JSON工具類JSONUtil

package com.archermind.util;

import java.lang.reflect.Array;

import java.lang.reflect.Method;

import java.util.Collection;

import java.util.Iterator;

import java.util.Map;

import org.json.JSONArray;

import org.json.JSONException;

import org.json.JSONObject;

import org.json.JSONString;

public class JSONUtil{

   private static JSONUtil instance = null;

   public JSONUtil(){}

    protected Object proxyCheck(Object bean){

        return bean;

    }

    static public String toJSONString(Object obj) throws JSONException{

        return toJSONString(obj, false);

    }

    static public String toJSONString(Object obj, boolean useClassConvert) throws JSONException{

        if(instance == null)

            instance = new JSONUtil();

        return instance.getJSONObject(obj, useClassConvert).toString();

    }

    private String getJSONArray(Object arrayObj, boolean useClassConvert) throws JSONException{

        if(arrayObj == null)

            return "null";

        arrayObj = proxyCheck(arrayObj);

        JSONArray jSONArray = new JSONArray();

        if(arrayObj instanceof Collection){

            Iterator iterator = ((Collection)arrayObj).iterator();

            while(iterator.hasNext()){

                Object rowObj = iterator.next();

                if(rowObj == null)

                    jSONArray.put(new JSONStringObject(null));

                else if(rowObj.getClass().isArray() || rowObj instanceof Collection)

                    jSONArray.put(getJSONArray(rowObj, useClassConvert));

                else

                    jSONArray.put(getJSONObject(rowObj, useClassConvert));

            }

        }

        if(arrayObj.getClass().isArray()){

            int arrayLength = Array.getLength(arrayObj);

            for(int i = 0; i < arrayLength; i ++){

                Object rowObj = Array.get(arrayObj, i);

                if(rowObj == null)

                    jSONArray.put(new JSONStringObject(null));

                else if(rowObj.getClass().isArray() || rowObj instanceof Collection)

                    jSONArray.put(getJSONArray(rowObj, useClassConvert));

                else

                    jSONArray.put(getJSONObject(rowObj, useClassConvert));

            }

        }

        return jSONArray.toString();

    }

    JSONStringObject getJSONObject(Object value, boolean useClassConvert) throws JSONException{

        if (value == null) {

            return new JSONStringObject("null");

        }

        value = proxyCheck(value);

        if (value instanceof JSONString) {

            Object o;

            try {

                o = ((JSONString)value).toJSONString();

            } catch (Exception e) {

                throw new JSONException(e);

            }

            throw new JSONException("Bad value from toJSONString: " + o);

        }

        if (value instanceof Number){

            return new JSONStringObject(JSONObject.numberToString((Number) value));

        }

        if (value instanceof Boolean || value instanceof JSONObject ||

                value instanceof JSONArray) {

            return new JSONStringObject(value.toString());

        }

        if (value instanceof String)

            return new JSONStringObject(JSONObject.quote(value.toString()));

        if (value instanceof Map) {

            JSONObject jSONObject = new JSONObject();

            Iterator iterator = ((Map)value).keySet().iterator();

            while(iterator.hasNext()){

                String key = iterator.next().toString();

                Object valueObj = ((Map)value).get(key);

                jSONObject.put(key, getJSONObject(valueObj, useClassConvert));

            }

            return new JSONStringObject(jSONObject.toString());

        }

        //class

        if(value instanceof Class)

            return new JSONStringObject(JSONObject.quote(((Class)value).getSimpleName()));

        if (value instanceof Collection || value.getClass().isArray()) {

            return new JSONStringObject(getJSONArray(proxyCheck(value), useClassConvert));

        }

        return reflectObject(value, useClassConvert);

    }

    private JSONStringObject reflectObject(Object bean, boolean useClassConvert) {

        JSONObject jSONObject = new JSONObject();

        Class<? extends Object> klass = bean.getClass();

        Method[] methods = klass.getMethods();

        for (int i = 0; i < methods.length; i += 1) {

            try {

                Method method = methods[i];

                String name = method.getName();

                String key = "";

                if (name.startsWith("get")) {

                    key = name.substring(3);

                } else if (name.startsWith("is")) {

                    key = name.substring(2);

                }

                if (key.length() > 0 &&

                        Character.isUpperCase(key.charAt(0)) &&

                        method.getParameterTypes().length == 0) {

                    if (key.length() == 1) {

                        key = key.toLowerCase();

                    } else if (!Character.isUpperCase(key.charAt(1))) {

                        key = key.substring(0, 1).toLowerCase() +

                            key.substring(1);

                    }

                    Object elementObj = method.invoke(bean, null);

                    if(!useClassConvert && elementObj instanceof Class)

                        continue;

                    jSONObject.put(key, getJSONObject(elementObj, useClassConvert));

                }

            } catch (Exception e) {

            }

        }

        return new JSONStringObject(jSONObject.toString());

    }

}