解决SpringMvc中普通类注入Service为null的问题
时间：2022-09-22 10:39:56|栏目：JAVA代码|点击： 次
SpringMvc中普通类注入Service为null
场景：
使用Quartz定时器时,普通的java类需要注入spring的service类,在调用时报错!
解决方式：
/**
* 定时获取课程的service
*/
@Autowired
protected QuartzGetCourseService quartzGetCourseService = (QuartzGetCourseService) SpringContextUtil
.getBean("quartzGetCourseService");
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 ApplicationContext applicationContext = null;
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
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);
}
}
调用结束，测试可以获取Service.
spring之工具类使用service注入
一般需要在一个工具类中使用@Autowired 注解注入一个service。但是由于工具类方法一般都写成static，所以直接注入就存在问题。
栗子:
@Component
public class SmsController {
private static Logger logger = LoggerFactory.getLogger(SmsController.class);
@Autowired
private MessagesInfoService messagesInfoService;
private static SmsController smsController;
@PostConstruct
public void init() {
smsController = this;
smsController.messagesInfoService = this.messagesInfoService;
}
/**
*短信历史查询接口(查询某个时间段发送的短信)
*/
@RequestMapping(value = "/queryMessage",method = RequestMethod.GET)
public ModelAndView queryMessage{
pager = messagesInfoService.findPager(map,5,pIndex);
ModelAndView modelAndView = new ModelAndView("manage/jgdxgl/jgdx_qm");
List<MessagesInfo> list = pager.getItem();
modelAndView.addObject("pager",pager);
modelAndView.addObject("list",list);
return modelAndView
}
}
