我已经阅读并尝试了许多关于这个问题的解决方案，但仍然不适用于我。我得到以下例外： Exception in thread "main" com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: /1.2.3.4:9042 (com.datastax.driver.core.exceptions.TransportException:[/1.2.3.4:9042] Channel has been closed)) 我已将驱动程序更新到最新版本。cassandra.yaml配置如下： start_native_transport: true native_transport_port: 9042 rpc_address: 0.0.0.0 我可以从datastax devcenter连接到节点，但不能从java连接到节点。我不确定问题出在哪里。
这是我在java中使用的代码。

public class ClientToNodeConnection {

  public static Logger logger = 
LoggerFactory.getLogger(ClientToNodeConnection.class);

  public static void main(String[] args) {

    ClientToNodeConnection l = new ClientToNodeConnection();

    l.execute();
  }

  private void execute() {
    Cluster cluster;
    Session session;

    logger.info("Login into {}");

    cluster = getCluster("/client-keystore.jks", "keypass", "1.2.3.4");

    // Connect to the cluster and keyspace "ssl"
    session = cluster.newSession();

    session.execute(" CREATE KEYSPACE IF NOT EXISTS ssl WITH replication = {'class':'SimpleStrategy', 'replication_factor':1};");

    session.execute("use ssl;");
    session.execute("CREATE TABLE IF NOT EXISTS songs (title text, lyrics text, PRIMARY KEY (title))");

    // Insert one record into the users table
    session.execute("INSERT INTO songs (title, lyrics) VALUES ('Don''t believe the hype', 'Caught you lookin for the same thing It''s a new thing check out this I bring')");

    // Use select to get the user we just entered
    ResultSet results = session.execute("SELECT * FROM songs Limit 200;");
    for (Row row : results) {
      logger.info("***data extracted***");
      logger.info("{} - {}", row.getString("title"), row.getString("lyrics"));
    }

    session.close();

    // Clean up the connection by closing it
    cluster.close();
  }

  // This method is an example of loading a truststore from a resource, decoding it with its password.
  private Cluster getCluster(String trustStoreLocation, String trustStorePassword, String host) {
    Cluster cluster;
    SSLContext sslcontext = null;

    try {

      InputStream is = ClientToNode.class.getResourceAsStream(trustStoreLocation);
      KeyStore keystore = KeyStore.getInstance("jks");
      char[] pwd = trustStorePassword.toCharArray();
      keystore.load(is, pwd);

      TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
      tmf.init(keystore);
      TrustManager[] tm = tmf.getTrustManagers();

      sslcontext = SSLContext.getInstance("TLS");
      sslcontext.init(null, tm, null);
    } catch (KeyStoreException kse) {
      logger.error(kse.getMessage(), kse);
    } catch (CertificateException e) {
      logger.error(e.getMessage(), e);
    } catch (NoSuchAlgorithmException e) {
      logger.error(e.getMessage(), e);
    } catch (KeyManagementException e) {
      logger.error(e.getMessage(), e);
    } catch (IOException e) {
      logger.error(e.getMessage(), e);
    }

    JdkSSLOptions sslOptions = JdkSSLOptions.builder()
      .withSSLContext(sslcontext)
      .build();

    cluster = Cluster.builder()
      .withClusterName("cassandra")
      .withCredentials("casss", "cass")
      .addContactPoint(host)
      .withPort(9042)
      .withProtocolVersion(ProtocolVersion.V3)
      .withSSL(sslOptions)
      .build();

    return cluster;
  }

}