多线程不允许注入,注入null,之前是错误理解;
原因是new对象,不在spring容器中,new对象无法获取类的注入属性,一直是null
例子如下:
以下所有对象都是注入,没有new对象。
TestThreadAutowired 测试类通过注入MultiThreadClass (多线程类)对象,MultiThreadClass 多线程类中有注入Work类对象,Work类中也有注入。
public class TestThreadAutowired {
@Resource
private MultiThreadClass multiThreadClass ;
@Test
public void test() throws InterruptedException{
Thread thread = new Thread(multiThreadClass);
thread.start();
Thread.sleep(200000);
}
}
@Service
public class MultiThreadClass implements Runnable{
@Resource
Work work;
@Override
public void run() {
int i = 0;
while(i<5){
work.look();
}
}
}
@Service
public class Work {
@Resource
private DicService dicService;
public void look(){
System.out.println(dicService.getAllDicTRtkAcq());
}
}
对于可能有些情况,需要new 对象,然后调用的方法中用到注入的属性(注入失败,null),可以通过ApplcationContext获取spring容器中bean(实现ApplicationContextAware接口获取applicationContext)
方法如下:
@Service
public class SpringApplicationContextHolder implements ApplicationContextAware{
private static ApplicationContext context;
@Override
public void setApplicationContext(ApplicationContext applicationContext)
throws BeansException {
SpringApplicationContextHolder.context = applicationContext;
}
public static Object getSpringBean(String beanName) {
return context==null?null:context.getBean(beanName);
}
private static String[] getBeanDefinitionNames() {
return context.getBeanDefinitionNames();
}
}