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

        size = 0;
        if (!com.google.protobuf.GeneratedMessage.isStringEmpty(participantSid_)) {
            size += com.google.protobuf.GeneratedMessage.computeStringSize(1, participantSid_);
        }
        if (!payload_.isEmpty()) {
            size += com.google.protobuf.CodedOutputStream.computeBytesSize(2, payload_);
        }
        {
            int dataSize = 0;
            for (int i = 0; i < destinationSids_.size(); i++) {
                dataSize += computeStringSizeNoTag(destinationSids_.getRaw(i));
            }
            size += dataSize;
            size += getDestinationSidsList().size();
        }
        if (((bitField0_ & 0x00000001) != 0)) {
            size += com.google.protobuf.GeneratedMessage.computeStringSize(4, topic_);
        }
        if (!com.google.protobuf.GeneratedMessage.isStringEmpty(participantIdentity_)) {
            size += com.google.protobuf.GeneratedMessage.computeStringSize(5, participantIdentity_);
        }
        {
            int dataSize = 0;
            for (int i = 0; i < destinationIdentities_.size(); i++) {
                dataSize += computeStringSizeNoTag(destinationIdentities_.getRaw(i));
            }
            size += dataSize;
            size += getDestinationIdentitiesList().size();
        }
        size += getUnknownFields().getSerializedSize();
        memoizedSize = size;
        return size;
    }
<pre>
topic under which the message was published
</pre>

<code>optional string topic = 4;</code>

@return The bytes for topic.
turms-plugins/turms-plugin-livekit/src/main/java/im/turms/plugin/livekit/core/proto/models/UserPacket.java