2021-10-15

dubbo配置的filter，中注入 spring bean为 null

 解决：spring-dao的注入顺序要在dobbo filter之前

dubbo Filter中注入Spring 的Bean 三种方式：

方式一：dubbo通过setter方式自动注入

private TestService testService;
    
public void setTestService(TestService testService) {
    this.testService = testService;
}

方式二：通过ApplicationContext的方式来获取

可以自己先实现一个SpringUtil实现ApplicationContextAware接口，如下

@Component
public class SpringUtil implements ApplicationContextAware {
    private static ApplicationContext applicationContext;
 
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        if (SpringUtil.applicationContext == null) {
            SpringUtil.applicationContext = applicationContext;
        }
    }
 
    // 获取applicationContext
    public static ApplicationContext getApplicationContext() {
        return applicationContext;
    }
 
    // 通过name获取 Bean.
    public static Object getBean(String name) {
        return getApplicationContext().getBean(name);
    }
}

然后调用这个工具类来获取对象

TestService testService = (TestService) SpringUtil.getBean("testService");

方式三：使用ServiceBean

@Autowired
private ICallerRepository callerRepository;
...
//用dubbo提供的ServiceBean即可获取bean，因为该类已经实现了ApplicationContextAware
ApplicationContext context= ServiceBean.getSpringContext();
callerRepository = context.getBean(ICallerRepository.class);

参考：

**setter源码分析：**如何在filter等dubbo自管理组件中注入spring的bean - 简书