springcloud报错-------关于 hystrix 的异常 FallbackDefinitionException:fallback method wasn't found

典型如下

第一种

import java.util.List;

@RestController
@RequestMapping("/order")
@DefaultProperties(defaultFallback = "fallback4Wait")
public class OrderController {

    @Autowired
private RestTemplate restTemplate;

@HystrixCommand(commandProperties = {
            @HystrixProperty(name="circuitBreaker.requestVolumeThreshold",value = "10"),
            @HystrixProperty(name = "circuitBreaker.sleepWindowInMilliseconds",value = "10000"),
            @HystrixProperty(name = "circuitBreaker.errorThresholdPercentage",value = "60")
    })
    @RequestMapping(value = "/buy/{id}",method = RequestMethod.GET)
    public Product findById(@PathVariable Long id){
        
if (id % 2 == 0 ) {
            throw  new RuntimeException("") ;
        }

        return restTemplate.getForObject("http://PRODUCT-SERVICE/product/"+ id,Product.class);

    }

    /**
     * 回退方法的返回值必须与调用者的方法要一致，参数也要完全一致
* @param id
* @return
*/
public Product fallback4Wait(){   // 此处应该没有参数  
        Product product = new Product();
        product.setProductName("当前服务访问压力过大，请稍后重试");
        return product;
    }
}

----------------------------------------

第二种

import java.util.List;

@RestController
@RequestMapping("/order")
@DefaultProperties(defaultFallback = "fallback4Wait")
public class OrderController {

    @Autowired
private RestTemplate restTemplate;

@Autowired
private DiscoveryClient discoveryClient; // 服务发现类

@HystrixCommand(fallbackMethod = "fallback4Wait")
    @RequestMapping(value = "/buy/{id}",method = RequestMethod.GET)
    public Product findById(@PathVariable Long id){

if (id % 2 == 0 ) {
            throw  new RuntimeException("") ;
        }

        return restTemplate.getForObject("http://PRODUCT-SERVICE/product/"+ id,Product.class);

    }

    /**
     * 回退方法的返回值必须与调用者的方法要一致，参数也要完全一致
* @param id
* @return
*/
public Product fallback4Wait(Long id){ // 此处有参数与上面一致
        Product product = new Product();
        product.setProductName("当前服务访问压力过大，请稍后重试");
        return product;
    }
}

1. @HystrixCommand(fallbackMethod = "fallbackHi")
2.  
   public String getHi(String x) {
3.  
   String msg = restTemplate.getForObject("http://jack/hi", String.class);
4.  
   return msg;
5.  
   }
6.  
    
7.  
   public String fallbackHi(){
8.  
   return "can't say hi";
9.