在项目开发中，我们通常需要一个统一的结果返回类，返回一般主要由三个内容：

• code：业务处理结果编码

• msg：业务处理结果说明

• data：业务处理响应数据（具体由每个接口定义）

项目源码：common-result_R

创建项目

创建一个 Spring Boot 项目，你有两种方式选择：

• 1、根据提供的 pom.xml 文件自己创建

• 2、点击下载创建好的项目：common-result_O

项目中使用了lombok来简化代码

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.3</version>
        <relativePath/>
    </parent>
    <groupId>com.marui.common.result</groupId>
    <artifactId>common-result</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>8</java.version>
    </properties>
    <dependencies>
        <!-- Web开发场景所需的所有依赖 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- 简化代码 -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.22</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

通用结果类

成功编码默认为000000，错误编码默认为500，可根据自己具体情况定义。

package com.marui.common.result.common;

import lombok.Data;

import java.io.Serializable;

/**
 * @ClassName ResultDTO
 * @Desciption
 * @Author MaRui
 * @address https://maruinotes.com
 * @Date 2022/2/10 9:46
 * @Version 1.0
 */
@Data
public class ResultDTO<T> implements Serializable {

    /**
     * 业务处理结果编码
     */
    private String code;

    /**
     * 业务处理结果信息
     */
    private String msg;

    /**
     * 业务处理响应数据
     */
    private T data;

    public ResultDTO() {
    }

    public ResultDTO(String code) {
        this.code = code;
    }

    public ResultDTO(String code, String msg) {
        this.code = code;
        this.msg = msg;
    }

    public ResultDTO(String code, String msg, T data) {
        this.code = code;
        this.msg = msg;
        this.data = data;
    }

    public static <T> ResultDTO<T> ok() {
        return new ResultDTO("000000", "Success");
    }

    public static <T> ResultDTO<T> ok(T data) {
        return new ResultDTO("000000", "Success", data);
    }

    public static <T> ResultDTO<T> ok(String code, String msg, T data) {
        return new ResultDTO(code, msg, data);
    }

    public static <T> ResultDTO<T> error() {
        return new ResultDTO("500", "未知异常，请联系管理员");
    }

    public static <T> ResultDTO<T> error(String msg) {
        return new ResultDTO("500", msg);
    }

    public static <T> ResultDTO<T> error(String code, String msg) {
        return new ResultDTO(code, msg);
    }
}

测试

package com.marui.common.result.controller;

import com.marui.common.result.common.ResultDTO;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

/**
 * @ClassName UserController
 * @Desciption
 * @Author MaRui
 * @address https://maruinotes.com
 * @Date 2022/2/10 9:55
 * @Version 1.0
 */
@RestController
@RequestMapping(value = "/user")
public class UserController {

    @GetMapping(value = "/sayHello")
    public ResultDTO<String> sayHello(@RequestParam String name) {
        return ResultDTO.ok("你好，" + name);
    }
}