Spring MVC项目使用Feign声明式服务调用

<!-- https://mvnrepository.com/artifact/io.github.openfeign/feign-core -->
<dependency>
    <groupId>io.github.openfeign</groupId>
    <artifactId>feign-core</artifactId>
    <version>10.2.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/io.github.openfeign/feign-gson -->
<dependency>
    <groupId>io.github.openfeign</groupId>
    <artifactId>feign-gson</artifactId>
    <version>10.2.0</version>
</dependency>

请求（查找全部师范大学）：
http://api.yesapi.cn/?s=App.Common_University.Search&school_name=师范&app_key={你的app_key}&sign={动态签名}

返回：
{
    "ret": 200,
    "data": {
        "err_code": 0,
        "err_msg": "",
        "schools": [
            {
                "school_name": "北京师范大学",
                "school_province": "北京",
                "school_level": "本科",
                "school_website": "http://www.bnu.edu.cn/",
                "school_city": "北京市"
            }...
        ]
    },
    "msg": "当前请求接口：App.Common_University.Search"
}

@Data
public class YesResponse<T> {
    private Integer ret;
    private String msg;
    private T data;
}

@Data
public class YesUniversity {
    private String err_code;
    private String err_msg;
    private List<School> schools;
}

@Data
public class School {
    private String school_name;
    private String school_province;
    private String school_level;
    private String school_website;
    private String school_city;
}

@Data
public class YesVo {
    private String school_name;
    private String app_key;
    private String sign;
}

public interface Yes {
    @RequestLine("POST /?s=App.Common_University.Search")
    YesResponse<YesUniversity> appCommonUniversitySearch(@QueryMap YesVo vo);
}

public class YesService {
    public YesResponse<YesUniversity> appCommonUniversitySearch(){
        Yes yes=Feign.builder().decoder(new GsonDecoder()).target(Yes.class,"http://api.yesapi.cn");
        YesVo yesVo=new YesVo();
        yesVo.setSchool_name("师范");
        yesVo.setApp_key("你的app_key");
        yesVo.setSign("你的sign");
        return yes.appCommonUniversitySearch(yesVo);
    }

    public static void main(String[] args) {
        YesService yesService = new YesService();
        YesResponse<YesUniversity> yesUniversityYesResponse = yesService.appCommonUniversitySearch();
        System.out.println(JSON.toJSONString(yesUniversityYesResponse));
    }
}

@RequestLine("GET ?service={service}&app_key={appKey}&sign={sign}")Result<JokeInfo<String>> res(@Param("service") String service,@Param("appKey") String appKey, @Param("sign") String sign);

**如上的GET请求的写法,也是可以支持的.**

### 3.更多的用法

使用Feign还有更多的用法,可以参考其官方的用法,[传送门](https://github.com/OpenFeign/feign)