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 io.jafka.network;
  
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.nio.channels.GatheringByteChannel;
  
  import io.jafka.common.ErrorMapping;
  import io.jafka.message.MessageSet;
  
  /**
   * A zero-copy message response that writes the bytes needed directly from
   * the file wholly in kernel space
   * 
   * @author adyliu (imxylz@gmail.com)
   * @since 1.0
   */
  public class MessageSetSend extends AbstractSend {
  
      private long sent = 0;
  
      private long size;
  
      private final ByteBuffer header = ByteBuffer.allocate(6);
  
      //
      public final MessageSet messages;
  
      public final ErrorMapping errorCode;
  
      public MessageSetSend(MessageSet messages, ErrorMapping errorCode) {
          super();
          this.messages = messages;
          this.errorCode = errorCode;
          this.size = messages.getSizeInBytes();
          header.putInt((int) (size + 2));
          header.putShort(errorCode.code);
          header.rewind();
      }
  
      public MessageSetSend(MessageSet messages) {
          this(messages, ErrorMapping.NoError);
      }
  
      public MessageSetSend() {
          this(MessageSet.Empty);
      }
  
      public int writeTo(GatheringByteChannel channel) throws IOException {
          expectIncomplete();
          int written = 0;
          if (header.hasRemaining()) {
              written += channel.write(header);
          }
          if (!header.hasRemaining()) {
              int fileBytesSent = (int) messages.writeTo(channel, sent, size - sent);
              written += fileBytesSent;
              sent += fileBytesSent;
          }
          if (sent >= size) {
              setCompleted();
          }
          return written;
      }
  
      public int getSendSize() {
          return (int) size + header.capacity();
      }
  
  }
  