使用jackson实现对象json之间的相互转换(spring|使用jackson实现对象json之间的相互转换(spring boot) 使用jackson实现对象json之间的相

首先，在pom.xml里弄好依赖
用来获取天气预报接口的数据
返回的json字符串就像下面这个样子
我拆成了下面两个对象
开始书写工具类，方便以后调用~
封装完成，写测试类

之前的json转对象，对象转json。总是比较繁琐，不够简洁。自从接触到jackson之后，发现原来对象和json转换可以这么简单。拿一个天气预报的小例子来说明一下~如下图。【若是有小误，还望指正】
【使用jackson实现对象json之间的相互转换(spring|使用jackson实现对象json之间的相互转换(spring boot)】

使用jackson实现对象json之间的相互转换(spring|使用jackson实现对象json之间的相互转换(spring boot)

文章图片

不说，直接上码~

首先，在pom.xml里弄好依赖具体依赖需要上网去查找，咱用的是下面这个。

com.fasterxml.jackson.corejackson-databind2.7.4

然后嘞，准备一个接口，

用来获取天气预报接口的数据

package com.lvfeng.tool.weather; import java.io.ByteArrayOutputStream; import java.io.InputStream; import java.net.URL; /** * @author LvFeng * 来源：https://www.nowapi.com/ * 文档：https://www.nowapi.com/api/weather.future * 接口服务器【请求头】：https://sapi.k780.comhttp://api.k780.com * 每三个月一更新，需要定期更新 */public class WeatherAPI { /** 00a.天气预报接口*/ public static final String APP_KEY_WEATHER = "你自己的key"; //KEY public static final String SIGN_WEATHER = "你自己的sign"; //SIGN /** 001.获取一周的天气* @param 请求城市气象编码，请求APPKey，SignKey，返回数据格式* @return JSON* DOC:https://www.nowapi.com/api/weather.future* FORMAT:http://api.k780.com/?app=weather.future&weaid=1&appkey=APPKEY&sign=SIGN&format=json*/ public static String getWeatherWeek(String cityNumber,String ak,String sg,String returnFormat) throws Exception{String str = "http://api.k780.com/?app=weather.future&weaid="+cityNumber+"&appkey="+ak+"&sign="+sg+"&format="+returnFormat; URL url = new URL(str); //请求URLInputStream ins = url.openStream(); //打开输入流ByteArrayOutputStream out=new ByteArrayOutputStream(); try {byte buf[] = new byte[1024]; int read = 0; while ((read = ins.read(buf)) > 0) {out.write(buf, 0, read); }} finally {if (ins != null) {ins.close(); }}byte b[] = out.toByteArray( ); return new String(b,"utf-8"); //转码 }}

插一嘴，简单粗暴的讲，[]就是数组，{}就是对象，我们测试接口过后，

返回的json字符串就像下面这个样子

/* {* "success":"1",* "result":[{*"weaid":"1",*"days":"2018-07-18",*"week":"星期三",*"cityno":"beijing",*"citynm":"北京",*"cityid":"101010100",*"temperature":"32℃/25℃",*"humidity":"0%/0%",*"weather":"多云转小雨",*"weather_icon":"http://api.k780.com/upload/weather/d/1.gif",*"weather_icon1":"http://api.k780.com/upload/weather/n/7.gif",*"wind":"东风",*"winp":"<3级",*"temp_high":"32",*"temp_low":"25",*"humi_high":"0",*"humi_low":"0",*"weatid":"2",*"weatid1":"8",*"windid":"10",*"winpid":"395",*"weather_iconid":"1",*"weather_iconid1":"7"*}, 这后面类似……*/

然后我们根据这构建对象，根据这段json分析，这可能是俩对象，然后，一个对象是结果集数组[]，一个对象是状态（是否成功），于是，

我拆成了下面两个对象

package com.lvfeng.tool.weather.pojo; import java.util.List; import com.fasterxml.jackson.annotation.JsonIdentityInfo; import com.fasterxml.jackson.annotation.ObjectIdGenerators; /** * @author Administrator * 一周天气对象 * DOC:https://blog.csdn.net/u010457406/article/details/50921632 *https://blog.csdn.net/jxchallenger/article/details/79293772 */@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class,property ="success")public class WeatherWeek { private String success; //是否成功 private List result; //结果集数组 public String getSuccess() {return success; } public void setSuccess(String success) {this.success = success; } public List getResult() {return result; } public void setResult(List result) {this.result = result; }}

