java实现字符串和LIST，MAP转换

需要下载第三方的jar ：net.sf.json

import java.io.BufferedReader; import java.io.InputStream; import java.io.InputStreamReader; import java.net.URL; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import java.util.Map; import java.util.Set; import org.apache.commons.collections.map.ListOrderedMap; import net.sf.json.JSONArray; import net.sf.json.JSONObject; /** * * 处理json的工具类. * <br>本类为处理json的工具类 * @author slj */ public class JsonTools { /** * * json转换list. * <br>详细说明 * @param jsonStr json字符串 * @return * @return List<Map<String,Object>> list * @throws * @author slj * @date 2013年12月24日 下午1:08:03 */ public static List<Map<String, Object>> parseJSON2List(String jsonStr){ JSONArray jsonArr = JSONArray.fromObject(jsonStr); List<Map<String, Object>> list = new ArrayList<Map<String,Object>>(); Iterator<JSONObject> it = jsonArr.iterator(); while(it.hasNext()){ JSONObject json2 = it.next(); list.add(parseJSON2Map(json2.toString())); } return list; } /** * * json转换map. * <br>详细说明 * @param jsonStr json字符串 * @return * @return Map<String,Object> 集合 * @throws * @author slj */ public static Map<String, Object> parseJSON2Map(String jsonStr){ ListOrderedMap map = new ListOrderedMap(); //最外层解析 JSONObject json = JSONObject.fromObject(jsonStr); for(Object k : json.keySet()){ Object v = json.get(k); //如果内层还是数组的话，继续解析 if(v instanceof JSONArray){ List<Map<String, Object>> list = new ArrayList<Map<String,Object>>(); Iterator<JSONObject> it = ((JSONArray)v).iterator(); while(it.hasNext()){ JSONObject json2 = it.next(); list.add(parseJSON2Map(json2.toString())); } map.put(k.toString(), list); } else { map.put(k.toString(), v); } } return map; } /** * * 通过HTTP获取JSON数据. * <br>通过HTTP获取JSON数据返回list * @param url 链接 * @return * @return List<Map<String,Object>> list * @throws * @author slj */ public static List<Map<String, Object>> getListByUrl(String url){ try { //通过HTTP获取JSON数据 InputStream in = new URL(url).openStream(); BufferedReader reader = new BufferedReader(new InputStreamReader(in)); StringBuilder sb = new StringBuilder(); String line; while((line=reader.readLine())!=null){ sb.append(line); } return parseJSON2List(sb.toString()); } catch (Exception e) { e.printStackTrace(); } return null; } /** * * 通过HTTP获取JSON数据. * <br>通过HTTP获取JSON数据返回map * @param url 链接 * @return * @return Map<String,Object> 集合 * @throws * @author slj */ public static Map<String, Object> getMapByUrl(String url){ try { //通过HTTP获取JSON数据 InputStream in = new URL(url).openStream(); BufferedReader reader = new BufferedReader(new InputStreamReader(in)); StringBuilder sb = new StringBuilder(); String line; while((line=reader.readLine())!=null){ sb.append(line); } return parseJSON2Map(sb.toString()); } catch (Exception e) { e.printStackTrace(); } return null; } /** * * map转换json. * <br>详细说明 * @param map 集合 * @return * @return String json字符串 * @throws * @author slj */ public static String mapToJson(Map<String, String> map) { Set<String> keys = map.keySet(); String key = ""; String value = ""; StringBuffer jsonBuffer = new StringBuffer(); jsonBuffer.append("{"); for (Iterator<String> it = keys.iterator(); it.hasNext();) { key = (String) it.next(); value = map.get(key); jsonBuffer.append(key + ":" +"\""+ value+"\""); if (it.hasNext()) { jsonBuffer.append(","); } } jsonBuffer.append("}"); return jsonBuffer.toString(); } //test public static void main(String[] args) { String url = "http://..."; List<Map<String,Object>> list = getListByUrl(url); System.out.println(list); } }

比如解析：

{"data":[{"id":"402880566092af74016092ba010f0026_151429025888228961","WI_ACTIVITY_ID_":"manuscripts","WI_ID_":"151429025888228961","workflowName":"志书编纂1","tableId":"8a7a543d5ccf1bb3015ccf412169006d","workflowId":"8a7aef3d5cd871bf015cd876c65b0000","workflowCode":"ZSBZ_NEW","PROCESS_INSTANCE_ID_":"151429025753518344","WI_STATUS_KEY_":"12","explain":"超级管理员申请的2017-12-26 20:09:12志书编纂1"},{"id":"83838a7a5fec0991015fec0b11d70010_151149367104810227","WI_ACTIVITY_ID_":"taskAssigned","WI_ID_":"151149367104810227","workflowName":"专题编研","tableId":"8a8aacd9564a3a1901564a882a6c0022","workflowId":"297ee40a56ca38590156caa6a0bb0008","workflowCode":"ZTBY_ZT","PROCESS_INSTANCE_ID_":"151149367010400495","WI_STATUS_KEY_":"12","explain":"超级管理员申请的2017-11-24 11:21:09专题编研"},{"id":"948181865e08e7b0015e091ea117011b_150339155625410132","WI_ACTIVITY_ID_":"activity2","WI_ID_":"150339155625410132","workflowName":"退回整理库","tableId":"402809815894218c01589560c7f90006","workflowId":"8383849458b8d25a0158b8dc9daa0000","workflowCode":"RETURNARRANGE","PROCESS_INSTANCE_ID_":"150339155603600640","WI_STATUS_KEY_":"12","explain":"超级管理员申请的2017-08-22 16:45:55退回整理库"}],"pageNumber":1,"pageSize":3,"total":3,"totalPages":1}

获取其中的data部分转换为List<Map<String,Object>>

    public List<Map<String,Object>> parseStringToListMap(String res) throws Exception{
        List<Map<String,Object>> list=new ArrayList<Map<String,Object>>();
        JSONObject jsonResult = new JSONObject(res);
        Iterator<String> nameItr = jsonResult.keys();
        while (nameItr.hasNext()) {
            String name = nameItr.next();
            if(name.equals("data")){
                String data=jsonResult.getString(name);
                JSONArray jsonArr = JSONArray.fromObject(data);
                for(int s=0;s<jsonArr.size();s++){//便利取到每个map
                    Map<String,Object> map = new HashMap<String,Object>();
                    String vas= jsonArr.get(s)==null?"":jsonArr.get(s).toString();
                    JSONObject jr=new JSONObject(vas);
                    Iterator<String> nir = jr.keys();
                    while (nir.hasNext()) {//取到map里的每个值
                        String json2 = nir.next();
                        String value= jr.getString(json2);
                        map.put(json2, value);
                    }
                    list.add(map);
                }
            }
        }
        return list;
    }