Are the OpusDecoder structure and related methods thread-safe?

Hi,

I am using the class org.jitsi.impl.neomedia.codec.audio.opus.Opus to decode/encode some packets in a multi-thread context, I wonder if the OpusDecoder structure and related methods are thread-safe? does the following method testMethod work in a multi-thread context?

public class TestOpus {
    private static long opusState= Opus.decoder_create(48000, 1);
    public long testMethod(byte[] packetData){
        return Opus.decoder_get_nb_samples(opusState, packetData, 0, packetData.length);
    }
}

Thanks.