JsonUtil工具類

package org.hr.util;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import net.sf.ezmorph.object.DateMorpher;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import net.sf.json.JsonConfig;
import net.sf.json.util.JSONUtils;

/**
 * json轉換為java對象
 * @author CHH
 *
 */

public class JsonUtil {  
      
    /**頁面傳至后台時，json數據在request的參數名稱*/  
    public final static String JSON_ATTRIBUTE = "json";  
    public final static String JSON_ATTRIBUTE1 = "json1";  
    public final static String JSON_ATTRIBUTE2 = "json2";  
    public final static String JSON_ATTRIBUTE3 = "json3";  
    public final static String JSON_ATTRIBUTE4 = "json4";  
      
    /** 
     * 從一個JSON 對象字符格式中得到一個java對象，形如： 
     * {"id" : idValue, "name" : nameValue, "aBean" : {"aBeanId" : aBeanIdValue, ...}} 
     * @param object 
     * @param clazz 
     * @return 
     */  
    public static Object getDTO(String jsonString, Class clazz){  
        JSONObject jsonObject = null;  
        try{  
            setDataFormat2JAVA();   
            jsonObject = JSONObject.fromObject(jsonString);  
        }catch(Exception e){  
            e.printStackTrace();  
        }  
        return JSONObject.toBean(jsonObject, clazz);  
    }  
      
    /** 
     * 從一個JSON 對象字符格式中得到一個java對象，其中beansList是一類的集合，形如： 
     * {"id" : idValue, "name" : nameValue, "aBean" : {"aBeanId" : aBeanIdValue, ...}, 
     * beansList:[{}, {}, ...]} 
     * @param jsonString 
     * @param clazz 
     * @param map 集合屬性的類型 (key : 集合屬性名, value : 集合屬性類型class) eg: ("beansList" : Bean.class) 
     * @return 
     */  
    public static Object getDTO(String jsonString, Class clazz, Map map){  
        JSONObject jsonObject = null;  
        try{  
            setDataFormat2JAVA();   
            jsonObject = JSONObject.fromObject(jsonString);  
        }catch(Exception e){  
            e.printStackTrace();  
        }  
        return JSONObject.toBean(jsonObject, clazz, map);  
    }  
      
    /** 
     * 從一個JSON數組得到一個java對象數組，形如： 
     * [{"id" : idValue, "name" : nameValue}, {"id" : idValue, "name" : nameValue}, ...] 
     * @param object 
     * @param clazz 
     * @return 
     */  
    public static Object[] getDTOArray(String jsonString, Class clazz){  
        setDataFormat2JAVA();  
        JSONArray array = JSONArray.fromObject(jsonString);  
        Object[] obj = new Object[array.size()];  
        for(int i = 0; i < array.size(); i++){  
            JSONObject jsonObject = array.getJSONObject(i);  
            obj[i] = JSONObject.toBean(jsonObject, clazz);  
        }  
        return obj;  
    }  
      
    /** 
     * 從一個JSON數組得到一個java對象數組，形如： 
     * [{"id" : idValue, "name" : nameValue}, {"id" : idValue, "name" : nameValue}, ...] 
     * @param object 
     * @param clazz 
     * @param map 
     * @return 
     */  
    public static Object[] getDTOArray(String jsonString, Class clazz, Map map){  
        setDataFormat2JAVA();  
        JSONArray array = JSONArray.fromObject(jsonString);  
        Object[] obj = new Object[array.size()];  
        for(int i = 0; i < array.size(); i++){  
            JSONObject jsonObject = array.getJSONObject(i);  
            obj[i] = JSONObject.toBean(jsonObject, clazz, map);  
        }  
        return obj;  
    }  
      
    /** 
     * 從一個JSON數組得到一個java對象集合 
     * @param object 
     * @param clazz 
     * @return 
     */  
    public static List getDTOList(String jsonString, Class clazz){  
        setDataFormat2JAVA();  
        JSONArray array = JSONArray.fromObject(jsonString);  
        List list = new ArrayList();  
        for(Iterator iter = array.iterator(); iter.hasNext();){  
            JSONObject jsonObject = (JSONObject)iter.next();  
            list.add(JSONObject.toBean(jsonObject, clazz));  
        }  
        return list;  
    }  
      
    /** 
     * 從一個JSON數組得到一個java對象集合，其中對象中包含有集合屬性 
     * @param object 
     * @param clazz 
     * @param map 集合屬性的類型 
     * @return 
     */  
    public static List getDTOList(String jsonString, Class clazz, Map map){  
        setDataFormat2JAVA();  
        JSONArray array = JSONArray.fromObject(jsonString);  
        List list = new ArrayList();  
        for(Iterator iter = array.iterator(); iter.hasNext();){  
            JSONObject jsonObject = (JSONObject)iter.next();  
            list.add(JSONObject.toBean(jsonObject, clazz, map));  
        }  
        return list;  
    }  
      
    /** 
     * 從json HASH表達式中獲取一個map，該map支持嵌套功能 
     * 形如：{"id" : "johncon", "name" : "小強"} 
     * 注意commons-collections版本，必須包含org.apache.commons.collections.map.MultiKeyMap 
     * @param object 
     * @return 
     */  
    public static Map getMapFromJson(String jsonString) {  
        setDataFormat2JAVA();  
        JSONObject jsonObject = JSONObject.fromObject(jsonString);  
        Map map = new HashMap();  
        for(Iterator iter = jsonObject.keys(); iter.hasNext();){  
            String key = (String)iter.next();  
            map.put(key, jsonObject.get(key));  
        }  
        return map;  
    }  
      
    /** 
     * 從json數組中得到相應java數組 
     * json形如：["123", "456"] 
     * @param jsonString 
     * @return 
     */  
    public static Object[] getObjectArrayFromJson(String jsonString) {  
        JSONArray jsonArray = JSONArray.fromObject(jsonString);  
        return jsonArray.toArray();  
    }  
  
  
    /** 
     * 把數據對象轉換成json字符串 
     * DTO對象形如：{"id" : idValue, "name" : nameValue, ...} 
     * 數組對象形如：[{}, {}, {}, ...] 
     * map對象形如：{key1 : {"id" : idValue, "name" : nameValue, ...}, key2 : {}, ...} 
     * @param object 
     * @return 
     */  
    public static String getJSONString(Object object) throws Exception{  
        String jsonString = null;  
        //日期值處理器  
        JsonConfig jsonConfig = new JsonConfig();  
        jsonConfig.registerJsonValueProcessor(java.util.Date.class, new JsonDateValueUtil());  
        if(object != null){  
            if(object instanceof Collection || object instanceof Object[]){  
                jsonString = JSONArray.fromObject(object, jsonConfig).toString();  
            }else{  
                jsonString = JSONObject.fromObject(object, jsonConfig).toString();  
            }  
        }  
        return jsonString == null ? "{}" : jsonString;  
    }  
      
    private static void setDataFormat2JAVA(){  
        //設定日期轉換格式  
        JSONUtils.getMorpherRegistry().registerMorpher(new DateMorpher(new String[] {"yyyy-MM-dd", "yyyy-MM-dd HH:mm:ss"}));  
    }  
      
    public static void main(String[] arg) throws Exception{  
        String s = "{status : 'success'}";  
        System.out.println(" object : " + JsonUtil.getJSONString(s));  
    }  
}