服务发现RestTemplate和Feign

1.RestTemplate三种方式使用

①    直接使用RestTemplate，固定URL  @GetMapping("/say")     public String say(){         RestTemplate restTemplate = new RestTemplate();         String str = restTemplate.getForObject("http://localhost:8081/hello",String.class);         return "say "+str;     }

②    注入LoadBalancerClient通过应用名获取URL     @Autowired     private LoadBalancerClient loadBalancerClient;     @GetMapping("/say")     public String say(){         ServiceInstance serviceInstance = loadBalancerClient.choose("CLIENT");         RestTemplate restTemplate = new RestTemplate();         String url = String.format("http://%s:%s/hello",serviceInstance.getHost(),serviceInstance.getPort());         String str = restTemplate.getForObject(url,String.class);     }

③配置RestTemplate，URL直接使用应用名     @Component     public class RestTemplateConfig {         @Bean         @LoadBalanced         public RestTemplate restTemplate(){             return  new RestTemplate();         }     } -----------------------------------------------------------------------------------------------------------------------------     @Autowired     private RestTemplate restTemplate;     @GetMapping("/say")     public String say(){         String response = restTemplate.getForObject("http://CLIENT/hello",String.class);         return "say "+response;     }

2.使用Feign

①    配置注解@EnableFeignClients @SpringBootApplication @EnableDiscoveryClient @EnableFeignClients public class DemoApplication { public static void main(String[] args) { SpringApplication.run(DemoApplication.class, args); } } ②配置接口   @Autowired     HelloClient client;     @GetMapping("/say")     public String say(){         String response = client.hello();         return "say "+response;     }     @FeignClient("client")     interface HelloClient {         @GetMapping("/hello")         String hello();     }