/*
    * 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.hadoop.hbase.codec.prefixtree.encode;
  
  import java.io.OutputStream;
  import java.util.concurrent.BlockingQueue;
  import java.util.concurrent.LinkedBlockingQueue;
  
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  
  @InterfaceAudience.Private
  public class EncoderPoolImpl implements EncoderPool {
  
    private BlockingQueue<PrefixTreeEncoder> unusedEncoders = 
        new LinkedBlockingQueue<PrefixTreeEncoder>();
  
    @Override
    public PrefixTreeEncoder checkOut(OutputStream outputStream, boolean includeMvccVersion) {
      PrefixTreeEncoder encoder = unusedEncoders.poll();
      if (encoder == null) {
        encoder = new PrefixTreeEncoder(outputStream, includeMvccVersion);
      } else {
        encoder.reset(outputStream, includeMvccVersion);
      }
      return encoder;
    }
  
    @Override
    public void checkIn(PrefixTreeEncoder encoder) {
      this.unusedEncoders.add(encoder);
    }
  }