JAVA-JSON工具转换类

package com.util; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; import java.util.Map.Entry; import net.sf.json.JSONArray; import net.sf.json.JSONObject; /** * json转换工具，支持多重嵌套 * @author lijx */ public class JsonUtil { /** * Map转json * @param map * @return */ @SuppressWarnings("unchecked") public static String mapToJson(Map<String, Object> map){ StringBuffer sb = new StringBuffer(); sb.append("{"); int size = map.size(); if(size>0){ int j = map.entrySet().size(); for(Entry<String, Object> entry : map.entrySet()){ String key = entry.getKey(); Object value = entry.getValue(); sb.append("\""); sb.append(key); sb.append("\""); sb.append(":"); if(value==null){ sb.append("\"\""); }else{ String json = ""; if(value instanceof Map<?, ?>){ json = mapToJson((Map<String, Object>)value); sb.append(json); }else if(value instanceof List){ json = listMapToJson((List<Map<String, Object>>)value); sb.append(json); }else{ sb.append("\""); sb.append(value.toString()); sb.append("\""); } } j--; if (j > 0) { sb.append(","); } } } sb.append("}"); return sb.toString(); } /** * List<Map>转json * @param list * @return */ @SuppressWarnings("unchecked") public static String listMapToJson(List<Map<String, Object>> listMap) { StringBuffer sb = new StringBuffer(); int k = listMap.size(); sb.append("["); for (Map<String, Object> map : listMap) { sb.append("{"); int q = map.entrySet().size(); for (Entry<String, Object> entry : map.entrySet()) { String key = entry.getKey(); Object value = entry.getValue(); q--; sb.append("\""); sb.append(key); sb.append("\""); sb.append(":"); if(value==null){ sb.append("\"\""); }else{ String json = ""; if(value instanceof Map<?, ?>){ json = mapToJson((Map<String, Object>)value); sb.append(json); }else if(value instanceof List<?>){ json = listMapToJson((List<Map<String, Object>>)value); sb.append(json); }else{ sb.append("\""); sb.append(value.toString()); sb.append("\""); } } if (q > 0) { sb.append(","); } } k--; sb.append("}"); if (k > 0) { sb.append(","); } } sb.append("]"); return sb.toString(); } /** * json字符串转Map * @param json * @return */ public static Map<String, Object> jsonToMap(String json){ Map<String, Object> map = new HashMap<String, Object>(16); JSONObject jsonObj = JSONObject.fromObject(json); for(Object key : jsonObj.keySet()){ Object value = jsonObj.get(key); String keyStr = String.valueOf(key); String json2 = String.valueOf(value); if(value instanceof JSONObject){ map.put(keyStr, jsonToMap(json2)); }else if(value instanceof JSONArray){ map.put(keyStr, jsonToListMap(json2)); }else{ if("".equals(json2.trim())){ value = null; } map.put(keyStr, value); } } return map; } /** * json字符串转List<Map> * @param json * @return */ public static List<Map<String, Object>> jsonToListMap(String json){ List<Map<String, Object>> listMap = new ArrayList<Map<String,Object>>(); JSONArray jsonArr = JSONArray.fromObject(json); Iterator<?> it = jsonArr.iterator(); while(it.hasNext()){ JSONObject json2 = (JSONObject)it.next(); listMap.add(jsonToMap(String.valueOf(json2))); } return listMap; } public static void main(String[] args) { Map<String, Object> map = new HashMap<String,Object>(16); Map<String, Object> m1 = new HashMap<String,Object>(16); m1.put("photo", null); m1.put("time", "2016-12"); Map<String, Object> m2 = new HashMap<String,Object>(16); m2.put("pic", "pic.jpg"); m2.put("cs", "2222"); m1.put("other", m2); map.put("name", "李哲"); map.put("age", null); map.put("pics", m1); List<Map<String, Object>> list = new ArrayList<Map<String,Object>>(); Map<String, Object> m3 = new HashMap<String,Object>(16); m3.put("data", "1"); m3.put("arr", "arr1"); Map<String, Object> m4 = new HashMap<String,Object>(16); m4.put("data", "2"); m4.put("arr", "arr2"); list.add(m3); list.add(m4); map.put("listData", list); String json = "{\"rspmsg\":{\"rspcode\":0,\"rspdesc\":\"success\"},\"resp\":{\"productTypeList\":[{\"id\":\"19\",\"name\":\"标准光纤\",\"description\":\"高达100台终端上网，送固定IP\",\"linkUrl\":\"http://mall.gmcciot.com/index.php/Home/Product/product_list.html\",\"picUrl\":\"mall-staging.gmcciot.com/Public/Uploads/2018-01-19/5a61695e210f1.jpg\"}]}}"; System.out.println(jsonToMap(json)); } }