Spring-Boot是基于Spring框架的，它并不是对Spring框架的功能增强，而是对Spring的一种快速构建的方式。
Spring-boot应用程序提供了默认的json转换器，为Jackson。示例：
pom.xml中dependency配置：
<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/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.qinker</groupId> <artifactId>spring-boot</artifactId> <packaging>war</packaging> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.0.RELEASE</version> </parent> <version>0.0.1-SNAPSHOT</version> <name>spring-boot</name> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <java.version>9</java.version> </properties> <dependencies> <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-web --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> </dependencies> <build> <finalName>spring-boot</finalName> </build> </project>
创建三个类：MainApp.java和User.java以及HelloController.java：
package com.springboot; import java.util.Date; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; @RestController public class HelloController { @RequestMapping("/hello") public String hello() { return "hello,SpringBoot"; } /** * Spring boot 默认json解析框架是Jackson * @return */ @RequestMapping("/getUser") public User getUser() { User u = new User(); u.setName("张三"); u.setAge(33); u.setCreateTime(new Date()); return u; } } package com.springboot; import java.io.Serializable; import java.util.Date; public class User implements Serializable{ private String name; private int age; private Date createTime; public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public Date getCreateTime() { return createTime; } public void setCreateTime(Date createTime) { this.createTime = createTime; } } package com.springboot; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class MainApp{ public static void main(String[] args) { SpringApplication.run(MainApp.class, args); } } 启动MainApp：访问http://localhost:8080/getUser,结果如下：
{"name":"张三","age":33,"createTime":"2018-04-04T03:03:08.534+0000"} 可见：我们并未做任何配置，返回的却是json数据，可见Spring-Boot对json做了默认实现，使用的是内置Jackson转换器。
那么，下面看看如何使用自定义的json转换器，这里以fastjson为例：
首先，引入fastjson包，在pom中添加如下依赖：
<!-- https://mvnrepository.com/artifact/com.alibaba/fastjson --> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.47</version> </dependency>
为了方便看出效果：修改User类：
package com.springboot; import java.io.Serializable; import java.util.Date; import com.alibaba.fastjson.annotation.JSONField; @SuppressWarnings("serial") public class User implements Serializable{ private String name; private int age; @JSONField(format="yyyy-MM-dd HH:mm") private Date createTime; public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public Date getCreateTime() { return createTime; } public void setCreateTime(Date createTime) { this.createTime = createTime; } } 1.实现fastjson自定义json转换的第一种方式，Spring-Boot实现WebMvcConventer接口：
修改MainApp如下：
package com.springboot; import java.util.ArrayList; import java.util.List; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.http.MediaType; import org.springframework.http.converter.HttpMessageConverter; import org.springframework.web.servlet.config.annotation.WebMvcConfigurer; import com.alibaba.fastjson.serializer.SerializerFeature; import com.alibaba.fastjson.support.config.FastJsonConfig; import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter; @SpringBootApplication public class MainApp implements WebMvcConfigurer{ @Override public void configureMessageConverters(List<HttpMessageConverter<?>> converters) { WebMvcConfigurer.super.configureMessageConverters(converters); //创建fastjson转换器实例 FastJsonHttpMessageConverter converter = new FastJsonHttpMessageConverter(); //配置对象 FastJsonConfig config = new FastJsonConfig(); List<MediaType> mediaTypes = new ArrayList<>(); //中文编码 MediaType mediaType = MediaType.APPLICATION_JSON_UTF8; mediaTypes.add(mediaType); config.setSerializerFeatures(SerializerFeature.PrettyFormat); converter.setSupportedMediaTypes(mediaTypes); converter.setFastJsonConfig(config); converters.add(converter); } public static void main(String[] args) { SpringApplication.run(MainApp.class, args); } } 启动程序：访问上面的路径：浏览器会看到如下结果：
{ "age":33, "createTime":"2018-04-04 11:14", "name":"张三" } 2.使用@Bean注解注入fastjson转换器：修改MainApp如下：
package com.springboot; import java.util.ArrayList; import java.util.List; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.autoconfigure.http.HttpMessageConverters; import org.springframework.context.annotation.Bean; import org.springframework.http.MediaType; import com.alibaba.fastjson.serializer.SerializerFeature; import com.alibaba.fastjson.support.config.FastJsonConfig; import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter; @SpringBootApplication public class MainApp{ @Bean public HttpMessageConverters fastJsonHttpMessageConventers() { FastJsonHttpMessageConverter converter = new FastJsonHttpMessageConverter(); FastJsonConfig config = new FastJsonConfig(); config.setSerializerFeatures(SerializerFeature.PrettyFormat); List<MediaType> mediaTypes = new ArrayList<>(); mediaTypes.add(MediaType.APPLICATION_JSON_UTF8); converter.setSupportedMediaTypes(mediaTypes); return new HttpMessageConverters(converter); } public static void main(String[] args) { SpringApplication.run(MainApp.class, args); } } 访问结果是一样的。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持武林网。