一、前言
这次项目中遇到了一个这样的需求，把下面数据解析到我下面的对象里去。
json 文件
[ { "categories": [ "美食，小吃快餐" ], "coordinate": { "address": "王府井大街138号新东安广场3层328", "area": "东安市场", "area_id": "jk238eewf0k", "city": "北京市", "city_code": "110100", "district": "东城区", "district_code": "110101", "floor": "3", "latitude": "39.91456", "longitude": "116.41155", "province": "北京市", "province_code": "110000" }, "name": "探鱼", "phone": "010-65280328", "poi_id": "d7s8f6s6212" }, { "categories": [ "美食，面包甜点" ], "coordinate": { "address": "丰台北路18号院恒泰广场F6楼", "area": "恒泰广场", "area_id": "ji8sgg3b32o", "city": "北京市", "city_code": "110100", "district": "丰台区", "district_code": "110106", "floor": "6", "latitude": "39.86608", "longitude": "116.30516", "province": "北京市", "province_code": "110000" }, "name": "好客来", "phone": "010-65280221", "poi_id": "3g97sg8sd67" }]
实体对象：
public class LocatorData { // 分类 private String categories; // 商圈 private String area; // 商圈id private String areaId; // 省份 private String province; // 省份code private String provinceCode; // 城市 private String city; // 城市code private String cityCode; // 区县 private String district; // 区县code private String districtCode; // 楼层 private String floor; // 经度 private Double latitude; // 维度 private Double longitude; // 店铺名称 private String name; // 店铺地址 private String address; // 店铺电话 private String phone; // 店铺id private String poiId;}
不知道小伙伴有没有发现，我这里只是一个对象，没有一对多的关系哈，要的就是这样的效果。
但 json 文件里有个 coordinate 对象，而我实体对象不需要这个字段。那也没关系，一步步解析就完事了。
@RestControllerpublic class ParseController {private static final Logger LOGGER = LoggerFactory.getLogger(EasyExcelController.class);@PostMapping(value = "/arrayObjectNestingParse",produces = "application/json;charset=UTF-8") public ReturnT<String> arrayObjectNestingParse(@RequestParam(value = "jsonFile") MultipartFile jsonFile) { if (jsonFile == null) { return new ReturnT<>(ReturnT.BAD_REQUEST, "Params can not be null"); } InputStream is = null; BufferedReader br = null; StringBuffer sb = new StringBuffer(); String str = null; try { is = jsonFile.getInputStream(); br = new BufferedReader(new InputStreamReader(is)); while ((str = br.readLine()) != null) { sb.append(str); } } catch (IOException e) { e.printStackTrace(); } finally { try { br.close(); } catch (IOException e) { e.printStackTrace(); } } List<LocatorData> locatorDataList = new ArrayList<>(); JSONArray jsonArray = JSONArray.parseArray(sb.toString()); for (int i = 0; i < jsonArray.size(); i++) { LocatorData locatorData = new LocatorData(); JSONObject jsonObject = jsonArray.getJSONObject(i); String categories = jsonObject.getString("categories"); String coordinate = jsonObject.getString("coordinate"); JSONObject coordinateObj = JSONObject.parseObject(coordinate); String address = coordinateObj.getString("address"); String area = coordinateObj.getString("area"); String areaId = coordinateObj.getString("area_id"); String city = coordinateObj.getString("city"); String cityCode = coordinateObj.getString("city_code"); String district = coordinateObj.getString("district"); String districtCode = coordinateObj.getString("district_code"); String floor = coordinateObj.getString("floor"); String latitude = coordinateObj.getString("latitude"); String longitude = coordinateObj.getString("longitude"); String province = coordinateObj.getString("province"); String provinceCode = coordinateObj.getString("province_code"); String name = jsonObject.getString("name"); String phone = jsonObject.getString("phone"); String poiId = jsonObject.getString("poi_id"); locatorData.setCategories(categories); locatorData.setAddress(address); locatorData.setArea(area); locatorData.setAreaId(areaId); locatorData.setProvince(province); locatorData.setProvinceCode(provinceCode); locatorData.setCity(city); locatorData.setCityCode(cityCode); locatorData.setDistrict(district); locatorData.setDistrictCode(districtCode); locatorData.setFloor(floor); locatorData.setLatitude(Double.parseDouble(latitude)); locatorData.setLongitude(Double.parseDouble(longitude)); locatorData.setName(name); locatorData.setPhone(phone); locatorData.setPoiId(poiId); locatorDataList.add(locatorData); } LOGGER.info("locatorDataList: " + JSON.toJSONString(locatorDataList)); return new ReturnT<>(ReturnT.SUCCESS, JSON.toJSONString(locatorDataList)); }}
