开发：随笔记录之 Json字符串与 List、HashMap对象的转换

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跌底 2017-12-22 12:13:18 博主文章分类：java

文章标签 java 文章分类 Java 后端开发

import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Map.Entry; import net.sf.json.JSONArray; import net.sf.json.JSONObject; import net.sf.json.JsonConfig; import net.sf.json.util.JSONUtils;

public class JsonParser {

/**

json字符串转成 map
@param jsonStr
@return
@throws Exception */ public static HashMap<String, JsonValue> parse(String jsonStr) { if (jsonStr == null || "".equals(jsonStr)) { return null; } HashMap<String, JsonValue> retMap = null; try { retMap = new HashMap<String, JsonValue>(); JSONObject json = JSONObject.fromObject(jsonStr); Map<String, Object> tmpMap = (Map<String, Object>) JSONObject .toBean(json, Map.class); for (Map.Entry<String, Object> entry : tmpMap.entrySet()) { JsonValue tmp = parseRec(entry.getValue(), 0); retMap.put(entry.getKey(), tmp); } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } return retMap; }

/**

json字符串转成 List
@param jsonStr
@return
@throws Exception */ public static List<HashMap<String, JsonValue>> parseList(String jsonStr) { if (jsonStr == null || "".equals(jsonStr)) { return null; }

List<HashMap<String, JsonValue>> retList = new ArrayList<HashMap<String, JsonValue>>();

JSONArray data = JSONArray.fromObject(jsonStr); for (int i = 0; i < data.size(); i++) { HashMap<String, JsonValue> retMap = new HashMap<String, JsonValue>();

JSONObject json = (JSONObject) data.get(i); Map<String, Object> tmpMap = (Map<String, Object>) JSONObject .toBean(json, Map.class);

for (Map.Entry<String, Object> entry : tmpMap.entrySet()) { JsonValue tmp = parseRec(entry.getValue(), 0); retMap.put(entry.getKey(), tmp); } retList.add(retMap); } return retList; }

/**

HashMap<String, JsonValue> map 转成 json字符串
@param jsonStr
@return
@throws Exception */ public static String parse(HashMap<String, JsonValue> map) { HashMap<String, Object> retMap = new HashMap<String, Object>(); for (Map.Entry<String, JsonValue> entry : map.entrySet()) { Object tmp = parseJsonValueRec(entry.getValue(), 0); retMap.put(entry.getKey(), tmp); } JsonConfig jc = new JsonConfig(); return JSONObject.fromObject(retMap, jc).toString(); }

/**

List<HashMap<String, JsonValue>> list 转成 json字符串
@param jsonStr
@return
@throws Exception */ public static String parse(List<HashMap<String, JsonValue>> list) { List<HashMap<String, Object>> tmpList = new ArrayList<HashMap<String, Object>>();

for (HashMap<String, JsonValue> map : list) { HashMap<String, Object> retMap = new HashMap<String, Object>(); for (Map.Entry<String, JsonValue> entry : map.entrySet()) { Object tmp = parseJsonValueRec(entry.getValue(), 0); retMap.put(entry.getKey(), tmp); } tmpList.add(retMap); } JSONArray json = new JSONArray(); json.addAll(tmpList); return json.toString(); }

/**

构建json
@param map
@return */ public static String parse(Map map) { JsonConfig jc = new JsonConfig(); return JSONObject.fromObject(map, jc).toString(); }
```
对了，json的版本我用的是json-lib-2.4-jdk15.jar
```