I have a class in which I am passing certain parameters through the constructor and then using those parameters to make one final byte array with a proper format (header + data) as shown below and it works fine:

How should I design this Frame class so that it can take all the parameters to make one packedByteArray (through the constructor I am doing right now) and also it should be able to take byteArray parameter as well and give me all other fields by deserializing this? just like I am doing for locationFrom field.

I am mainly trying to see how I can design my class so that if I asks for individual fields value given a byteArray, it should be able to give me those values back. Also it should be able to serialize everything into one byteArray given all the fields?

I have a class in which I am passing certain parameters through the constructor and then using those parameters to make one final byte array with a proper format (header + data) and it works fine:

How should I design this Frame class so that it can take all the parameters to make one packedByteArray (through the constructor I am doing right now) and also it should be able to take byteArray parameter as well and give me all other fields by deserializing this? Just like I am doing for locationFrom field.

I am mainly trying to see how I can design my class so that if I asks for individual fields value given a byteArray, it should be able to give me those values back. Also, it should be able to serialize everything into one byteArray given all the fields.

public final class Frame {
  private final byte addressedCenter;
  private final byte version;
  private final Map<byte[], byte[]> keyDataHolder;
  private final long location;
  private final long locationFrom;
  private final long locationOrigin;
  private final byte partition;
  private final byte copy;

  public Frame(byte addressedCenter, byte version,
      Map<byte[], byte[]> keyDataHolder, long location, long locationFrom,
      long locationOrigin, byte partition, byte copy) {
    this.addressedCenter = addressedCenter;
    this.version = version;
    this.keyDataHolder = keyDataHolder;
    this.location = location;
    this.locationFrom = locationFrom;
    this.locationOrigin = locationOrigin;
    this.partition = partition;
    this.copy = copy;
  }

  public byte[] serialize() {
    ByteBuffer byteBuffer = ByteBuffer.allocate(getBufferUsed(keyDataHolder)).order(ByteOrder.BIG_ENDIAN);

    // header layout
    byteBuffer.put(addressedCenter).put(version).putInt(keyDataHolder.size())
        .putInt(getBufferUsed(keyDataHolder)).putLong(location).putLong(locationFrom)
        .putLong(locationOrigin).put(partition).put(copy);

    // now the data layout
    for (Map.Entry<byte[], byte[]> entry : keyDataHolder.entrySet()) {
      byte keyType = 0;
      byte[] key = entry.getKey();
      byte[] value = entry.getValue();
      byte keyLength = (byte) key.length;
      short valueLength = (short) value.length;

      ByteBuffer dataBuffer = ByteBuffer.wrap(value);
      long timestamp = valueLength > 10 ? dataBuffer.getLong(2) : System.currentTimeMillis();

      byteBuffer.put(keyType).put(keyLength).put(key).putLong(timestamp).putShort(valueLength)
          .put(value);
    }

    return byteBuffer.array();
  }
  
  // this method is returning only `locationFrom`
  public static long getLocationFrom(final byte[] byteArray) {
    ByteBuffer bb = ByteBuffer.wrap(byteArray).order(ByteOrder.BIG_ENDIAN);
    bb.rewind();

    byte addressedCenter = bb.get();
    byte version = bb.get();
    int numOfRecords = bb.getInt();
    int bufferUsed = bb.getInt();
    long location = bb.getLong();
    long locationFrom = bb.getLong();
    long locationOrigin = bb.getLong();
    byte partition = bb.get();
    byte copy = bb.get();

    byte keyType = bb.get();
    byte keyLength = bb.get();
    byte[] extractKeyValue = new byte[keyLength];
    bb.get(extractKeyValue);
    String key = new String(extractKeyValue, StandardCharsets.UTF_8);
    long timestamp = bb.getLong();
    short dataSize = bb.getShort();

    if (dataSize >= 16) {
      location = bb.getLong();
      locationFrom = bb.getLong();
    } else {
        // log that we have different size and we cannot extract
        // location and locationFrom it.
    }
    return locationFrom;
  } 
  
  // this method is returning only `locationFrom`
  public static long getLocation(final byte[] byteArray) {
    ByteBuffer bb = ByteBuffer.wrap(byteArray).order(ByteOrder.BIG_ENDIAN);
    bb.rewind();

    byte addressedCenter = bb.get();
    byte version = bb.get();
    int numOfRecords = bb.getInt();
    int bufferUsed = bb.getInt();
    long location = bb.getLong();
    long locationFrom = bb.getLong();
    long locationOrigin = bb.getLong();
    byte partition = bb.get();
    byte copy = bb.get();

    byte keyType = bb.get();
    byte keyLength = bb.get();
    byte[] extractKeyValue = new byte[keyLength];
    bb.get(extractKeyValue);
    String key = new String(extractKeyValue, StandardCharsets.UTF_8);
    long timestamp = bb.getLong();
    short dataSize = bb.getShort();

    if (dataSize >= 16) {
      location = bb.getLong();
      locationFrom = bb.getLong();
    } else {
        // log that we have different size and we cannot extract
        // location and locationFrom it.
    }
    return location;
  }       
  
