使用OpenFeign实现服务调用的方法详解

<!-- eureka客户端依赖 -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
    <version>3.1.6</version>
</dependency>
<!-- springcloud-openfeign依赖 -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
    <version>3.1.7</version>
</dependency>

@FeignClient("myservice")
public interface HelloService {
    @GetMapping({"/hello4"})
    String hello(@RequestParam("name") String var1);
    @GetMapping({"/hello5"})
    String hello(@RequestHeader("name") String var1, @RequestHeader("age") int var2);
    @PostMapping({"/hello6"})
    String hello(@RequestBody User var1);
}

@RequestMapping(value = "/consumer2",method = RequestMethod.GET)
public String helloConsumer2(){
    StringBuilder sb = new StringBuilder();
    sb.append(helloService.hello("张三")).append("\n");
    sb.append(helloService.hello("张三",18)).append("\n");
    sb.append(helloService.hello(new User("张三",18))).append("\n");
    return sb.toString();
}

server.port=9001
spring.application.name=feign-consumer
eureka.client.service-url.defaultZone=http://peer1:1111/eureka/

@EnableFeignClients
@EnableDiscoveryClient
@SpringBootApplication
public class FeignConsumerApplication {
	public static void main(String[] args) {
		SpringApplication.run(FeignConsumerApplication.class, args);
	}
}

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
        <version>2.7.0</version>
    </dependency>
</dependencies>

@Component
public interface HelloService {
    @GetMapping("/hello4")
    String hello(@RequestParam("name") String name);
    @GetMapping("/hello5")
    String hello(@RequestHeader("name") String name,@RequestHeader("age") int age);
    @PostMapping("/hello6")
    String hello(@RequestBody User user);
}

public class User {
    private String name;
    private int age;
    public User(){}
    public User(String name,int age){
        this.name = name;
        this.age = age;
    }
    /** 省略get、set、toString方法 */
}

@RestController
public class ClientController implements HelloService {
    @Override
    public String hello(String name) {
        return name;
    }
    @Override
    public String hello(String name, int age) {
        return name+"|"+age;
    }
    @Override
    public String hello(User user) {
        return user.getName()+"|"+user.getAge();
    }
}

@FeignClient("myservice")
public interface HelloServiceDidi extends com.didi.service.HelloService {
}

@RequestMapping(value = "/consumer2",method = RequestMethod.GET)
public String helloConsumer2(){
    StringBuilder sb = new StringBuilder();
    sb.append(helloServiceDidi.hello("张三")).append("\n");
    sb.append(helloServiceDidi.hello("张三",18)).append("\n");
    sb.append(helloServiceDidi.hello(new User("张三",18))).append("\n");
    return sb.toString();
}