApplicationContext(ApplicationContext arg0)            throws BeansException {        applicationContext = arg0;    }     /**     * 获取applicationContext对象     * @return     */    public static ApplicationContext getApplicationContext(){        return applicationContext;    }         /**     * 根据bean的id来查找对象     * @param id     * @return     */    public static Object getBeanById(String id){        return applicationContext.getBean(id);    }         /**     * 根据bean的class来查找对象     * @param c     * @return     */    public static Object getBeanByClass(Class c){        return applicationContext.getBean(c);    }         /**     * 根据bean的class来查找所有的对象(包括子类)     * @param c     * @return     */    public static Map getBeansByClass(Class c){        return applicationContext.getBeansOfType(c);    }}