（四）Feign面向接口调用

（四）Feign面向接口调用 改造api模块

依赖，因为要书写mvc和feign注解

	org.springframework.boot
	spring-boot-starter-web


	org.springframework.cloud
	spring-cloud-starter-feign
	1.4.7.RELEASE

添加一个接口，封装了生产者的对应路由和传参

@FeignClient("provider")
public interface ProviderA {
	@RequestMapping("/hello")
	public Student fun1(@RequestParam("count") Integer count);
}

改造生产者（可选）

让生产者继承这个接口

@RestController
public class HelloController implements ProviderA {
	@Override
	@RequestMapping("/hello")
	public Student fun1(Integer count) {
		System.out.println(count);
		return new Student("张三", 23);
	}
}

改造消费者

依赖

	org.springframework.cloud
	spring-cloud-starter-feign
	1.4.7.RELEASE

启动类，启用Feign扫描，指向api包

@SpringBootApplication
@EnableEurekaClient
@EnableFeignClients(basePackages = {"org.example.api.controller"})
public class App {
	public static void main(String[] args) {
		SpringApplication.run(App.class);
	}

	@Bean
	@LoadBalanced
	public RestTemplate restTemplate() {
		return new RestTemplate();
	}
}

控制器，用Feign替换RestTemplate

@RestController
public class HelloController {

	@Autowired
	private ProviderA providerA;
	private static Integer count = 1;

	@RequestMapping("/")
	public Student fun1() {
		return providerA.fun1(count++);
	}
}

测试

全部启动，打开URL：http://localhost:9101/

成功！