org.nordapp.web.util.GsonHashMapDeserializer.java Source code

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Here is the source code for org.nordapp.web.util.GsonHashMapDeserializer.java

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package org.nordapp.web.util;

/*
 * #%L
 * NordApp OfficeBase :: Web
 * %%
 * Copyright (C) 2014 - 2015 I.D.S. DialogSysteme GmbH
 * %%
 * 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.
 * #L%
 */

import java.lang.reflect.Type;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.Map;

import com.google.gson.JsonArray;
import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParseException;
import com.google.gson.JsonPrimitive;

/**
 * @author Benny
 * @since 17.01.2014 Stefan, Use java.util.LinkedHashMap to keep insertion order.
 *
 */
public class GsonHashMapDeserializer implements JsonDeserializer<Object> {

    public Object deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context)
            throws JsonParseException {

        if (json.isJsonNull())
            return null;
        else if (json.isJsonPrimitive())
            return handlePrimitive(json.getAsJsonPrimitive());
        else if (json.isJsonArray())
            return handleArray(json.getAsJsonArray(), context);
        else
            return handleObject(json.getAsJsonObject(), context);
    }

    private Object handlePrimitive(JsonPrimitive json) {
        if (json.isBoolean())
            return json.getAsBoolean();
        else if (json.isString())
            return json.getAsString();
        else {
            BigDecimal bigDec = json.getAsBigDecimal();
            if (json.getAsString().indexOf('.') == -1) {
                // Find out if it is an int type
                try {
                    return bigDec.longValue();
                } catch (ArithmeticException e) {
                }
            }
            // Just return it as a double
            return bigDec.doubleValue();
        }
    }

    private Object handleArray(JsonArray json, JsonDeserializationContext context) {
        ArrayList<Object> array = new ArrayList<Object>();
        for (int i = 0; i < json.size(); i++)
            array.add(deserialize(json.get(i), Object.class, context));

        return array;
    }

    private Object handleObject(JsonObject json, JsonDeserializationContext context) {
        Map<String, Object> map = new LinkedHashMap<String, Object>();
        for (Map.Entry<String, JsonElement> entry : json.entrySet()) {
            map.put(entry.getKey(), deserialize(entry.getValue(), Object.class, context));
        }
        return map;
    }
}