package com.lvfeng.tool.weather.pojo; /** * @author LvLvFeng * Weather子类，天气结果的返回值 */public class Result { private String weaid; //本站【调用接口的这个站点】的城市ID编号 private String days; //日期 private String week; //周几 private String cityno; //城市编码 private String citynm; //城市名称 private String cityid; //城市气象ID【标准】 private String temperature; //气温 private String humidity; //湿度【暂未使用】 private String weather; //天气 private String weather_icon; //白天的气象图标 private String weather_icon1; //夜间的气象图标 private String wind; //风向 private String winp; //风力 private String temp_high; //最高气温 private String temp_low; //最低气温 private String humi_high; //温度栏位【弃用】 private String humi_low; //湿度栏位【弃用】 private String weatid; //白天天气ID，可对照weather.wtype接口中weaid private String weatid1; //夜间天气ID，可对照weather.wtype接口中weaid private String windid; //风向ID(暂无对照表) private String winpid; //风力ID(暂无对照表) private String weather_iconid; //气象图标编号(白天),对应weather_icon 1.gif private String weather_iconid1; //气象图标编号(夜间),对应weather_icon1 0.gif public String getWeaid() {return weaid; } public void setWeaid(String weaid) {this.weaid = weaid; } public String getDays() {return days; } public void setDays(String days) {this.days = days; } public String getWeek() {return week; } public void setWeek(String week) {this.week = week; } public String getCityno() {return cityno; } public void setCityno(String cityno) {this.cityno = cityno; } public String getCitynm() {return citynm; } public void setCitynm(String citynm) {this.citynm = citynm; } public String getCityid() {return cityid; } public void setCityid(String cityid) {this.cityid = cityid; } public String getTemperature() {return temperature; } public void setTemperature(String temperature) {this.temperature = temperature; } public String getHumidity() {return humidity; } public void setHumidity(String humidity) {this.humidity = humidity; } public String getWeather() {return weather; } public void setWeather(String weather) {this.weather = weather; } public String getWeather_icon() {return weather_icon; } public void setWeather_icon(String weather_icon) {this.weather_icon = weather_icon; } public String getWeather_icon1() {return weather_icon1; } public void setWeather_icon1(String weather_icon1) {this.weather_icon1 = weather_icon1; } public String getWind() {return wind; } public void setWind(String wind) {this.wind = wind; } public String getWinp() {return winp; } public void setWinp(String winp) {this.winp = winp; } public String getTemp_high() {return temp_high; } public void setTemp_high(String temp_high) {this.temp_high = temp_high; } public String getTemp_low() {return temp_low; } public void setTemp_low(String temp_low) {this.temp_low = temp_low; } public String getHumi_high() {return humi_high; } public void setHumi_high(String humi_high) {this.humi_high = humi_high; } public String getHumi_low() {return humi_low; } public void setHumi_low(String humi_low) {this.humi_low = humi_low; } public String getWeatid() {return weatid; } public void setWeatid(String weatid) {this.weatid = weatid; } public String getWeatid1() {return weatid1; } public void setWeatid1(String weatid1) {this.weatid1 = weatid1; } public String getWindid() {return windid; } public void setWindid(String windid) {this.windid = windid; } public String getWinpid() {return winpid; } public void setWinpid(String winpid) {this.winpid = winpid; } public String getWeather_iconid() {return weather_iconid; } public void setWeather_iconid(String weather_iconid) {this.weather_iconid = weather_iconid; } public String getWeather_iconid1() {return weather_iconid1; } public void setWeather_iconid1(String weather_iconid1) {this.weather_iconid1 = weather_iconid1; } }

开始书写工具类，方便以后调用~

package com.lvfeng.tool.change; import java.io.IOException; import com.fasterxml.jackson.core.JsonParseException; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.databind.JsonMappingException; import com.fasterxml.jackson.databind.ObjectMapper; /** * @author LvLvFeng * 操作json的封装方法 * use:jackson */public class JSONChange { /** 001.json转换成对象* @param:传入对象，json字符串* @return:Object*/ public static Object jsonToObj(Object obj,String jsonStr) throws JsonParseException, JsonMappingException, IOException {ObjectMapper mapper = new ObjectMapper(); return obj = mapper.readValue(jsonStr, obj.getClass()); } /** 002.对象转换成json* @param:传入对象* @return:json字符串*/ public static String objToJson(Object obj) throws JsonProcessingException {ObjectMapper mapper = new ObjectMapper(); return mapper.writeValueAsString(obj); }}

封装完成，写测试类

package com.lvfeng.tool.weather; import com.lvfeng.tool.change.JSONChange; import com.lvfeng.tool.weather.pojo.WeatherWeek; public class TestWeather { public static void main(String[] args) throws Exception{//城市列表，ak,sg,返回格式String res = WeatherAPI.getWeatherWeek("1", WeatherAPI.APP_KEY_WEATHER, WeatherAPI.SIGN_WEATHER, "json"); System.out.println("结果集" + res); String res2 = WeatherAPI.getNowWeather("1", WeatherAPI.APP_KEY_WEATHER, WeatherAPI.SIGN_WEATHER, "json"); System.out.println("结果集2" + res2); WeatherWeek wea = (WeatherWeek)JSONChange.jsonToObj(new WeatherWeek(), res); System.out.println("是否成功？"+wea.getSuccess()+"结果集举例【城市名称】："+wea.getResult().get(0).getCitynm()); System.out.println("---------------------开始反转------------------"); String jsonStr = JSONChange.objToJson(wea); System.out.println("反转结果："+jsonStr); }}

如上，就把查询天气预报的结果转换成俩对象了，然后我们操作对象~啦啦啦！
以上为个人经验，希望能给大家一个参考，也希望大家多多支持脚本之家。