SpringBoot处理JSON数据

逃离我推掉我的手 2023-10-17 22:21 116阅读 0赞

SpringBoot内置了JSON解析功能，默认使用Jackson来自动完成

当Controller返回的是一个Java对象或者是List集合时，SpringBoot自动将其转换成JSON数据

一、新建项目

1.创建一个Maven项目，命名为SpringBoot\_jsontest,按照Maven项目的规范，src/main下新建一个resources的文件夹，再在此文件夹下新建static以及template两个文件夹。

2.修改pom.xml文件

<groupId>org.fkit</groupId>  
<artifactId>jsontest</artifactId>  
<version>0.0.1-SNAPSHOT</version>  
<packaging>jar</packaging>

<name>jsontest</name>  
<url>http://maven.apache.org</url>

<parent>  
<groupId>org.springframework.boot</groupId>  
<artifactId>spring-boot-starter-parent</artifactId>  
<version>2.0.0.RELEASE</version>  
<relativePath/>  
</parent>  
  
<properties>  
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>  
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>  
<java.version>1.8</java.version>  
</properties>

<dependencies>  
  
  
<dependency>  
<groupId>org.springframework.boot</groupId>  
<artifactId>spring-boot-starter-web</artifactId>  
</dependency>  
  
  
<dependency>  
<groupId>org.springframework.boot</groupId>  
<artifactId>spring-boot-starter-thymeleaf</artifactId>  
</dependency>  
  
<dependency>  
<groupId>junit</groupId>  
<artifactId>junit</artifactId>  
<scope>test</scope>  
</dependency>  
</dependencies>  
</project>

3.引入静态文件

![70][]![Image 1][]

二、创建实体类

Dog.java:

package com.ysh.jsontest.domain;

import java.io.Serializable;

public class Dog implements Serializable \{  
private Integer id;  
private String name;  
private String image;  
private Double price;  
private String owner;  
  
public Dog() \{  
  
// TODO Auto-generated constructor stub  
\}  
public Dog(Integer id, String name, String image, Double price, String owner) \{  
  
this.id = id;  
this.name = name;  
this.image = image;  
this.price = price;  
this.owner = owner;  
\}  
public Integer getId() \{  
return id;  
\}  
public void setId(Integer id) \{  
this.id = id;  
\}  
public String getName() \{  
return name;  
\}  
public void setName(String name) \{  
this.name = name;  
\}  
public String getImage() \{  
return image;  
\}  
public void setImage(String image) \{  
this.image = image;  
\}  
public Double getPrice() \{  
return price;  
\}  
public void setPrice(Double price) \{  
this.price = price;  
\}  
public String getOwner() \{  
return owner;  
\}  
public void setOwner(String owner) \{  
this.owner = owner;  
\}

三、创建index.html

<!DOCTYPE html>  
<html xmlns:th="[http://www.thymeleaf.org][http_www.thymeleaf.org]">  
<head>  
<meta charset="UTF-8"></meta>  
<title>Spring Boot自动转换JSON数据</title>  
<link rel="stylesheet" th:href="@\{css/bootstrap.min.css\}" />  
<link rel="stylesheet" th:href="@\{css/bootstrap-theme.min.css\}"/>  
<script type="text/javascript" th:src="@\{js/jquery-1.11.0.min.js\}"></script>  
<script type="text/javascript" th:src="@\{js/bootstrap.min.js\}"></script>  
<script type="text/javascript">  
$(document).ready(function()\{  
findDog();  
\});  
function findDog()\{  
$.ajax("/findDog",// 发送请求的URL字符串。  
\{  
dataType : "json", // 预期服务器返回的数据类型。  
type : "post", // 请求方式 POST或GET  
contentType:"application/json", // 发送信息至服务器时的内容编码类型  
// 发送到服务器的数据。该函数的作用是：系列化对象 ,系列化对象说白了就是把对象的类型转换为字符串类型  
data:JSON.stringify(\{id : 1, name : "巴扎黑"\}),  
async: true , // 默认设置下，所有请求均为异步请求。如果设置为false，则发送同步请求  
// 请求成功后的回调函数。  
success :function(data)\{  
console.log(data);  
$("\#image").attr("src","images/"+data.image+"");  
$("\#name").html(data.name);  
$("\#price").html(data.price);  
$("\#owner").html(data.owner);  
\},  
// 请求出错时调用的函数  
error:function()\{  
alert("数据发送失败");  
\}  
\});  
\}  
</script>  
</head>  
<body>  
<div class="panel panel-primary">  
<div class="panel-heading">  
<h3 class="panel-title">Spring Boot中Java对象转换JSON</h3>  
</div>  
</div>  
<div class="container">  
<div class="row">  
<div class="col-md-4">  
<p>照片：<img id="image" src="images/1.jpg" width="60" height="60"/></p>  
<p>名字：<span id="name"></span></p>  
<p>价格：<span id="price"></span></p>  
<p>主人：<span id="owner"></span></p>  
</div>  
</div>  
</div>  
</body>  
</html>

