com.commonslibrary.commons.utils.JsonUtils.java Source code

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Here is the source code for com.commonslibrary.commons.utils.JsonUtils.java

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/*******************************************************************************
 *
 * Copyright (c) 2016 Mickael Gizthon . All rights reserved. Email:2013mzhou@gmail.com
 *
 * 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.
 ******************************************************************************/

package com.commonslibrary.commons.utils;

import com.google.gson.Gson;
import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;

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

public class JsonUtils {
    private JsonUtils() {
        throw new UnsupportedOperationException("cannot be instantiated");
    }

    /**
     * ?JsonObject
     *
     * @param json
     * @return
     */
    public static JsonObject parseJson(String json) {
        try {
            JsonParser parser = new JsonParser();
            JsonObject jsonObj = parser.parse(json).getAsJsonObject();
            return jsonObj;
        } catch (Exception e) {
            return null;
        }
    }

    /**
     * ?jsonMap
     *
     * @param json
     * @return
     */
    public static Map<String, Object> toMap(String json) {
        return toMap(parseJson(json));
    }

    /**
     * JSONObjec??Map-List?
     *
     * @param json
     * @return
     */
    public static Map<String, Object> toMap(JsonObject json) {
        Map<String, Object> map = new HashMap<String, Object>();
        Set<Map.Entry<String, JsonElement>> entrySet = json.entrySet();
        for (Iterator<Map.Entry<String, JsonElement>> iter = entrySet.iterator(); iter.hasNext();) {
            Map.Entry<String, JsonElement> entry = iter.next();
            String key = entry.getKey();
            Object value = entry.getValue();
            if (value instanceof JsonArray)
                map.put((String) key, toList((JsonArray) value));
            else if (value instanceof JsonObject)
                map.put((String) key, toMap((JsonObject) value));
            else
                map.put((String) key, value);
        }
        return map;
    }

    /**
     * JSONArray??List?
     *
     * @param json
     * @return
     */
    public static List<Object> toList(JsonArray json) {
        List<Object> list = new ArrayList<Object>();
        if (json == null) {
            return list;
        }
        for (int i = 0; i < json.size(); i++) {
            Object value = json.get(i);
            if (value instanceof JsonArray) {
                list.add(toList((JsonArray) value));
            } else if (value instanceof JsonObject) {
                list.add(toMap((JsonObject) value));
            } else {
                list.add(value);
            }
        }
        return list;
    }

    public static String mapToString(Map map) {
        try {
            return new Gson().toJson(map);
        } catch (Exception e) {
            return "";
        }
    }

    /**
     * ??json
     *
     * @param obj
     * @return
     */
    public static String toJson(Object obj) {
        try {
            Gson gson = new Gson();
            return gson.toJson(obj);
        } catch (Exception e) {
            return "";
        }
    }

}