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.util;
  
  import java.nio.ByteBuffer;
  
  /**
   * This is the same as DataInputBuffer, i.e. a stream for a fixed byte buffer,
   * except that we also implement FileDataInput by using an offset and a file path.
   */
  public class FileSegmentInputStream extends DataInputBuffer implements FileDataInput
  {
      private final String filePath;
      private final long offset;
  
      public FileSegmentInputStream(ByteBuffer buffer, String filePath, long offset)
      {
          super(buffer, false);
          this.filePath = filePath;
          this.offset = offset;
      }
  
      public String getPath()
      {
          return filePath;
      }
  
      private long size()
      {
          return offset + buffer.capacity();
      }
  
      public boolean isEOF()
      {
          return !buffer.hasRemaining();
      }
  
      public long bytesRemaining()
      {
          return buffer.remaining();
      }
  
      public void seek(long pos)
      {
          if (pos < 0 || pos > size())
              throw new IllegalArgumentException(String.format("Unable to seek to position %d in %s (%d bytes) in partial mode",
                                                               pos,
                                                               getPath(),
                                                               size()));
  
  
          buffer.position((int) (pos - offset));
      }
  
      @Override
      public boolean markSupported()
      {
          return false;
      }
  
      public DataPosition mark()
      {
          throw new UnsupportedOperationException();
      }
  
      public void reset(DataPosition mark)
      {
          throw new UnsupportedOperationException();
      }
  
      public long bytesPastMark(DataPosition mark)
      {
          return 0;
      }
  
      public long getFilePointer()
      {
          return offset + buffer.position();
      }
  }
  