1、概念
（1）概述
Feign是一个声明式的Web服务客户端，使得编写Web服务客户端变得非常容易，只需要创建一个接口，然后在上面添加注解即可。
2、Feign工程构建
（1）模仿消费者（80）新建一个Feign模块，并添加Feign的依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-feign</artifactId>
</dependency>
（2）修改公共模块
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-feign</artifactId>
</dependency>
注解的参数中带有微服务的名称，通过该名称获取服务
@FeignClient(value = "PROVIDER") public interface DeptClientService { @RequestMapping(value = "/dept/get/{id}",method = RequestMethod.GET) public Dept get(@PathVariable("id") long id); @RequestMapping(value = "/dept/list",method = RequestMethod.GET) public List<Dept> list(); @RequestMapping(value = "/dept/add",method = RequestMethod.POST) public boolean add(Dept dept); }
（3）创建消费者模块
@RestController public class DeptConsumerController { @Autowired private DeptClientService service = null; @RequestMapping(value = "/consumer/dept/get/{id}") public Dept get(@PathVariable("id") Long id) { return this.service.get(id); } @RequestMapping(value = "/consumer/dept/list") public List<Dept> list() { return this.service.list(); } @RequestMapping(value = "/consumer/dept/add") public Object add(Dept dept) { return this.service.add(dept); } }
@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class,HibernateJpaAutoConfiguration.class})
@EnableEurekaClient
@EnableFeignClients(basePackages= {"com.zhb"})
@ComponentScan("com.zhb")
public class DeptConsumer80_Feign_App {
public static void main(String[] args) {
SpringApplication.run(DeptConsumer80_Feign_App.class,args);
}
}
（4）RestTemplate 方式
消费者模块代码：
与Feign相比，RestTemplate 方式不需要在公共类里面添加接口，Feign是在接口里面的注解添加微服务的名称即可。
@RestController public class DeptConsumerController { private static final String REST_URL_PREFIX = "http://PROVIDER"; @Autowired private RestTemplate restTemplate; @RequestMapping(value = "/consumer/dept/add") public boolean add(Dept dept) { return restTemplate.postForObject(REST_URL_PREFIX + "/dept/add", dept, Boolean.class); } @RequestMapping(value = "/consumer/dept/get/{id}") public Dept get(@PathVariable("id") Long id) { return restTemplate.getForObject(REST_URL_PREFIX + "/dept/get/" + id, Dept.class); } @SuppressWarnings("unchecked") @RequestMapping(value = "/consumer/dept/list") public List<Dept> list() { return restTemplate.getForObject(REST_URL_PREFIX + "/dept/list", List.class); } }
配置类：
@Bean @LoadBalanced public RestTemplate template(){ return new RestTemplate(); }
原文：https://www.cnblogs.com/zhai1997/p/14224340.html