四、创建AppController控制器

package com.ysh.jsontest.controller;

import org.springframework.stereotype.Controller;  
import org.springframework.web.bind.annotation.RequestMapping;

@Controller  
public class AppController \{

@RequestMapping(value = "/index")  
public String index() \{  
return "index";  
\}  
  
@RequestMapping(value = "/getjson")  
public String getjson() \{  
return "getjson";  
\}

五、创建DogController控制器

package com.ysh.jsontest.controller;

import java.util.ArrayList;  
import java.util.List;  
import org.springframework.web.bind.annotation.RequestBody;  
import org.springframework.web.bind.annotation.RequestMapping;  
import org.springframework.web.bind.annotation.RestController;  
import com.ysh.jsontest.domain.Dog;  
@RestController  
public class DogController \{  
  
/\*\*  
\* Spring Boot默认使用jackson框架解析jason  
\* \*/  
@RequestMapping("/findDog")  
public Dog findDog(@RequestBody Dog dog)\{  
// 观察页面传入的json数据是否封装到Dog对象  
System.out.println(dog);  
// 设置dog其他信息  
dog.setImage("2.jpg");  
dog.setPrice(58.0);  
dog.setOwner("badao");  
return dog;  
\}

附：

findDog中的参数@RequestBody Dog dog 表示，使用@RequestBody注解获取页面传递的参数后，将JSON数据设置到对应的Book的属性中。

六、启动测试项目

项目启动后，在浏览器输入：[http://localhost:8080/index][http_localhost_8080_index]

请求会提交到AppController类的index方法进行处理，传递JSON数据，该方法返回index字符串，即转到template/index.html中

![70 1][]![Image 1][]

七、启动测试SpringBoot转换集合数据

getjson.html:

<!DOCTYPE html>  
<html xmlns:th="[http://www.thymeleaf.org][http_www.thymeleaf.org]">  
<head>  
<meta charset="UTF-8"></meta>  
<title>Spring Boot Web开发测试</title>  
<link rel="stylesheet" th:href="@\{css/bootstrap.min.css\}" />  
<link rel="stylesheet" th:href="@\{css/bootstrap-theme.min.css\}"/>  
<script type="text/javascript" th:src="@\{js/jquery-1.11.0.min.js\}"></script>  
<script type="text/javascript" th:src="@\{js/bootstrap.min.js\}"></script>  
<script type="text/javascript">  
$(document).ready(function()\{  
findDogs();  
\});  
function findDogs()\{  
$.post("/finddogs",null,  
function(data)\{  
$.each(data,function()\{  
var tr = $("<tr/>");  
$("<img/>").attr("src","images/"+this.image).attr("height",60).attr("width",60).appendTo("<td/>").appendTo(tr);  
$("<td/>").html(this.name).appendTo(tr);  
$("<td/>").html(this.price).appendTo(tr);  
$("\#dogtable").append(tr);  
\})  
\},"json");  
\}  
</script>  
</head>  
<body>  
<div class="panel panel-primary">  
<div class="panel-heading">  
<h3 class="panel-title">Spring Boot中集合转换JSON</h3>  
</div>  
</div>  
  
