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 org.apache.camel.component.hl7;
  
  import java.io.ByteArrayOutputStream;
  
  import ca.uhn.hl7v2.model.Message;
  import io.netty.buffer.ByteBuf;
  import io.netty.channel.ChannelHandlerContext;
  import io.netty.handler.codec.MessageToByteEncoder;
  import org.apache.camel.StreamCache;
  
  /**
   * HL7 MLLP Encoder for Netty
   */
  class HL7MLLPNettyEncoder extends MessageToByteEncoder<Object> {
  
      private final HL7MLLPConfig config;
  
      HL7MLLPNettyEncoder() {
          this(new HL7MLLPConfig());
      }
  
      HL7MLLPNettyEncoder(HL7MLLPConfig config) {
          this.config = config;
      }
  
      @Override
      protected void encode(ChannelHandlerContext channelHandlerContext, Object message, ByteBuf byteBuf) throws Exception {
          if (message == null) {
              throw new IllegalArgumentException("Message to be encoded is null");
          } else if (message instanceof Exception) {
              // we cannot handle exceptions
              throw (Exception) message;
          }
  
          byte[] body;
          if (message instanceof StreamCache) {
              // need to convert to byte array for the encoder
              StreamCache sc = (StreamCache) message;
              ByteArrayOutputStream bos = new ByteArrayOutputStream();
              sc.writeTo(bos);
              body = bos.toByteArray();
          } else if (message instanceof Message) {
              body = ((Message) message).encode().getBytes(config.getCharset());
          } else if (message instanceof String) {
              body = ((String) message).getBytes(config.getCharset());
          } else if (message instanceof byte[]) {
              body = (byte[]) message;
          } else {
              throw new IllegalArgumentException(
                      "The message to encode is not a supported type: "
                                                 + message.getClass().getCanonicalName());
          }
          byteBuf.writeByte(config.getStartByte());
          byteBuf.writeBytes(body);
          byteBuf.writeByte(config.getEndByte1());
          byteBuf.writeByte(config.getEndByte2());
      }
  }
  