springboot中的jackson配置及Jackson工具类分享

目录

springboot中的Jackson配置

Jackson工具类

---

springboot中的Jackson配置

  spring:
    jackson:
      # 设置属性命名策略,对应jackson下PropertyNamingStrategy中的常量值，SNAKE_CASE-返回的json驼峰式转下划线，json body下划线传到后端自动转驼峰式
      property-naming-strategy: SNAKE_CASE
      # 全局设置@JsonFormat的格式pattern
      date-format: yyyy-MM-dd HH:mm:ss
      # 当地时区
      locale: zh
      # 设置全局时区
      time-zone: GMT+8
      # 常用，全局设置pojo或被@JsonInclude注解的属性的序列化方式
      default-property-inclusion: NON_NULL #不为空的属性才会序列化,具体属性可看JsonInclude.Include
      # 常规默认,枚举类SerializationFeature中的枚举属性为key，值为boolean设置jackson序列化特性,具体key请看SerializationFeature源码
      serialization:
        WRITE_DATES_AS_TIMESTAMPS: true # 返回的java.util.date转换成timestamp
        FAIL_ON_EMPTY_BEANS: true # 对象为空时是否报错，默认true
      # 枚举类DeserializationFeature中的枚举属性为key，值为boolean设置jackson反序列化特性,具体key请看DeserializationFeature源码
      deserialization:
        # 常用,json中含pojo不存在属性时是否失败报错,默认true
        FAIL_ON_UNKNOWN_PROPERTIES: false
      # 枚举类MapperFeature中的枚举属性为key，值为boolean设置jackson ObjectMapper特性
      # ObjectMapper在jackson中负责json的读写、json与pojo的互转、json tree的互转,具体特性请看MapperFeature,常规默认即可
      mapper:
        # 使用getter取代setter探测属性，如类中含getName()但不包含name属性与setName()，传输的vo json格式模板中依旧含name属性
        USE_GETTERS_AS_SETTERS: true #默认false
      # 枚举类JsonParser.Feature枚举类中的枚举属性为key，值为boolean设置jackson JsonParser特性
      # JsonParser在jackson中负责json内容的读取,具体特性请看JsonParser.Feature，一般无需设置默认即可
      parser:
        ALLOW_SINGLE_QUOTES: true # 是否允许出现单引号,默认false
      # 枚举类JsonGenerator.Feature枚举类中的枚举属性为key，值为boolean设置jackson JsonGenerator特性，一般无需设置默认即可
      # JsonGenerator在jackson中负责编写json内容,具体特性请看JsonGenerator.Feature

Jackson工具类

import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * Jackson 工具类
 * 
Title: MapperUtils
 * 
Description: 
 *
 */
public class MapperUtils {
    private final static ObjectMapper objectMapper = new ObjectMapper();

    public static ObjectMapper getInstance() {
        return objectMapper;
    }

    /**
     * 转换为 JSON 字符串
     *
     * @param obj
     * @return
     * @throws Exception
     */
    public static String obj2json(Object obj) throws Exception {
        ObjectMapper mapper = new ObjectMapper();
        mapper.setSerializationInclusion(JsonInclude.Include.ALWAYS);
        return mapper.writeValueAsString(obj);
    }

    /**
     * 转换为 JSON 字符串，忽略空值
     *
     * @param obj
     * @return
     * @throws Exception
     */
    public static String obj2jsonIgnoreNull(Object obj) throws Exception {
        ObjectMapper mapper = new ObjectMapper();
        mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
        return mapper.writeValueAsString(obj);
    }

    /**
     * 转换为 JavaBean
     *
     * @param jsonString
     * @param clazz
     * @return
     * @throws Exception
     */
    public static  T json2pojo(String jsonString, Class clazz) throws Exception {
        objectMapper.configure(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY, true);
        return objectMapper.readValue(jsonString, clazz);
    }

    /**
     * 字符串转换为 Map
     *
     * @param jsonString
     * @return
     * @throws Exception
     */
    public static  Map json2map(String jsonString) throws Exception {
        ObjectMapper mapper = new ObjectMapper();
        mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
        return mapper.readValue(jsonString, Map.class);
    }

    /**
     * 字符串转换为 Map
     */
    public static  Map json2map(String jsonString, Class clazz) throws Exception {
        Map> map = objectMapper.readValue(jsonString, new TypeReference>() {
        });
        Map result = new HashMap();
        for (Map.Entry> entry : map.entrySet()) {
            result.put(entry.getKey(), map2pojo(entry.getValue(), clazz));
        }
        return result;
    }

    /**
     * 深度转换 JSON 成 Map
     *
     * @param json
     * @return
     */
    public static Map json2mapDeeply(String json) throws Exception {
        return json2MapRecursion(json, objectMapper);
    }

    /**
     * 把 JSON 解析成 List，如果 List 内部的元素存在 jsonString，继续解析
     *
     * @param json
     * @param mapper 解析工具
     * @return
     * @throws Exception
     */
    private static List