@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.FIELD)
@Inherited
@Documented
public @interface MyAutowire {
}

public class TestController {

    @MyAutowire
    private TestService testService;

    public void testControllerMethod(){
        testService.testserviceMethod();
    }

}

public
 
 class TestService {

    public void testserviceMethod(){
        System.out.println("我是service");
    }
}

public class Test {

    public static void main(String[] args) {
        TestController testController=new TestController();
        Class clazz=testController.getClass();
        Field[] fields 
 
=clazz.getDeclaredFields();
        for(Field field:fields){
           Annotation annotation= field.getAnnotation(MyAutowire.class);
           if(annotation!=null){
               Class type=field.getType();
               try {
                   //必須設定為可訪問 否則會報錯
                   field.setAccessible(true
 
);
                   Object o=type.newInstance();
                   //拿到這個屬性 向物件的這個屬性設定值
                   field.set(testController,o);
               } catch (InstantiationException e) {
                   e.printStackTrace();
               } catch (IllegalAccessException e) {
                   e.printStackTrace();
               }
           }
        }
　　　　　　
　　　　　//可以成功輸出 service的列印的 我是service
        testController.testControllerMethod();
    }
}