/*
    * 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.giraph.utils.io;
  
  import org.apache.giraph.utils.ExtendedDataInput;
  import org.apache.giraph.utils.Factory;
  import org.apache.hadoop.io.Writable;
  
  import java.io.DataOutput;
  
  /**
   * Provides both DataOutput which we can write to and DataInputs which are
   * going to read data which was written to DataOutput.
   */
  public abstract class DataInputOutput implements
      Writable, Factory<ExtendedDataInput> {
    /**
     * Get DataOutput to write to
     *
     * @return DataOutput which we can write to
     */
    public abstract DataOutput getDataOutput();
  
    /**
     * Create DataInput which reads data from underlying DataOutput
     *
     * @return DataInput
     */
    public abstract ExtendedDataInput createDataInput();
  
    @Override
    public ExtendedDataInput create() {
      return createDataInput();
    }
  }