开发：随笔记录之Json字符串与List、HashMap对象的转换

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 parse(String jsonStr) {
if (jsOnStr== null || "".equals(jsonStr)) { return null; }
HashMap retMap = null;
try {
retMap = new HashMap();
JSONObject json = JSONObject.fromObject(jsonStr);
Map tmpMap = (Map) JSONObject
.toBean(json, Map.class);
for (Map.Entry 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> parseList(String jsonStr) {
if (jsOnStr== null || "".equals(jsonStr)) { return null; }


List> retList = new ArrayList>();


JSONArray data = JSONArray.fromObject(jsonStr);
for (int i = 0; i HashMap retMap = new HashMap();


JSONObject json = (JSONObject) data.get(i);
Map tmpMap = (Map) JSONObject
.toBean(json, Map.class);


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


/**
* HashMap map 转成 json字符串
* 
* @param jsonStr
* @return
* @throws Exception
*/
public static String parse(HashMap map) {
HashMap retMap = new HashMap();
for (Map.Entry 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> list 转成 json字符串
* 
* @param jsonStr
* @return
* @throws Exception
*/
public static String parse(List> list) {
List> tmpList = new ArrayList>();


for (HashMap map : list) {
HashMap retMap = new HashMap();
for (Map.Entry 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