  // 36 + dataSize + 1 + 1 + keyLength + 8 + 2;
  private int getBufferUsed(final Map<byte[], byte[]> keyDataHolder) {
    int size = 36;
    for (Map.Entry<byte[], byte[]> entry : keyDataHolder.entrySet()) {
      size += 1 + 1 + 8 + 2;
      size += entry.getKey().length;
      size += entry.getValue().length;
    }
    return size;
  }  
}

public final class Frame {
  private final byte addressedCenter;
  private final byte version;
  private final Map<byte[], byte[]> keyDataHolder;
  private final long location;
  private final long locationFrom;
  private final long locationOrigin;
  private final byte partition;
  private final byte copy;

  public Frame(byte addressedCenter, byte version,
      Map<byte[], byte[]> keyDataHolder, long location, long locationFrom,
      long locationOrigin, byte partition, byte copy) {
    this.addressedCenter = addressedCenter;
    this.version = version;
    this.keyDataHolder = keyDataHolder;
    this.location = location;
    this.locationFrom = locationFrom;
    this.locationOrigin = locationOrigin;
    this.partition = partition;
    this.copy = copy;
  }

  public byte[] serialize() {
    ByteBuffer byteBuffer = ByteBuffer.allocate(getBufferUsed(keyDataHolder)).order(ByteOrder.BIG_ENDIAN);

    // header layout
    byteBuffer.put(addressedCenter).put(version).putInt(keyDataHolder.size())
        .putInt(getBufferUsed(keyDataHolder)).putLong(location).putLong(locationFrom)
        .putLong(locationOrigin).put(partition).put(copy);

    // now the data layout
    for (Map.Entry<byte[], byte[]> entry : keyDataHolder.entrySet()) {
      byte keyType = 0;
      byte[] key = entry.getKey();
      byte[] value = entry.getValue();
      byte keyLength = (byte) key.length;
      short valueLength = (short) value.length;

      ByteBuffer dataBuffer = ByteBuffer.wrap(value);
      long timestamp = valueLength > 10 ? dataBuffer.getLong(2) : System.currentTimeMillis();

      byteBuffer.put(keyType).put(keyLength).put(key).putLong(timestamp).putShort(valueLength)
          .put(value);
    }

    return byteBuffer.array();
  }
  
  // this method is returning only `locationFrom`
  public static long getLocationFrom(final byte[] byteArray) {
    ByteBuffer bb = ByteBuffer.wrap(byteArray).order(ByteOrder.BIG_ENDIAN);
    bb.rewind();

    byte addressedCenter = bb.get();
    byte version = bb.get();
    int numOfRecords = bb.getInt();
    int bufferUsed = bb.getInt();
    long location = bb.getLong();
    long locationFrom = bb.getLong();
    long locationOrigin = bb.getLong();
    byte partition = bb.get();
    byte copy = bb.get();

    byte keyType = bb.get();
    byte keyLength = bb.get();
    byte[] extractKeyValue = new byte[keyLength];
    bb.get(extractKeyValue);
    String key = new String(extractKeyValue, StandardCharsets.UTF_8);
    long timestamp = bb.getLong();
    short dataSize = bb.getShort();

    if (dataSize >= 16) {
      location = bb.getLong();
      locationFrom = bb.getLong();
    } else {
        // log that we have different size and we cannot extract
        // location and locationFrom it.
    }
    return locationFrom;
  } 
  
  // this method is returning only `location`
  public static long getLocation(final byte[] byteArray) {
    ByteBuffer bb = ByteBuffer.wrap(byteArray).order(ByteOrder.BIG_ENDIAN);
    bb.rewind();

    byte addressedCenter = bb.get();
    byte version = bb.get();
    int numOfRecords = bb.getInt();
    int bufferUsed = bb.getInt();
    long location = bb.getLong();
    long locationFrom = bb.getLong();
    long locationOrigin = bb.getLong();
    byte partition = bb.get();
    byte copy = bb.get();

    byte keyType = bb.get();
    byte keyLength = bb.get();
    byte[] extractKeyValue = new byte[keyLength];
    bb.get(extractKeyValue);
    String key = new String(extractKeyValue, StandardCharsets.UTF_8);
    long timestamp = bb.getLong();
    short dataSize = bb.getShort();

    if (dataSize >= 16) {
      location = bb.getLong();
      locationFrom = bb.getLong();
    } else {
        // log that we have different size and we cannot extract
        // location and locationFrom it.
    }
    return location;
  }       
  
  // 36 + dataSize + 1 + 1 + keyLength + 8 + 2;
  private int getBufferUsed(final Map<byte[], byte[]> keyDataHolder) {
    int size = 36;
    for (Map.Entry<byte[], byte[]> entry : keyDataHolder.entrySet()) {
      size += 1 + 1 + 8 + 2;
      size += entry.getKey().length;
      size += entry.getValue().length;
    }
    return size;
  }  
}