Spring Boot转化为json数据格式

野性酷女 2022-05-21 09:36 513阅读 0赞

Spring Boot为我们良好的提供了我们需要的数据,将数据转化为json格式,然后返回,

下面请看springboot转化为json的方式;

**第一种方式:**

**SpringBoot框架默认的方式;**

步骤:

**\* 1.编写实体类student;**

package com.gmm; 
    /**测试的实体类 * Created by john on 2017-04-30. */ public class Student {
       
        private Integer sId; private String sName; private String gender; 
     public Integer getsId() {
       
            return sId; }
    
        public void setsId(Integer sId) {
       
            this.sId = sId; }
    
        public String getsName() {
       
            return sName; }
    
        public void setsName(String sName) {
       
            this.sName = sName; }
    
        public String getGender() {
       
            return gender; }
    
        public void setGender(String gender) {
       
            this.gender = gender; }
    }

**\* 2.编写getStudernt()方法在controller中;**

**写法:创建一个学生对象设置学生属性信息数据然后获取以json的方式获取这些数据;**

package com.gmm; 
    import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; 
    /** * Created by john on 2017-04-30. */ @RestController
    public class Controller {
       
    
    
        /** * springboot默认使用的json解析框架是jackson; * @return */ @RequestMapping("/getStudent")
        public Student getStudent(){
       
            Student student = new Student(); student.setGender("女"); student.setsName("莉香"); student.setsId(1); return student; }
    }

注意:

@RestController 此注解是代表当前类是一个Restful API的controller;

@RequestMapping("/getStudent") 此注解是请求的映射路径;

**\* 3.进行测试;**

**编写一个Springboot的入口程序;**

package com.gmm; 
    import org.apache.log4j.Logger; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; 
    /** * Created by john on 2017-04-30. */ @SpringBootApplication
    public class Application {
       
    
        private static Logger logger = Logger.getLogger(Application.class); 
    
     public static void main(String[] args) {
       
            SpringApplication.run(Application.class,args); logger.info("=====spring boot start success===="); }
    }

注:访问路径为http://localhost:8080/getStudent

**谷歌游览器页面显示的结果为:**

{"sId":1,"sName":"莉香","gender":"女"}

以上我们了解到SpringBootmoren 默认使用的json解析技术框架是jackson;

在maven下载的架包中可以看到有一个jackson.jar架包;

以上是第一种解析方式,通常我们也是用其它的解析方式;

第二种方式;

Spring Boot使用FastJson解析JSON数据

步骤

**\* 1.在上面pom,xml文件依赖的基础上添加FastJson的依赖包;**

**完整pom文件**

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> 
     <groupId>springbootjson</groupId> <artifactId>com.gmm</artifactId> <version>1.0-SNAPSHOT</version> 
     <parent>
     <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.4.1.RELEASE</version> </parent> 
     <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>  <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-configuration-processor</artifactId> <optional>true</optional> <scope>test</scope> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.15</version> </dependency> 
     </dependencies>
    </project>

在这个地方我们要强调一下，在官方文档说的1.2.10以后，会有两个方法支持HttpMessageconvert，一个是FastJsonHttpMessageConverter，支持4.2以下的版本，一个是FastJsonHttpMessageConverter4支持4.2以上的版本，这里也就是说：低版本的就不支持了，所以这里最低要求就是1.2.10+。具体看文档!

**\* 2.配置fastjon(支持两种方法);**

**第一种方法:**

**一:启动类继承extends WebMvcConfigurerAdapter**

**二:覆盖方法configureMessageConverters**

package com.gmm; 
    import com.alibaba.fastjson.serializer.SerializerFeature; import com.alibaba.fastjson.support.config.FastJsonConfig; import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter; import org.apache.log4j.Logger; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.autoconfigure.web.HttpMessageConverters; import org.springframework.context.annotation.Bean; import org.springframework.http.MediaType; import org.springframework.http.converter.HttpMessageConverter; import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter; 
    import java.util.ArrayList; import java.util.List; 
    /** springboot以fastjon方式转化json数据; * Created by john on 2017-04-30. */ @SpringBootApplication public class Application extends WebMvcConfigurerAdapter {
       
        private static Logger logger = Logger.getLogger(Application.class); 
     @Override public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
       
            super.configureMessageConverters(converters); //1.需要定义一个convert转换消息的对象; FastJsonHttpMessageConverter fastJsonHttpMessageConverter = new FastJsonHttpMessageConverter(); //2.添加fastJson的配置信息，比如：是否要格式化返回的json数据; FastJsonConfig fastJsonConfig = new FastJsonConfig(); fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat); //3处理中文乱码问题 List<MediaType> fastMediaTypes = new ArrayList<>(); fastMediaTypes.add(MediaType.APPLICATION_JSON_UTF8); //4.在convert中添加配置信息. fastJsonHttpMessageConverter.setSupportedMediaTypes(fastMediaTypes); fastJsonHttpMessageConverter.setFastJsonConfig(fastJsonConfig); //5.将convert添加到converters当中. converters.add(fastJsonHttpMessageConverter); }
     public static void main(String[] args) {
       
            SpringApplication.run(Application.class,args); logger.info("=====spring boot start success===="); }
    }

三:在启动测试实体类中添加一个属性;并提供getset方法;

@JSONField(format = "yyyy-MM-dd HH:mm")
    private Date createTime; 
    public Date getCreateTime() {
       
        return createTime; }
    
    public void setCreateTime(Date createTime) {
       
        this.createTime = createTime; }

@JSONField(format = "yyyy-MM-dd HH:mm")此注解是fastjon包提供的用于指定将数据返回什么样的json格式数据;

四:在controller中在将添加的实体属性给加进去;

@RequestMapping("/getStudent") public Student getStudent(){ Student student = new Student(); student.setGender("女"); student.setsName("莉香"); student.setsId(1); student.setCreateTime(new Date());
     return student; }

五:开启springboot测试结果;

**结果为:**

**![Center][]**

**说明springboot按照fastjson的方式将数据以json格式解析出来了;**

**第二种方法:**

**一:启动测试类中注入Bean: HttpMessageConverters**

**具体做法:删除继承extends WebMvcConfigurerAdapter;**

**      删除重写的方法改为以下代码;**

@Bean
    public HttpMessageConverters fastJsonHttpMessageConverters(){
       
        //1.需要定义一个convert转换消息的对象; FastJsonHttpMessageConverter fastJsonHttpMessageConverter = new FastJsonHttpMessageConverter(); //2:添加fastJson的配置信息; FastJsonConfig fastJsonConfig = new FastJsonConfig(); fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat); //3处理中文乱码问题 List<MediaType> fastMediaTypes = new ArrayList<>(); fastMediaTypes.add(MediaType.APPLICATION_JSON_UTF8); //4.在convert中添加配置信息. fastJsonHttpMessageConverter.setSupportedMediaTypes(fastMediaTypes); fastJsonHttpMessageConverter.setFastJsonConfig(fastJsonConfig); HttpMessageConverter<?> converter = fastJsonHttpMessageConverter; return new HttpMessageConverters(converter); 
    }

二:在入口springboot类中测试结果;

**![Center][]**

**结果显示和上面的结果是一样的所有两种方式都是有效的,具体使用哪种方法我感觉还是看你自己了!**

[Center]: /images/20220521/b2f065e6d084488a9b16071c59cf14e5.png