Obteniendo una excepción al usar Google Pubsub para enumerar temas, mi aplicación web se ejecuta en tomcat.

public static List<String> listTopics(GcpCredentials gcCredentials, String project) throws GCPException, IOException
{
    List<String> topics = new ArrayList<>();
    TopicAdminClient client = getTopicClient(gcCredentials);
    ProjectName projectName = ProjectName.create(project);
    ListTopicsPagedResponse response = client.listTopics(projectName);
    for (Topic topic :response.iterateAll())
    {
        topics.add(topic.getNameAsTopicName().getTopic());
    }
    return topics;
}`

Excepción:

java.lang.IllegalArgumentException: Jetty ALPN / NPN no se ha configurado correctamente.
en io.grpc.netty.GrpcSslContexts.selectApplicationProtocolConfig (GrpcSslContexts.java:174) en io.grpc.netty.GrpcSslContexts.configure (GrpcSslConf. .en. ._. .newClientTransport (CallCredentialsApplyingTransportFactory.java:61) en io.grpc.internal.InternalSubchannel.startNewTransport (InternalSubchannel.java:209) en io.grpc.internal.InternalSubchannel.obtainActive Transporte (InternalSubchannel.java:186) en io.grpc.internal.ManagedChannelImpl $ SubchannelImplImpl.obtainActiveTransport (ManagedChannelImpl.java:806) en io.grpc.internal.GrpcUtil.getTransportFromPickResult (GrpcUc.pp.Util.gr. .DelayedClientTransport.reprocess (DelayedClientTransport.java:296) en io.grpc.internal.ManagedChannelImpl $ LbHelperImpl $ 5.run (ManagedChannelImpl.java:724) en io.grpc.internal.ChannelExecutor.drain (Channel87) .grpc.internal.ManagedChannelImpl $ LbHelperImpl.runSerialized (ManagedChannelImpl.java:715) en io.grpc.internal.ManagedChannelImpl $ NameResolverListenerImpl.onUpdate (ManagedChannelImpl.java:752.en.r. java: 174) en java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1142) en java.util.concurrent.ThreadPoolExecutor $ Worker.run (ThreadPoolExecutor.java:617) en java.lang.Tread.run (Thread .java: 745)