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：
4.0.0 com.qinker spring-bootwar org.springframework.boot spring-boot-starter-parent2.0.0.RELEASE 0.0.1-SNAPSHOT spring-boot http://maven.apache.org UTF-8 9 org.springframework.boot spring-boot-starter-webspring-boot
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";
}
@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：
com.alibaba fastjson1.2.47
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> 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 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 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考高分网。
