/*
    * Copyright 2013 The Netty Project
    *
    * The Netty Project 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 io.netty.buffer;
  
  import java.nio.ByteOrder;
  
  /**
   * A {@link ByteBuf} implementation that wraps another buffer to prevent a user from increasing or decreasing the
   * wrapped buffer's reference count.
   */
  final class UnreleasableByteBuf extends WrappedByteBuf {
  
      private SwappedByteBuf swappedBuf;
  
      UnreleasableByteBuf(ByteBuf buf) {
          super(buf);
      }
  
      @Override
      public ByteBuf order(ByteOrder endianness) {
          if (endianness == null) {
              throw new NullPointerException("endianness");
          }
          if (endianness == order()) {
              return this;
          }
  
          SwappedByteBuf swappedBuf = this.swappedBuf;
          if (swappedBuf == null) {
              this.swappedBuf = swappedBuf = new SwappedByteBuf(this);
          }
          return swappedBuf;
      }
  
      @Override
      public ByteBuf readSlice(int length) {
          return new UnreleasableByteBuf(buf.readSlice(length));
      }
  
      @Override
      public ByteBuf slice() {
          return new UnreleasableByteBuf(buf.slice());
      }
  
      @Override
      public ByteBuf slice(int index, int length) {
          return new UnreleasableByteBuf(buf.slice(index, length));
      }
  
      @Override
      public ByteBuf duplicate() {
          return new UnreleasableByteBuf(buf.duplicate());
      }
  
      @Override
      public ByteBuf retain(int increment) {
          return this;
      }
  
      @Override
      public ByteBuf retain() {
          return this;
      }
  
      @Override
      public boolean release() {
          return false;
      }
  
      @Override
      public boolean release(int decrement) {
          return false;
      }
  }