Java 利用枚举封装接口返回 JSON 结构

利用枚举封装返回码和返回信息

package com.template.project.util;

public enum StatusCode {

    SUCCESS(20000, "成功"), FAIL(50000, "失败"),

    REQUEST_PARAM_ERROR(50001, "请求参数错误");

    private int code;

    private String message;

    StatusCode(int code, String message) {
        this.code = code;
        this.message = message;
    }

    public int getCode() {
        return code;
    }

    public void setCode(int code) {
        this.code = code;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

}

封装返回类型，可按需要增加相应的构造方法

package com.template.project.util;

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

import com.alibaba.fastjson.JSONObject;

public class ResultBuilder<T> {

    public ResultBuilder(T data, int code, String message) {
        this.result = data;
        this.code = code;
        this.message = message;
        this.responseTime = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
    }

    public ResultBuilder(T data, StatusCode statusCode) {
        this.result = data;
        this.code = statusCode.getCode();
        this.message = statusCode.getMessage();
        this.responseTime = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
    }

    public ResultBuilder(T data, StatusCode statusCode, String extendMsg) {
        this.result = data;
        this.code = statusCode.getCode();
        this.message = statusCode.getMessage() + extendMsg;
        this.responseTime = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
    }

    public ResultBuilder(StatusCode statusCode) {
        this.code = statusCode.getCode();
        this.message = statusCode.getMessage();
        this.responseTime = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
    }

    public ResultBuilder(StatusCode statusCode, String extendMsg) {
        this.code = statusCode.getCode();
        this.message = statusCode.getMessage() + extendMsg;
        this.responseTime = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
    }

    public ResultBuilder(int code, String message) {
        this.code = code;
        this.message = message;
        this.responseTime = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
    }

    public ResultBuilder(int code) {
        this.code = code;
        this.responseTime = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
    }

    private int code;

    private String message;

    private T result;

    private String responseTime;

    public int getCode() {
        return code;
    }

    public void setCode(int code) {
        this.code = code;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public T getResult() {
        return this.result;
    }

    public void setResult(T result) {
        this.result = result;
    }

    public String getResponseTime() {
        return responseTime;
    }

    public void setResponseTime(String responseTime) {
        this.responseTime = responseTime;
    }

    public JSONObject toJSONObject() {
        JSONObject out = new JSONObject();
        out.put("code", code);
        out.put("message", message);
        out.put("result", result);
        out.put("responseTime", responseTime);
        return out;
    }

    @Override
    public String toString() {
        return toJSONObject().toString();
    }
    
}

接下来看看测试结果

public class Test {
    
    public static void main(String[] args) {
        JSONObject jobj = new JSONObject();
        jobj.put("name", "wangbo");
        jobj.put("age", 29);
        ResultBuilder<JSONObject> resultBuilder = new ResultBuilder<>(jobj, StatusCode.SUCCESS);
        System.out.println(resultBuilder);
    }

}

执行结果为

{"result":{"name":"wangbo","age":29},"code":20000,"responseTime":"2018-09-04 11:00:09","message":"成功"}

统一响应格式有助于系统间调用和前端解析。