Source code

001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.reef.examples.group.utils.math;
020
021import org.apache.reef.wake.remote.Codec;
022
023import javax.inject.Inject;
024import java.io.*;
025
026/**
027 * Codec for the Vector type Uses Data*Stream.
028 */
029public class VectorCodec implements Codec<Vector> {
030  /**
031   * This class is instantiated by TANG.
032   */
033  @Inject
034  public VectorCodec() {
035    // Intentionally blank
036  }
037
038  @Override
039  public Vector decode(final byte[] data) {
040    final ByteArrayInputStream bais = new ByteArrayInputStream(data);
041    final Vector result;
042    try (DataInputStream dais = new DataInputStream(bais)) {
043      final int size = dais.readInt();
044      result = new DenseVector(size);
045      for (int i = 0; i < size; i++) {
046        result.set(i, dais.readDouble());
047      }
048    } catch (final IOException e) {
049      throw new RuntimeException(e);
050    }
051    return result;
052  }
053
054  @Override
055  public byte[] encode(final Vector vec) {
056    final ByteArrayOutputStream baos = new ByteArrayOutputStream(vec.size()
057        * (Double.SIZE / Byte.SIZE));
058    try (DataOutputStream daos = new DataOutputStream(baos)) {
059      daos.writeInt(vec.size());
060      for (int i = 0; i < vec.size(); i++) {
061        daos.writeDouble(vec.get(i));
062      }
063    } catch (final IOException e) {
064      throw new RuntimeException(e);
065    }
066    return baos.toByteArray();
067  }
068
069}