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 com.datastax.oss.driver.internal.core.protocol;
  
  import com.datastax.oss.driver.api.core.connection.FrameTooLongException;
  import com.datastax.oss.protocol.internal.Frame;
  import com.datastax.oss.protocol.internal.FrameCodec;
  import io.netty.buffer.ByteBuf;
  import io.netty.channel.ChannelHandler;
  import io.netty.channel.ChannelHandlerContext;
  import io.netty.handler.codec.MessageToMessageEncoder;
  import java.util.List;
  import net.jcip.annotations.ThreadSafe;
  
  @ChannelHandler.Sharable
  @ThreadSafe
  public class FrameEncoder extends MessageToMessageEncoder<Frame> {
  
    private final FrameCodec<ByteBuf> frameCodec;
    private final int maxFrameLength;
  
    public FrameEncoder(FrameCodec<ByteBuf> frameCodec, int maxFrameLength) {
      super(Frame.class);
      this.frameCodec = frameCodec;
      this.maxFrameLength = maxFrameLength;
    }
  
    @Override
    protected void encode(ChannelHandlerContext ctx, Frame frame, List<Object> out) throws Exception {
      ByteBuf buffer = frameCodec.encode(frame);
      int actualLength = buffer.readableBytes();
      if (actualLength > maxFrameLength) {
        throw new FrameTooLongException(
            ctx.channel().remoteAddress(),
            String.format("Outgoing frame length exceeds %d: %d", maxFrameLength, actualLength));
      }
      out.add(buffer);
    }
  }
  