<div class="container">  
<div class="col-md-12">  
<div class="panel panel-primary">  
  
<div class="panel-heading">  
  
<h3 class="panel-title">图书信息列表</h3>  
</div>  
<div class="panel-body">  
  
<div class="table table-responsive">  
  
<table class="table table-bordered table-hover" id="dogtable">  
<thead>  
<tr>  
<th class="text-center">照片</th >  
<th class="text-center">名字</th>  
<th class="text-center">价格</th >  
</tr>  
</thead>  
<tbody class="text-center"></tbody>  
</table>  
</div>  
</div>  
</div>  
</div>  
</div>  
</body>  
</html>

附：

## jQuery中选择器加尖括号的区别: ##

$("<img/>")：

[https://blog.csdn.net/badao\_liumang\_qizhi/article/details/80987336][https_blog.csdn.net_badao_liumang_qizhi_article_details_80987336]

getjson.html页面使用jQuery发送请求，页面载入时调用findDogs函数，它会发送异步请求到“/finddogs”,请求成功后会返回一个JSON数据，包含多个狗狗信息，接着将返回的数据使用jQuery设置到页面的table表单当中。

八、向DogController控制器中加入代码

@RequestMapping("/finddogs")  
public List<Dog> findBooks()\{  
// 创建集合  
List<Dog> dogs = new ArrayList<Dog>();  
// 添加狗对象  
dogs.add(new Dog(1, "巴扎黑1", "1.jpg",109.00,"ysh"));  
dogs.add(new Dog(2, "巴扎黑2", "2.jpg",108.00,"badao"));  
dogs.add(new Dog(3, "巴扎黑3", "3.jpg",58.00,"liumang"));  
dogs.add(new Dog(4, "巴扎黑4", "4.jpg",108.00,"qi"));  
dogs.add(new Dog(5, "巴扎黑5", "5.jpg",79.00,"zhi"));  
// 返回集合  
return dogs;  
\}

springboot会将List数据转换成JSON格式后返回到客户端

九、测试返回的集合转换成JSON

运行APP:参照

[https://blog.csdn.net/badao\_liumang\_qizhi/article/details/80948956][https_blog.csdn.net_badao_liumang_qizhi_article_details_80948956]

访问：[http://localhost:8080/getjson][http_localhost_8080_getjson]

请求响应如图：

![70 2][]

![Image 1][]

代码下载：

[https://download.csdn.net/download/badao\_liumang\_qizhi/10533476][https_download.csdn.net_download_badao_liumang_qizhi_10533476]

[http_maven.apache.org_POM_4.0.0]: http://maven.apache.org/POM/4.0.0
[http_www.w3.org_2001_XMLSchema-instance]: http://www.w3.org/2001/XMLSchema-instance
[http_maven.apache.org_xsd_maven-4.0.0.xsd]: http://maven.apache.org/xsd/maven-4.0.0.xsd
[70]: https://img-blog.csdn.net/20180711072545388?watermark/2/text/aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70
[Image 1]: 
[http_www.thymeleaf.org]: http://www.thymeleaf.org/
[http_localhost_8080_index]: http://localhost:8080/index
[70 1]: https://img-blog.csdn.net/20180711072709575?watermark/2/text/aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70
[https_blog.csdn.net_badao_liumang_qizhi_article_details_80987336]: https://blog.csdn.net/badao_liumang_qizhi/article/details/80987336
[https_blog.csdn.net_badao_liumang_qizhi_article_details_80948956]: https://blog.csdn.net/badao_liumang_qizhi/article/details/80948956
[http_localhost_8080_getjson]: http://localhost:8080/getjson
[70 2]: https://img-blog.csdn.net/20180711072747624?watermark/2/text/aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70
[https_download.csdn.net_download_badao_liumang_qizhi_10533476]: https://download.csdn.net/download/badao_liumang_qizhi/10533476