二、Spring Cloud 服务消费

爱被打了一巴掌 2021-10-30 07:06 220阅读 0赞

**关于getForEntity，postForEntity，分别提供了三个接口**

<T> ResponseEntity<T> getForEntity(String url, Class<T> responseType, Object... uriVariables)

<T> ResponseEntity<T> getForEntity(String url, Class<T> responseType, Map<String, ?> uriVariables)

<T> ResponseEntity<T> getForEntity(URI url, Class<T> responseType)
    
    参数说明

url：请求地址；

responseType：请求响应体body的包装类型；
    
    uriVariables：URL中的参数绑定
    
    
    <T> ResponseEntity<T> postForEntity(String url, @Nullable Object request, Class<T> responseType, Object... uriVariables)

<T> ResponseEntity<T> postForEntity(String url, @Nullable Object request, Class<T> responseType, Map<String, ?> uriVariables)

<T> ResponseEntity<T> postForEntity(URI url, @Nullable Object request, Class<T> responseType)

在上一节中，我们搭建了注册中心，服务提供者；

新建DemoController

package com.example.demo;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.http.ResponseEntity;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RequestParam;
    import org.springframework.web.bind.annotation.RestController;
    import org.springframework.web.client.RestTemplate;
    
    /**
     * @author: DevanYan
     * @create: 2019-05-21 16:39
     */
    @RestController
    public class DemoController {
    
        @Autowired
        RestTemplate restTemplate;
    
        @GetMapping("hello")
        public String hello(@RequestParam("name")String name){
    
            String url = "http://SERVER-ONE/hello?name=N"+Math.random();
            ResponseEntity<String> str = restTemplate.getForEntity(url,String.class);
            return  str.getBody();
        }
    }

启动项目，并访问http://localhost:8080/hello?name=jack

输出![871527-20190522094426880-139524772.png][]

**创建服务消费者SERVER-TWO**

①创建步骤同SERVER-ONE，端口是8090，具体步骤略；

②RestTemplate的使用

package com.example.demo;
    
    import ...
    
    
    @SpringBootApplication
    @EnableDiscoveryClient
    public class DemoApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(DemoApplication.class, args);
        }
    
        @Bean
        @LoadBalanced
        RestTemplate restTemplate(){
            return new RestTemplate();
        }
    
    }

③创建消费Controller

package com.example.demo;
    
    import ...
    
    /**
     * @author: DevanYan
     * @create: 2019-05-21 16:39
     */
    @RestController
    public class DemoController {
    
        @Autowired
        RestTemplate restTemplate;
    
        @GetMapping("hello")
        public String hello(@RequestParam("name")String name){
    
            String url = "http://SERVER-ONE/hello?name=N"+Math.random();
            ResponseEntity<String> str = restTemplate.getForEntity(url,String.class);
            return  str.getBody();
        }
    }

访问 http://localhost:8090/hello?name=jack

可看到server-one后台输出

![871527-20190522095059549-1841327146.png][]

转载于:https://www.cnblogs.com/devan/p/10904087.html

[871527-20190522094426880-139524772.png]: /images/20211029/7d91f6f35aa7474f9d8f6831daf1cc02.png
[871527-20190522095059549-1841327146.png]: /images/20211029/05c587f4955c43c0adf1ce6656801809.png