hbase-common/src/main/java/org/apache/hadoop/hbase/codec/Codec.java

   1 /**
   2  * Licensed to the Apache Software Foundation (ASF) under one
   3  * or more contributor license agreements.  See the NOTICE file
   4  * distributed with this work for additional information
   5  * regarding copyright ownership.  The ASF licenses this file
   6  * to you under the Apache License, Version 2.0 (the
   7  * "License"); you may not use this file except in compliance
   8  * with the License.  You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  */
  18 package org.apache.hadoop.hbase.codec;
  19
  20 import java.io.InputStream;
  21 import java.io.OutputStream;
  22
  23 import org.apache.hadoop.hbase.CellScanner;
  24 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
  25 import org.apache.hadoop.hbase.io.CellOutputStream;
  26 import org.apache.hadoop.hbase.nio.ByteBuff;
  27 import org.apache.yetus.audience.InterfaceAudience;
  28
  29 /**
  30  * Encoder/Decoder for Cell.
  31  *
  32  * <p>Like {@link org.apache.hadoop.hbase.io.encoding.DataBlockEncoder}
  33  * only Cell-based rather than KeyValue version 1 based
  34  * and without presuming an hfile context.  Intent is an Interface that will work for hfile and
  35  * rpc.
  36  */
  37 @InterfaceAudience.LimitedPrivate({HBaseInterfaceAudience.COPROC, HBaseInterfaceAudience.PHOENIX})
  38 public interface Codec {
  39   // TODO: interfacing with {@link org.apache.hadoop.hbase.io.encoding.DataBlockEncoder}
  40   /**
  41    * Call flush when done.  Some encoders may not put anything on the stream until flush is called.
  42    * On flush, let go of any resources used by the encoder.
  43    */
  44   interface Encoder extends CellOutputStream {}
  45
  46   /**
  47    * Implementations should implicitly clean up any resources allocated when the
  48    * Decoder/CellScanner runs off the end of the cell block. Do this rather than require the user
  49    * call close explicitly.
  50    */
  51   interface Decoder extends CellScanner {}
  52
  53   Decoder getDecoder(InputStream is);
  54   Decoder getDecoder(ByteBuff buf);
  55   Encoder getEncoder(OutputStream os);
  56 }