RestTemplate 是springweb组建

作为Spring Cloud的子项目之一，Spring Cloud OpenFeign 是一种声明式、模板化的 HTTP 客户端，在 Spring Cloud 中使用 OpenFeign，可以做到使用 HTTP请求远程服务时能与调用本地方法一样的编码体验，开发者完全感知不到这是远程方法，更感知不到这是个 HTTP 请求。同时OpenFeign通过集成Ribbon实现客户端的负载均衡

nacos-server : 注册中心，解决是服务的注册与发现

Ribbon：客户端负载均衡器，解决的是服务集群负载均衡的问题

OpenFeign：声明式 HTTP 客户端 、代替Resttemplate组件，实现远程调用

演示案例说明

订单跟积分    订单的增删改影响积分增删改

新建积分微服务

pom依赖

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
    </dependencies>

 

application.properties

spring:
  application:
    name: integral
  cloud:
    nacos:
      discovery:
        server-addr: 192.168.59.12:8848,192.168.59.12:8858,192.168.59.12:8868
        username: nacos
        password: nacos



server:
  port: 9003

启动类

@SpringBootApplication
@EnableDiscoveryClient
public class IntegralApplication {

    public static void main(String[] args) {
        SpringApplication.run(IntegralApplication.class, args);
    }

}

暴露接口

@RestController
@RequestMapping("/integral")
public class IntegralController {


    @RequestMapping("/save")
    public Map save(@RequestBody Integral integral){
        System.out.println(integral);
        Map<String, Object> map = new HashMap<>();
        map.put("status",0);
        map.put("msg","添加成功");
        return map;
    }

    @RequestMapping("/update")
    public Map update(@RequestBody Integral integral){
        System.out.println(integral);

        HashMap<String, Object> map = new HashMap<>();
        map.put("status",0);
        map.put("msg","修改成功");
        return map;

    }


    @RequestMapping("/{id}")
    public Map deleteById(@PathVariable("id") Integer id){

        System.out.println("积分:"+id+"已经删除");

        HashMap<String, Object> map = new HashMap<>();
        map.put("status",0);
        map.put("msg","删除成功");
        return map;
    }

    @RequestMapping("/getOne")
    public Integral getOne(Integer id){

        System.out.println("查询的id为"+id+"积分对象");

        Integral integral = new Integral();

        integral.setId(id);
        integral.setType("会员积分");
        integral.setCount(500);

        return integral;
    }

    @RequestMapping("/getByCondition")
    public Integral getByCondition(Integer id,String type){

        System.out.println("id"+id);
        System.out.println("type"+type);

        Integral integral = new Integral();
        integral.setCount(8000);
        integral.setType(type);
        integral.setId(id);
        return integral;
    }
    
    @RequestMapping("/getAll")
    public List<Integral> getAll(){

        Integral integral = new Integral();
        integral.setId(1);
        integral.setCount(800);
        integral.setType("bb");

        Integral integral1 = new Integral();
        integral.setId(1);
        integral.setCount(900);
        integral.setType("aa");

        Integral integral2 = new Integral();
        integral.setId(1);
        integral.setCount(100);
        integral.setType("cc");

        List<Integral> integrals = Arrays.asList(integral, integral1, integral2);
        return integrals;

    }
}

实体类

实体类放在common 项目里  通过依赖引用

 

 

public class Integral {

    private Integer id;
    private Integer count;
    private String type;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public Integer getCount() {
        return count;
    }

    public void setCount(Integer count) {
        this.count = count;
    }

    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    }

    @Override
    public String toString() {
        return "Integral{" +
                "id=" + id +
                ", count=" + count +
                ", type='" + type + '\'' +
                '}';
    }
}

 

 

Openfeign使用

openfeign依赖 在order项目使用

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>

 1.在order的启动类增加@EnableFeignClients  开启Openfeign   并且指定扫描哪里

 

 2.写接口声明

@FeignClient  写了接口声明  指定是哪个暴露接口

这里是一个接口  方法名跟路径 参数等 要跟积分暴露接口里的完全一致

注意：这里如果参数时对象 要加@RequestBody注解

           是路径参数{id}类似要加@PathVariable注解  delete/1

           是参数kv形式的加@RwquestParam注解   ?id=1&&name=张三

 

@FeignClient("integral")
@RequestMapping("/integral")
public interface IntegralApi {

    @RequestMapping("/save")
    public Map save(@RequestBody  Integral integral);

    @RequestMapping("/update")
    public Map update(@RequestBody Integral integral);

    @RequestMapping("/{id}")
    public Map deleteById(@PathVariable("id") Integer id);

    @RequestMapping("/getOne")
    public Integral getOne(@RequestParam("id") Integer id);

    @RequestMapping("/getByCondition")
    public Integral getByCondition(@RequestParam("id") Integer id,@RequestParam("Type") String type);

    @RequestMapping("/getAll")
    public List<Integral> getAll();



}

接口调用

@RestController
@RequestMapping("/orders")
public class OrderController {
    @Autowired
    private IntegralApi integralApi;

//    

    @RequestMapping("/saveIntegral")
    public String saveIntegral() {
        Integral integral = new Integral();
        integral.setId(1);
        integral.setCount(9527);
        integral.setType("促销活动");
        Map save = integralApi.save(integral);
        System.out.println(save);
        return "ok";
    }

    @RequestMapping("/update")
    public String testUpdate() {

        Integral integral = new Integral();
        integral.setId(1);
        integral.setCount(9527);
        integral.setType("促销活动");
        Map save = integralApi.update(integral);
        System.out.println(save);
        return "ok";

    }

    @RequestMapping("/delete/{id}")
    public String testDelete(@PathVariable("id") Integer id){

        Map map = integralApi.deleteById(id);
        System.out.println(map);
        return "ok";
    }

    @RequestMapping("/getOne")
    public String getOne(Integer id){
        System.out.println(id);

        Integral one = integralApi.getOne(id);
        System.out.println(one);
        return "ok";
    }

    @RequestMapping("/getByCondition")
    public String getByCondition(Integer id, String type){

        Integral byCondition = integralApi.getByCondition(id, type);
        System.out.println(byCondition);
        return "ok";
    }

    @RequestMapping("/getAll")
    public String getAll(){
        List<Integral> all = integralApi.getAll();
        System.out.println(all);
        return "ok";
    }

}

实例访问