org.apache.mahout.math.JsonVectorAdapter.java Source code

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Here is the source code for org.apache.mahout.math.JsonVectorAdapter.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */
package org.apache.mahout.math;

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

import java.lang.reflect.Type;

public class JsonVectorAdapter implements JsonSerializer<Vector>, JsonDeserializer<Vector> {

    public static final String VECTOR = "vector";

    public JsonElement serialize(Vector src, Type typeOfSrc, JsonSerializationContext context) {
        GsonBuilder builder = new GsonBuilder();
        builder.registerTypeAdapter(Vector.class, new JsonVectorAdapter());
        Gson gson = builder.create();
        JsonObject obj = new JsonObject();
        obj.add(JsonMatrixAdapter.CLASS, new JsonPrimitive(src.getClass().getName()));
        obj.add(VECTOR, new JsonPrimitive(gson.toJson(src)));
        return obj;
    }

    public Vector deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) {
        GsonBuilder builder = new GsonBuilder();
        builder.registerTypeAdapter(Vector.class, new JsonVectorAdapter());
        Gson gson = builder.create();
        JsonObject obj = json.getAsJsonObject();
        String klass = obj.get(JsonMatrixAdapter.CLASS).getAsString();
        String vector = obj.get(VECTOR).getAsString();
        ClassLoader ccl = Thread.currentThread().getContextClassLoader();
        Class<?> cl;
        try {
            cl = ccl.loadClass(klass);
        } catch (ClassNotFoundException e) {
            throw new JsonParseException(e);
        }
        return (Vector) gson.fromJson(vector, cl);
    }

}