TS3J is an open-source implementation of the reverse-engineered Teamspeak3 full server/client protocol, as an adaptation of Splamy's C# TS3Client source code. You can find that here: https://github.com/Splamy/TS3AudioBot/.

Maven

If you want the latest -SNAPSHOT:

	<repositories>
		<repository>
		    <id>jitpack.io</id>
		    <url>https://jitpack.io</url>
		</repository>
	</repositories>
   <dependency>
	    <groupId>com.github.manevolent</groupId>
	    <artifactId>ts3j</artifactId>
	    <version>-SNAPSHOT</version>
	</dependency>

Connection & Basic Setup

client = new LocalTeamspeakClientSocket();

// Set up client
client.setIdentity(identity);
client.addListener(listener);
client.setNickname(nickname);

client.connect(
   new InetSocketAddress(
        InetAddress.getByName(address),
        port // UDP client port, Teamspeak3 client uses 9987
   ),
   password,
   10000L
);

// Subscribe to all channels
client.subscribeAll();

// Get list of clients
for (Client basicClient : client.listClients())
	recognizeClient(client.getClientInfo(basicClient.getId()));

Note that while connect() is processing, you'll receive channels registered and clients currently connected to the server. It is important that you use the listener to collect these, and track their changes through the other listener event calls.

You can interact with the server using the commands on the client object similarly to TS3Query.

Handling chat

// TS3Listener interface
@Override
public void onTextMessage(TextMessageEvent textMessageEvent) {
	if (textMessageEvent.getInvokerId() == client.getClientId())
    		return;

	// Global chat example
	client.sendServerMessage("Echo!");
	
	// PM to the sender
	client.sendPrivateMessage(textMessageEvent.getInvokerId(), "Echo!");
}

Sending audio

// Microphone interface
public void write(float[] buffer, int len) {
	byte[] opusPacket = doOpusEncodingHere(buffer, len);

	packetQueue.add(opusPacket);
}

@Override
public boolean isReady() {
	return true;
}

@Override
public CodecType getCodec() {
	return CodecType.OPUS_MUSIC;
}

@Override
public byte[] provide() {
	try {
	    if (packetQueue.peek() == null)
		return new byte[0]; // underflow

	    OpusPacket packet = packetQueue.remove();

	    if (packet == null)
		return new byte[0]; // underflow

	    return packet.getBytes();
	} catch (NoSuchElementException ex) {
	    return new byte[0]; // signals the decoder on the clients to stop
	}
}

Receiving audio

Refer to the setVoiceHandler and setWhisperHandler methods to supply a Consumer object to receive Voice and Whisper packets. You will need to decode the packets yourself, and insert packet-loss-correction as needed.