日志打印：
2020-01-07 00:39:30.284 [http-nio-8080-exec-3] INFO c.r.springbootdemo.controller.EasyExcelController-locatorDataList: [{“address”:”王府井大街138号新东安广场3层328″,”area”:”东安市场”,”areaId”:”jk238eewf0k”,”categories”:”[\”美食，小吃快餐\”]”,”city”:”北京市”,”cityCode”:”110100″,”district”:”东城区”,”districtCode”:”110101″,”floor”:”3″,”latitude”:39.91456,”longitude”:116.41155,”name”:”探鱼”,”phone”:”010-65280328″,”poiId”:”d7s8f6s6212″,”province”:”北京市”,”provinceCode”:”110000″},{“address”:”丰台北路18号院恒泰广场F6楼”,”area”:”恒泰广场”,”areaId”:”ji8sgg3b32o”,”categories”:”[\”美食，面包甜点\”]”,”city”:”北京市”,”cityCode”:”110100″,”district”:”丰台区”,”districtCode”:”110106″,”floor”:”6″,”latitude”:39.86608,”longitude”:116.30516,”name”:”好客来”,”phone”:”010-65280221″,”poiId”:”3g97sg8sd67″,”province”:”北京市”,”provinceCode”:”110000″}]
我们用工具转换一下看的更清晰一点：
[ { "address": "王府井大街138号新东安广场3层328", "area": "东安市场", "areaId": "jk238eewf0k", "categories": "["美食，小吃快餐"]", "city": "北京市", "cityCode": "110100", "district": "东城区", "districtCode": "110101", "floor": "3", "latitude": 39.91456, "longitude": 116.41155, "name": "探鱼", "phone": "010-65280328", "poiId": "d7s8f6s6212", "province": "北京市", "provinceCode": "110000" }, { "address": "丰台北路18号院恒泰广场F6楼", "area": "恒泰广场", "areaId": "ji8sgg3b32o", "categories": "["美食，面包甜点"]", "city": "北京市", "cityCode": "110100", "district": "丰台区", "districtCode": "110106", "floor": "6", "latitude": 39.86608, "longitude": 116.30516, "name": "好客来", "phone": "010-65280221", "poiId": "3g97sg8sd67", "province": "北京市", "provinceCode": "110000" }]
json数组和List集合转换总结
//方法一,将json解析后赋给单独的元素String jstr="{'json':'jsonvalue','bool':true,'int':1,'double':'20.5'}";JSONObject json=JSONObject.fromObject(jstr);boolean bool=json.getBoolean("bool");int i=json.getInt("int");double d=json.getDouble("double");String value=json.getString("json");System.out.println("bool="+String.valueOf(bool)+"\tjson="+value+"\tint="+i+"\tdouble="+d);
//方法二,json对象和bean对象之间相互转换//假如你是有一个bean对象class User{private String name;private String psw;//封装getter/setter省略}//把一个json对象变成userString u="{'name':'sail331x','psw':'123456789'}";//用user对象接收json中的元素User user=(User)JSONObject.toBean(JSONObject.fromObject(u),User.class);//把一个user变成json对象：JSONObject juser=JSONObject.fromObject(user);//json字符串jstrString jstr=juser.toString();
//方法三,json对象直接转list集合、list集合转json对象//声明一个Person 实体类：import java.util.Date;public class Person { String id; int age; String name; Date birthday; //get,set方法省略}//测试json数据转换import java.util.Iterator;import java.util.List;import org.junit.Test;import net.sf.json.JSONArray;import net.sf.json.JsonConfig;public class JsonToList { public static void main(String[] args) { String json="[{'name':'zhuangsan','age':18},{'name':'lisi','age':20}]"; JSONArray jsonarray = JSONArray.fromObject(json); System.out.println(jsonarray); List list = (List)JSONArray.toCollection(jsonarray, Person.class); Iterator it = list.iterator(); while(it.hasNext()){ Person p = (Person)it.next(); System.out.println(p.getAge()); } } @Test public void jsonToList1(){ String json="[{'name':'zhuangsan','age':18},{'name':'lisi','age':20}]"; JSONArray jsonarray = JSONArray.fromObject(json); System.out.println(jsonarray); List list = (List)JSONArray.toList(jsonarray, Person.class); Iterator it = list.iterator(); while(it.hasNext()){ Person p = (Person)it.next(); System.out.println(p.getAge()); } } @Test public void jsonToList2(){ String json="[{'name':'zhuangsan','age':20},{'name':'lisi','age':18}]"; JSONArray jsonarray = JSONArray.fromObject(json); System.out.println(jsonarray); System.out.println("------------"); List list = (List)JSONArray.toList(jsonarray, new Person(), new JsonConfig()); Iterator it = list.iterator(); while(it.hasNext()){ Person p = (Person)it.next(); System.out.println(p.getAge()); } }}//将list对象转为JSON字符串数组：import java.util.LinkedList;import java.util.List;import net.sf.json.JSONArray;public class ListToJson { public static void main(String[] args) { List list = new LinkedList(); for(int i=0;i<3;i++){ Person p = new Person(); p.setAge(i); p.setName("name"+i); list.add(p); } JSONArray jsonarray = JSONArray.fromObject(list); System.out.println(jsonarray); }}
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。
其实每一朵花，都有它自己的生命，
