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.io.storage.util;
020
021import org.apache.reef.exception.evaluator.ServiceException;
022import org.apache.reef.io.Accumulable;
023import org.apache.reef.io.Accumulator;
024import org.apache.reef.io.serialization.Serializer;
025
026import java.io.DataOutputStream;
027import java.io.IOException;
028import java.io.OutputStream;
029import java.nio.charset.StandardCharsets;
030
031public class StringSerializer implements
032    Serializer<String, OutputStream> {
033  @Override
034  public Accumulable<String> create(final OutputStream arg) {
035    final DataOutputStream dos = new DataOutputStream(arg);
036    return new Accumulable<String>() {
037
038      @Override
039      public Accumulator<String> accumulator() throws ServiceException {
040        return new Accumulator<String>() {
041
042          @Override
043          public void add(final String datum) throws ServiceException {
044            final byte[] b = datum.getBytes(StandardCharsets.UTF_8);
045            try {
046              dos.writeInt(b.length);
047              dos.write(b);
048            } catch (final IOException e) {
049              throw new ServiceException(e);
050            }
051
052          }
053
054          @Override
055          public void close() throws ServiceException {
056            try {
057              dos.close();
058            } catch (final IOException e) {
059              throw new ServiceException(e);
060            }
061          }
062        };
063      }
064    };
065  }
066}