/*
    * Copyright 2012 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:
    *
    *   https://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.netty5.channel;
  
  import static io.netty5.util.internal.ObjectUtil.checkPositive;
  
  /**
   * The {@link RecvBufferAllocator} that always yields the same buffer
   * size prediction.  This predictor ignores the feed back from the I/O thread.
   */
  public class FixedRecvBufferAllocator extends DefaultMaxMessagesRecvBufferAllocator {
  
      private final int bufferSize;
  
      private final class HandleImpl extends MaxMessageHandle {
          private final int bufferSize;
  
          HandleImpl(int bufferSize) {
              this.bufferSize = bufferSize;
          }
  
          @Override
          public int guess() {
              return bufferSize;
          }
      }
  
      /**
       * Creates a new predictor that always returns the same prediction of
       * the specified buffer size.
       */
      public FixedRecvBufferAllocator(int bufferSize) {
          checkPositive(bufferSize, "bufferSize");
          this.bufferSize = bufferSize;
      }
  
      @Override
      public Handle newHandle() {
          return new HandleImpl(bufferSize);
      }
  }