Sync.java

/*
 * Copyright 2014-2016 CyberVision, Inc.
 *
 * Licensed 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.kaaproject.kaa.common.channels.protocols.kaatcp.messages;

import org.kaaproject.kaa.common.channels.protocols.kaatcp.KaaTcpProtocolException;


/**
 * Sync message Class.
 * The SYNC message is used as intermediate class for decoding messages
 * SyncRequest,SyncResponse
 *
 * @author Andrey Panasenko
 *
 *         Sync message extend KaaSync with  Payload Avro object.
 *
 *         Payload Avro object depend on Flags object can be zipped and than encrypted with AES
 *         SessionKey exchanged with the CONNECT message.
 */
public class Sync extends KaaSync {

  /**
   * Avro object byte representation.
   */
  private byte[] avroObject;


  /**
   * Constructor for migrating from KaaSync to specific SyncRequest or SyncResponse.
   *
   * @param old KaaSync object which used to create new
   */
  protected Sync(KaaSync old) {
    super(old);
    setKaaSyncMessageType(KaaSyncMessageType.SYNC);
  }

  /**
   * Default constructor.
   *
   * @param isRequest  boolean 'true' SyncRequest, else SyncResponse
   * @param avroObject byte[] byte array of Avro object
   * @param isZipped   boolean 'true' if Avro object is should be zipped
   * @param isEcrypted boolean 'true' if Avro object is Encrypted
   */
  public Sync(boolean isRequest, byte[] avroObject, boolean isZipped, boolean isEcrypted) {
    super(isRequest, isZipped, isEcrypted);
    setAvroObject(avroObject);
    setKaaSyncMessageType(KaaSyncMessageType.SYNC);
  }

  /**
   * Default constructor.
   */
  public Sync() {
    setKaaSyncMessageType(KaaSyncMessageType.SYNC);
  }

  /**
   * Decode Avro Object.
   */
  protected void decodeAvroObject() {
    int avroObjectSize = buffer.capacity() - buffer.position();
    if (avroObjectSize > 0) {
      avroObject = new byte[avroObjectSize];
      buffer.get(avroObject);
    }
  }

  /* (non-Javadoc)
   * @see org.kaaproject.kaa.common.channels.protocols.kaatcp.messages.mqttFrame#pack(int)
   */
  @Override
  protected void pack() {
    packVeriableHeader();
    buffer.put(getAvroObject());
  }

  /* (non-Javadoc)
   * @see org.kaaproject.kaa.common.channels.protocols.kaatcp.messages.mqttFrame#decode()
   */
  @Override
  protected void decode() throws KaaTcpProtocolException {
    decodeVariableHeader();
    decodeAvroObject();
  }


  /**
   * Avro Object (SyncRequest/SyncResponse) getter.
   *
   * @return byte[] avroObject
   */
  public byte[] getAvroObject() {
    return avroObject;
  }

  /**
   * Avro Object (SyncRequest/SyncResponse) setter.
   *
   * @param avroObject byte[] byte array of Avro object
   */
  public void setAvroObject(byte[] avroObject) {
    this.avroObject = avroObject;
    remainingLength = KAASYNC_VERIABLE_HEADER_LENGTH_V1 + avroObject.length;
  }
}