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);
    }
}