| /** |
| * 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.io.erasurecode.rawcoder; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.conf.Configurable; |
| |
| /** |
| * RawErasureCoder is a common interface for {@link RawErasureEncoder} and |
| * {@link RawErasureDecoder} as both encoder and decoder share some properties. |
| * |
| * RawErasureCoder is part of ErasureCodec framework, where ErasureCoder is |
| * used to encode/decode a group of blocks (BlockGroup) according to the codec |
| * specific BlockGroup layout and logic. An ErasureCoder extracts chunks of |
| * data from the blocks and can employ various low level RawErasureCoders to |
| * perform encoding/decoding against the chunks. |
| * |
| * To distinguish from ErasureCoder, here RawErasureCoder is used to mean the |
| * low level constructs, since it only takes care of the math calculation with |
| * a group of byte buffers. |
| */ |
| @InterfaceAudience.Private |
| public interface RawErasureCoder extends Configurable { |
| |
| /** |
| * Get a coder option value. |
| * @param option |
| * @return |
| */ |
| public Object getCoderOption(CoderOption option); |
| |
| /** |
| * Set a coder option value. |
| * @param option |
| * @param value |
| */ |
| public void setCoderOption(CoderOption option, Object value); |
| |
| /** |
| * The number of data input units for the coding. A unit can be a byte, |
| * chunk or buffer or even a block. |
| * @return count of data input units |
| */ |
| public int getNumDataUnits(); |
| |
| /** |
| * The number of parity output units for the coding. A unit can be a byte, |
| * chunk, buffer or even a block. |
| * @return count of parity output units |
| */ |
| public int getNumParityUnits(); |
| |
| /** |
| * Should be called when release this coder. Good chance to release encoding |
| * or decoding buffers |
| */ |
| public void release(); |
| } |