content: /*
   * 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.cassandra.io.compress;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.util.Collections;
  import java.util.Map;
  import java.util.Set;
  
  /**
   * A Compressor which doesn't actually compress any data. This is useful for either non-compressible data
   * (typically already compressed or encrypted) that you still want block checksums for or for fast writing.
   * Some relevant tickets:
   * <p>
   *     <ul>
   *         <li>CASSANDRA-12682: Non compressed SSTables can silently corrupt data</li>
   *         <li>CASSANDRA-9264: Non compressed SSTables are written without checksums</li>
   *     </ul>
   * </p>
   */
  public class NoopCompressor implements ICompressor
  {
      public static NoopCompressor create(Map<String, String> ignored)
      {
          return new NoopCompressor();
      }
  
      public int initialCompressedBufferLength(int chunkLength)
      {
          return chunkLength;
      }
  
      public int uncompress(byte[] input, int inputOffset, int inputLength, byte[] output, int outputOffset) throws IOException
      {
          System.arraycopy(input, inputOffset, output, outputOffset, inputLength);
          return inputLength;
      }
  
      public void compress(ByteBuffer input, ByteBuffer output) throws IOException
      {
          output.put(input);
      }
  
      public void uncompress(ByteBuffer input, ByteBuffer output) throws IOException
      {
          output.put(input);
      }
  
      public BufferType preferredBufferType()
      {
          return BufferType.ON_HEAP;
      }
  
      public boolean supports(BufferType bufferType)
      {
          return true;
      }
  
      public Set<String> supportedOptions()
      {
          return Collections.emptySet();
      }
  }
  