content: /*
   * Copyright (c) 2018, 2020, Oracle and/or its affiliates.
   *
   * This program is free software; you can redistribute it and/or modify it under
   * the terms of the GNU General Public License, version 2.0, as published by the
   * Free Software Foundation.
   *
   * This program is also distributed with certain software (including but not
   * limited to OpenSSL) that is licensed under separate terms, as designated in a
   * particular file or component or in included license documentation. The
   * authors of MySQL hereby grant you an additional permission to link the
   * program and your derivative works with the separately licensed software that
   * they have included with MySQL.
   *
   * Without limiting anything contained in the foregoing, this file, which is
   * part of MySQL Connector/J, is also subject to the Universal FOSS Exception,
   * version 1.0, a copy of which can be found at
   * http://oss.oracle.com/licenses/universal-foss-exception.
   *
   * This program is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
   * FOR A PARTICULAR PURPOSE. See the GNU General Public License, version 2.0,
   * for more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
   */
  
  package com.mysql.cj.protocol.x;
  
  import java.nio.ByteBuffer;
  import java.nio.ByteOrder;
  
  import com.mysql.cj.protocol.MessageHeader;
  
  public class XMessageHeader implements MessageHeader {
      public static final int MESSAGE_SIZE_LENGTH = 4;
      public static final int MESSAGE_TYPE_LENGTH = 1;
      public static final int HEADER_LENGTH = MESSAGE_SIZE_LENGTH + MESSAGE_TYPE_LENGTH;
  
      private ByteBuffer headerBuf;
      /** Type tag of the message to read (indicates parser to use). */
      private int messageType = -1;
      /** Size of the message that will be read. */
      private int messageSize = -1;
  
      public XMessageHeader() {
          this.headerBuf = ByteBuffer.allocate(HEADER_LENGTH).order(ByteOrder.LITTLE_ENDIAN);
      }
  
      public XMessageHeader(byte[] buf) {
          this.headerBuf = ByteBuffer.wrap(buf).order(ByteOrder.LITTLE_ENDIAN);
      }
  
      private void parseBuffer() {
          if (this.messageSize == -1) {
              this.headerBuf.position(0); // process the completed header and initiate message reading
              this.messageSize = this.headerBuf.getInt() - 1;
              this.messageType = this.headerBuf.get();
          }
      }
  
      @Override
      public ByteBuffer getBuffer() {
          return this.headerBuf;
      }
  
      @Override
      public int getMessageSize() {
          parseBuffer();
          return this.messageSize;
      }
  
      @Override
      public byte getMessageSequence() {
          return 0;
      }
  
      public int getMessageType() {
          parseBuffer();
          return this.messageType;
      }
  }
  