/*
    * 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 io.netty.util.IllegalReferenceCountException;
  import io.netty.util.internal.StringUtil;
  
  /**
   * Default implementation of a {@link ByteBufHolder} that holds it's data in a {@link ByteBuf}.
   *
   */
  public class DefaultByteBufHolder implements ByteBufHolder {
  
      private final ByteBuf data;
  
      public DefaultByteBufHolder(ByteBuf data) {
          if (data == null) {
              throw new NullPointerException("data");
          }
          this.data = data;
      }
  
      @Override
      public ByteBuf content() {
          if (data.refCnt() <= 0) {
              throw new IllegalReferenceCountException(data.refCnt());
          }
          return data;
      }
  
      @Override
      public ByteBufHolder copy() {
          return new DefaultByteBufHolder(data.copy());
      }
  
      @Override
      public ByteBufHolder duplicate() {
          return new DefaultByteBufHolder(data.duplicate());
      }
  
      @Override
      public int refCnt() {
          return data.refCnt();
      }
  
      @Override
      public ByteBufHolder retain() {
          data.retain();
          return this;
      }
  
      @Override
      public ByteBufHolder retain(int increment) {
          data.retain(increment);
          return this;
      }
  
      @Override
      public boolean release() {
          return data.release();
      }
  
      @Override
      public boolean release(int decrement) {
          return data.release(decrement);
      }
  
      /**
       * Return {@link ByteBuf#toString()} without checking the reference count first. This is useful to implement
       * {@link #toString()}.
       */
      protected final String contentToString() {
          return data.toString();
      }
  
      @Override
      public String toString() {
          return StringUtil.simpleClassName(this) + '(' + contentToString() + ')';
      }
  
      @Override
      public boolean equals(Object o) {
          if (this == o) {
              return true;
          }
          if (o instanceof ByteBufHolder) {
             return data.equals(((ByteBufHolder) o).content());
         }
         return false;
     }
 
     @Override
     public int hashCode() {
         return data.hashCode();
     }
 }