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.sidecar.client;
  
  import java.nio.ByteBuffer;
  
  /**
   * A generic wrapper around bytes to allow for on/off-heap byte arrays.
   */
  public interface StreamBuffer
  {
      /**
       * Copies bytes from this {@link StreamBuffer} into the {@link ByteBuffer destination}
       *
       * @param sourceOffset the offset within the {@link StreamBuffer} to be read; must be non-negative and
       *                     larger than the buffer length
       * @param destination  a {@link ByteBuffer} where the data will be copied
       * @param length       the number of bytes to be copied from the {@link StreamBuffer}; must be non-negative and
       *                     larger than the {@code buffer.length - sourceOffset}
       */
      void copyBytes(int sourceOffset, ByteBuffer destination, int length);
  
      /**
       * Copies bytes from this {@link StreamBuffer} into the byte array {@code destination}.
       *
       * @param sourceOffset     the offset within the {@link StreamBuffer} to be read; must be non-negative and
       *                         larger than the buffer length
       * @param destination      the target byte array where the source bytes will be copied
       * @param destinationIndex the offset in the {@code destination} where to start writing data
       * @param length           the number of bytes to be copied from the {@link StreamBuffer}; must be non-negative and
       *                         larger than the {@code buffer.length - sourceOffset}
       */
      void copyBytes(int sourceOffset, byte[] destination, int destinationIndex, int length);
  
      /**
       * Returns a byte from the given {@code index}.
       *
       * @param index the index in the array; must be non-negative and within the bounds of the {@link StreamBuffer}
       * @return a byte from the given {@code index}
       */
      byte getByte(int index);
  
      /**
       * @return the number of readable bytes from this {@link StreamBuffer}
       */
      int readableBytes();
  
      /**
       * Release the underlying buffer
       */
      void release();
  
      /**
       * Wraps a byte array into a {@link ByteArrayWrapper}
       *
       * @param bytes the underlying byte array
       * @return the object wrapping byte array
       */
      static ByteArrayWrapper wrap(byte[] bytes)
      {
          return new ByteArrayWrapper(bytes);
      }
  
      /**
       * A {@link StreamBuffer} implementation that wraps a byte array
       */
      class ByteArrayWrapper implements StreamBuffer
      {
          private final byte[] bytes;
  
          private ByteArrayWrapper(byte[] bytes)
          {
              this.bytes = bytes;
          }
  
          @Override
          public void copyBytes(int sourceOffset, ByteBuffer destination, int length)
          {
              destination.put(bytes, sourceOffset, length);
              destination.flip();
          }
  
          @Override
          public void copyBytes(int sourceOffset, byte[] destination, int destinationIndex, int length)
          {
              System.arraycopy(bytes, sourceOffset, destination, destinationIndex, length);
          }
  
          @Override
          public byte getByte(int index)
          {
              return bytes[index];
          }
  
          @Override
          public int readableBytes()
          {
              return bytes.length;
          }
  
          @Override
          public void release()
          {
          }
      }
  }
  