Hystrix Javanica回退在Spring Cloud 1.0中不起作用

Question

我基于@SpencerGibb feign-eureka spring cloud starter示例构建了一个超级简单的Hystrix短路示例。一开始，我以为我不能让hystrix javanica默认的fallbackMethod触发由于虚假…现在，除去feign，hystrix默认的fallbackMethod仍然不能捕获异常。

pom.xml

<parent>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-parent</artifactId>
    <version>1.0.0.RELEASE</version>
    <relativePath /> <!-- lookup parent from repository -->
</parent>

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <java.version>1.8</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-eureka</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-hystrix</artifactId>
    </dependency>
    :
</dependencies>

主文件：

@SpringBootApplication
@EnableDiscoveryClient
@EnableHystrix
@RestController
public class HelloClientApplication {

  @Autowired
  HelloClientComponent helloClientComponent;

  @RequestMapping("/")
  public String hello() {
    return helloClientComponent.makeMultipleCalls();
  }

  public static void main(String[] args) {
    SpringApplication.run(HelloClientApplication.class, args);
  }

java（创建HelloClientComponent.java是因为我知道javanica希望位于spring托管组件或服务中）：

@Component
public class HelloClientComponent {

@Autowired
RestTemplate restTemplate;

public String makeMultipleCalls() {
    int cnt=20;
    StringBuilder sb = new StringBuilder();
    while (cnt-- > 0) {
        String response = theServerRequestRoot();
        sb.append(response).append("  ");
    }
    return sb.toString();
}

public String theServersRequestRootFallback() {
    System.out.println("BOMB!!!!!!");
    return "BOMB!!!!!!";
}

@HystrixCommand(fallbackMethod = "theServersRequestRootFallback", commandKey = "callToServers")
public String theServerRequestRoot() {
        ResponseEntity<String> result = restTemplate.getForEntity("http://HelloServer", String.class);
        System.out.println(result.getBody());
        return result.getBody();
}
}

根据Spencer和Dave的建议更新解决方案。更改为以下内容：

主应用程序文件：

@SpringBootApplication
@EnableDiscoveryClient
@EnableHystrix
@RestController
public class HelloClientApplication {

  @Autowired
  HelloClientComponent helloClientComponent;

@RequestMapping("/")
public String hello() {
    int cnt=20;
    StringBuilder sb = new StringBuilder();
    while (cnt-- > 0) {
        String response = helloClientComponent.theServerRequestRoot();     // call directly to @Component in order for @HystrixCommand to intercept via AOP
        sb.append(response).append("  ");
    }
    return sb.toString();
}

  public static void main(String[] args) {
    SpringApplication.run(HelloClientApplication.class, args);
  }
  }

@Component
public class HelloClientComponent {

@Autowired
RestTemplate restTemplate;

public String theServersRequestRootFallback() {
    System.out.println("BOMB!!!!!!");
    return "BOMB!!!!!!";
}

@HystrixCommand(fallbackMethod = "theServersRequestRootFallback", commandKey = "callToServers")
public String theServerRequestRoot() {
        ResponseEntity<String> result = restTemplate.getForEntity("http://HelloServer", String.class);
        System.out.println(result.getBody());
        return result.getBody();
}
}