org.foxbpm.web.common.util.JSONUtil.java Source code

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Here is the source code for org.foxbpm.web.common.util.JSONUtil.java

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/**
 * Copyright 1996-2014 FoxBPM ORG.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 * @author yangguangftlp
 */
package org.foxbpm.web.common.util;

import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

/**
 * JSON
 * @author yangguangftlp
   @date 2014611
 */
public class JSONUtil {

    /**
     * JSONNULL
     */
    public static final Object NULL = JSONObject.NULL;

    /**  {@code JSON} ? - <code>"{}"</code> */
    public static final String EMPTY_JSON = "{}";
    /**  {@code JSON} (?)? - {@code "[]"} */
    public static final String EMPTY_JSON_ARRAY = "[]";
    /**  {@code JSON} /?? */
    public static final String DEFAULT_DATE_PATTERN = "yyyy-MM-dd HH:mm:ss SSS";
    /** {@code Google Gson}  {@literal @Since} ?? - {@code 1.0} */
    public static final Double SINCE_VERSION_10 = 1.0d;
    /** {@code Google Gson}  {@literal @Since} ?? - {@code 1.1} */
    public static final Double SINCE_VERSION_11 = 1.1d;
    /** {@code Google Gson}  {@literal @Since} ?? - {@code 1.2} */
    public static final Double SINCE_VERSION_12 = 1.2d;

    private JSONUtil() {

    }

    /**
     * json??map
     * 
     * @param strJSON
     * @return map
     */
    @SuppressWarnings("unchecked")
    public static Map<String, Object> parseJSON2MapFirstLevel(String strJSON) {
        if (strJSON != null && isJSONObject(strJSON))
            try {
                return (Map<String, Object>) __parseJSON(new JSONObject(strJSON), false);
            } catch (JSONException e) {
                return new HashMap<String, Object>();
            }
        else
            return new HashMap<String, Object>();
    }

    /**
     * json??map
     * 
     * @param strJSON
     * @return map
     */
    @SuppressWarnings("unchecked")
    public static Map<String, Object> parseJSON2Map(String strJSON) {
        if (strJSON != null && isJSONObject(strJSON))
            try {
                return (Map<String, Object>) __parseJSON(new JSONObject(strJSON), true);
            } catch (JSONException e) {
                return new HashMap<String, Object>();
            }
        else
            return new HashMap<String, Object>();
    }

    /**
     * json??list
     * 
     * @param strJSON
     * @return list
     */
    @SuppressWarnings("unchecked")
    public static List<Object> parseJSON2List(String strJSON) {
        if (strJSON != null && isJSONArray(strJSON))
            try {
                return (List<Object>) __parseJSON(new JSONArray(strJSON), true);
            } catch (JSONException e) {
                return new ArrayList<Object>();
            }
        else
            return new ArrayList<Object>();
    }

    /**
     * JSON??JAVAMap,List
     * 
     * @param strJSON
     *            ?{a:'',b:''}['a','b']
     * @return JSON
     * @throws JSONException
     */
    public static Object parseJSON(String strJSON) {
        Object obj = null;
        if (strJSON != null && isJSONArray(strJSON)) {
            obj = parseJSON2List(strJSON);
        } else if (strJSON != null && isJSONObject(strJSON)) {
            obj = parseJSON2Map(strJSON);
        }
        return obj;
    }

    private static Object __parseJSON(Object jsonObj, boolean doAll) throws JSONException {
        Object ret = null;
        if (jsonObj instanceof JSONArray) {
            JSONArray _array = (JSONArray) jsonObj;
            ArrayList<Object> _ret_list = new ArrayList<Object>();
            for (int _i = 0; _i < _array.length(); _i++) {
                Object _item = _array.get(_i);
                if (doAll) {
                    if (_item instanceof JSONObject || _item instanceof JSONArray)
                        _ret_list.add(__parseJSON(_item, true));
                    else
                        _ret_list.add(_item);
                } else {
                    _ret_list.add(_item.toString());
                }
            }
            ret = _ret_list;
        } else if (jsonObj instanceof JSONObject) {
            JSONObject _obj = (JSONObject) jsonObj;
            Map<String, Object> _ret_map = new HashMap<String, Object>();
            for (Iterator<?> _it = _obj.keys(); _it.hasNext();) {
                String _key = _it.next().toString();
                Object _item = _obj.get(_key);
                if (doAll) {
                    if (_item instanceof JSONObject || _item instanceof JSONArray)
                        _ret_map.put(_key, __parseJSON(_item, true));
                    else
                        _ret_map.put(_key, _item);
                } else {
                    _ret_map.put(_key, _item.toString());
                }
            }
            ret = _ret_map;
        }
        return ret;
    }

    private static String toJson(Object target, Type targetType, boolean isSerializeNulls, Double version,
            String datePattern, boolean excludesFieldsWithoutExpose) {
        if (target == null)
            return EMPTY_JSON;
        GsonBuilder builder = new GsonBuilder();
        if (isSerializeNulls)
            builder.serializeNulls();
        if (version != null)
            builder.setVersion(version.doubleValue());
        // if (StringUtil.isEmpty(datePattern))
        // datePattern = DEFAULT_DATE_PATTERN;
        builder.setDateFormat(datePattern);
        if (excludesFieldsWithoutExpose)
            builder.excludeFieldsWithoutExposeAnnotation();
        String result = null;
        Gson gson = builder.create();
        try {
            if (targetType != null) {
                result = gson.toJson(target, targetType);
            } else {
                result = gson.toJson(target);
            }
        } catch (Exception ex) {
            if (target instanceof Collection || target instanceof Iterator || target instanceof Enumeration
                    || target.getClass().isArray()) {
                result = EMPTY_JSON_ARRAY;
            } else
                result = EMPTY_JSON;
        }
        return result;
    }

    /**
     * JAVA??JSON
     * 
     * @param obj
     *            JAVA:bean,map,list
     * @return JSON
     */
    public static String parseObject2JSON(Object obj) {
        return toJson(obj, null, true, null, null, false);
    }

    private static boolean isJSONArray(String strJSON) {
        return strJSON.matches("^\\s*\\[.*");
    }

    private static boolean isJSONObject(String strJSON) {
        return strJSON.matches("^\\s*\\{.*");
    }

}