Json转化工具类

package com.rest.ful.utils;import java.io.BufferedReader;import java.io.InputStream;import java.io.InputStreamReader;import java.net.URL;import java.util.ArrayList;import java.util.Date;import java.util.HashMap;import java.util.Iterator;import java.util.List;import java.util.Map;import java.util.Set;import com.alibaba.fastjson.JSON;import com.alibaba.fastjson.JSONArray;import com.alibaba.fastjson.JSONObject;import com.alibaba.fastjson.serializer.SerializeConfig;import com.alibaba.fastjson.serializer.SimpleDateFormatSerializer;/** * Json工具类 * @author  zlzhaoe * @version [版本号, 2017年5月8日] * @see  [相关类/方法] * @since  [产品/模块版本] */public class JsonUtils{    private static SerializeConfig mapping = new SerializeConfig();    private static String dateFormat;    static    {        dateFormat = "yyyy-MM-dd HH:mm:ss";        mapping.put(Date.class, new SimpleDateFormatSerializer(dateFormat));    }    /**     *      * <把任意对象转换为json字符串 >     *      * @param obj 任意对象     * @return json字符串     */    public static String object2json(Object obj)    {        if (obj == null)        {            return "{}";        }        return JSON.toJSONString(obj, mapping);    }    /**     *      * <把bean对象转换为json字符串>     *      * @param bean bean对象     * @return json字符串     */    public static String bean2json(Object bean)    {        return object2json(bean);    }    /**     *      * <把list对象转换为json字符串>     *      * @param list list对象     * @return json字符串     */    public static String list2json(List<?> list)    {        return object2json(list);    }    /**     *      * <把数组对象转换为json字符串>     *      * @param array 数组对象     * @return json字符串     */    public static String array2json(Object[] array)    {        return object2json(array);    }    /**     *      * <把数组对象转换为json字符串>     *      * @param map map对象     * @return json字符串     */    public static String map2json(Map<?, ?> map)    {        return object2json(map);    }    /**     *      * <把set对象转换为json字符串>     *      * @param set set对象     * @return json字符串     */    public static String set2json(Set<?> set)    {        return object2json(set);    }    /**     *      * <把String对象转换为json字符串>     *      * @param s String对象     * @return json字符串     */    public static String string2json(String s)    {        if (null == s)        {            return "";        }        StringBuilder sb = new StringBuilder();        for (int i = 0; i < s.length(); i++)        {            char ch = s.charAt(i);            switch (ch)            {                case '"':                    sb.append("\\\\\"");                    break;                case '\\':                    sb.append("\\\\");                    break;                case '\b':                    sb.append("\\b");                    break;                case '\f':                    sb.append("\\f");                    break;                case '\n':                    sb.append("\\n");                    break;                case '\r':                    sb.append("\\r");                    break;                case '\t':                    sb.append("\\t");                    break;                case '/':                    sb.append("\\/");                    break;                default:                    if (ch >= '\u0000' && ch <= '\u001F')                    {                        String ss = Integer.toHexString(ch);                        sb.append("\\u");                        for (int k = 0; k < 4 - ss.length(); k++)                        {                            sb.append('0');                        }                        sb.append(ss.toUpperCase());                    }                    else                    {                        sb.append(ch);                    }            }        }        return sb.toString();    }    public static List<Map<String, Object>> parseJSON2List(String jsonStr)    {        JSONArray jsonArr = JSONArray.parseArray(jsonStr);        List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();        Iterator<Object> it = jsonArr.iterator();        while (it.hasNext())        {            JSONObject json2 = JSONObject.parseObject(JSON.toJSONString(it.next(), mapping));            list.add(parseJSON2Map(json2.toString()));        }        return list;    }    public static Map<String, Object> parseJSON2Map(String jsonStr)    {        Map<String, Object> map = new HashMap<String, Object>();        // 最外层解析        JSONObject json = JSONObject.parseObject(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<Object> it = ((JSONArray)v).iterator();                while (it.hasNext())                {                    JSONObject json2 = JSONObject.parseObject(JSON.toJSONString(it.next(), mapping));                    list.add(parseJSON2Map(json2.toString()));                }                map.put(k.toString(), list);            }            else            {                map.put(k.toString(), v);            }        }        return map;    }    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;    }    public static void main(String[] a)    {        List<Object> list = new ArrayList<Object>();        list.add(1);        list.add(2);        list.add(3);        list.add(new Date());        list.add(15);        String aa = JSON.toJSONString(list, mapping);        System.out.println(aa);    }}