@Override
  public int getSerializedSize() {
    int size = memoizedSize;
    if (size != -1) return size;

    size = 0;
    if (!com.google.protobuf.GeneratedMessage.isStringEmpty(url_)) {
      size += com.google.protobuf.GeneratedMessage.computeStringSize(1, url_);
    }
    if (!com.google.protobuf.GeneratedMessage.isStringEmpty(userId_)) {
      size += com.google.protobuf.GeneratedMessage.computeStringSize(2, userId_);
    }
    if (!com.google.protobuf.GeneratedMessage.isStringEmpty(sessionId_)) {
      size += com.google.protobuf.GeneratedMessage.computeStringSize(3, sessionId_);
    }
    if (timestamp_ != 0L) {
      size += com.google.protobuf.CodedOutputStream
        .computeInt64Size(4, timestamp_);
    }
    if (duration_ != 0L) {
      size += com.google.protobuf.CodedOutputStream
        .computeInt64Size(5, duration_);
    }
    if (!com.google.protobuf.GeneratedMessage.isStringEmpty(event_)) {
      size += com.google.protobuf.GeneratedMessage.computeStringSize(6, event_);
    }
    size += getUnknownFields().getSerializedSize();
    memoizedSize = size;
    return size;
  }
<code>string event = 6;</code>
@return The bytes for event.
examples/client/src/main/java/com/clickhouse/examples/protos/UIEvent.java