/*
    * Copyright 2024 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.netty.channel.nio;
  
  
  import io.netty.channel.IoEvent;
  import io.netty.channel.IoHandle;
  import io.netty.channel.IoRegistration;
  import io.netty.util.internal.ObjectUtil;
  
  import java.nio.channels.SelectableChannel;
  import java.nio.channels.SelectionKey;
  
  /**
   * Allows to create an {@link IoHandle} for a {@link SelectableChannel}, not necessarily created by Netty. This
   * {@link IoHandle} can be used together with {@link NioIoHandler} and so have events dispatched for
   * the {@link SelectableChannel}.
   */
  public abstract class NioSelectableChannelIoHandle<S extends SelectableChannel> implements IoHandle, NioIoHandle {
      private final S channel;
  
      public NioSelectableChannelIoHandle(S channel) {
          this.channel = ObjectUtil.checkNotNull(channel, "channel");
      }
  
      @Override
      public void handle(IoRegistration registration, IoEvent ioEvent) {
          SelectionKey key = ((NioIoRegistration) registration).selectionKey();
          NioSelectableChannelIoHandle.this.handle(channel, key);
      }
  
      @Override
      public void close() throws Exception {
          channel.close();
      }
  
      @Override
      public SelectableChannel selectableChannel() {
          return channel;
      }
  
      protected abstract void handle(S channel, SelectionKey key);
  
      protected void deregister(S channel) {
          // NOOP.
      }
  }