JavaWeb實體類轉(zhuǎn)為json對象的實現(xiàn)方法

更新時間：2020年12月20日 08:39:14 作者：牛哄哄的柯南

這篇文章主要介紹了JavaWeb實體類轉(zhuǎn)為json對象的實現(xiàn)方法，文中通過示例代碼介紹的非常詳細，對大家的學習或者工作具有一定的參考學習價值，需要的朋友們下面隨著小編來一起學習學習吧

1.創(chuàng)建個實體類

實體類User代碼：

package com.neuedu.entity;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.util.Date;

/**
 * Keafmd
 *
 * @ClassName: User
 * @Description: user實體類
 * @author: 牛哄哄的柯南
 * @date: 2020-12-17 14:08
 */

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {

  private Integer id;
  private String name;
  private String address;
  private Date date;

}

我沒有自己寫構(gòu)造函數(shù)和Setter()，Getter()以及toString()方法，而是使用了lombok自動生成的。

2.使用類庫 fastjson

添加依賴：

<dependency>
   <groupId>com.alibaba</groupId>
   <artifactId>fastjson</artifactId>
   <version>1.2.73</version>
</dependency>

3.測試一下

JsonTest 代碼：

package com.neuedu.entity;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializerFeature;
import org.junit.Test;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**
 * Keafmd
 *
 * @ClassName: Test
 * @Description: user測試類
 * @author: 牛哄哄的柯南
 * @date: 2020-12-17 14:10
 */

public class JsonTest {

  @Test
  public void test(){
    List userList = new ArrayList();
    userList.add(new User(1,"牛哄哄的柯南1","某某省某某市1",new Date()));
    userList.add(new User(2,"牛哄哄的柯南2","某某省某某市2",new Date()));
    userList.add(new User(3,"牛哄哄的柯南3","某某省某某市3",new Date()));
    userList.add(new User(4,"牛哄哄的柯南4","某某省某某市4",new Date()));
    userList.add(new User(5,"牛哄哄的柯南5","某某省某某市5",new Date()));
    userList.add(new User(6,"牛哄哄的柯南6","某某省某某市6",new Date()));


    //List集合轉(zhuǎn)換成 json


    String json = JSON.toJSONString(userList,  SerializerFeature.WriteDateUseDateFormat );


    System.out.println(json);

  }
}

運行結(jié)果：

[{"address":"某某省某某市1","date":"2020-12-17 21:09:21","id":1,"name":"牛哄哄的柯南1"},
{"address":"某某省某某市2","date":"2020-12-17 21:09:21","id":2,"name":"牛哄哄的柯南2"},
{"address":"某某省某某市3","date":"2020-12-17 21:09:21","id":3,"name":"牛哄哄的柯南3"},
{"address":"某某省某某市4","date":"2020-12-17 21:09:21","id":4,"name":"牛哄哄的柯南4"},
{"address":"某某省某某市5","date":"2020-12-17 21:09:21","id":5,"name":"牛哄哄的柯南5"},
{"address":"某某省某某市6","date":"2020-12-17 21:09:21","id":6,"name":"牛哄哄的柯南6"}]

Process finished with exit code 0

4.Controller代碼

UserController代碼：

package com.neuedu.controller;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.neuedu.entity.User;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
/**
 * Keafmd
 *
 * @ClassName: UserController
 * @Description: UserController
 * @author: 牛哄哄的柯南
 * @date: 2020-12-17 14:20
 *
 *
 * http://127.0.0.1:8080/web/user
 */

@WebServlet(name="UserController" ,urlPatterns = "/user")
public class UserController extends HttpServlet {

  @Override
  protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

    List userList = new ArrayList();
    userList.add(new User(1,"牛哄哄的柯南1","某某省某某市1",new Date()));
    userList.add(new User(2,"牛哄哄的柯南2","某某省某某市2",new Date()));
    userList.add(new User(3,"牛哄哄的柯南3","某某省某某市3",new Date()));
    userList.add(new User(4,"牛哄哄的柯南4","某某省某某市4",new Date()));
    userList.add(new User(5,"牛哄哄的柯南5","某某省某某市5",new Date()));
    userList.add(new User(6,"牛哄哄的柯南6","某某省某某市6",new Date()));

    String json = JSON.toJSONString(userList,  SerializerFeature.WriteDateUseDateFormat  );


    resp.setContentType("application/json");
    resp.setCharacterEncoding("utf-8");
    PrintWriter out = resp.getWriter();
    out.write(json);
    out.flush();
    out.close();

  }

  @Override
  protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    this.doGet(req, resp);
  }
}

啟動服務(wù)訪問http://127.0.0.1:8080/web/user

訪問結(jié)果：