Java Code Examples for com.datastax.driver.core.Metadata#getAllHosts()

protected Cluster createCluster() {
   Cluster.Builder builder = Cluster.builder();

   if (this.contactPoints != null && !this.contactPoints.isEmpty()) {
      String[] values = new String[this.contactPoints.size()];
      this.contactPoints.toArray(values);
      builder.addContactPoints(values);
   }

   builder.withPort(this.port);

   Cluster cluster = builder.build();

   Metadata metadata = cluster.getMetadata();

   LOG.info("Connected to Cassandra cluster: " + metadata.getClusterName());
   for (Host host : metadata.getAllHosts()) {
      LOG.info("DataCenter: {}, Rack: {}, Host: {}",
               new Object[]{host.getDatacenter(), host.getRack(), host.getAddress()});
   }

   return cluster;
}
 

public void connect(final String node, final Integer port) {

        Builder b = Cluster.builder().addContactPoint(node);

        if (port != null) {
            b.withPort(port);
        }
        cluster = b.build();

        Metadata metadata = cluster.getMetadata();
        LOG.info("Cluster name: " + metadata.getClusterName());

        for (Host host : metadata.getAllHosts()) {
            LOG.info("Datacenter: " + host.getDatacenter() + " Host: " + host.getAddress() + " Rack: " + host.getRack());
        }

        session = cluster.connect();
    }
 

private void displayClusterInfo() {
    Metadata metadata = m_cluster.getMetadata();
    m_logger.info("Connected to cluster with topography:");
    RoundRobinPolicy policy = new RoundRobinPolicy();
    for (Host host : metadata.getAllHosts()) {
        m_logger.info("   Host {}: datacenter: {}, rack: {}, distance: {}",
                      new Object[]{host.getAddress(), host.getDatacenter(), 
            host.getRack(), policy.distance(host)});
    }
    m_logger.info("Database contains {} keyspaces", metadata.getKeyspaces().size());
}
 

@Bean
public Session session() {

    try {

        final Cluster cluster = cluster();
        final Metadata metadata = cluster().getMetadata();

        LOGGER.info("Connected to cluster: {}\n", metadata.getClusterName());

        for (final Host host : metadata.getAllHosts()) {
            LOGGER.info("Datacenter: {}; Host: {}; Rack: {}\n", host.getDatacenter(), host.getAddress(),
                    host.getRack());
        }

        return cluster.connect(getKeyspace());

    } catch (NoHostAvailableException e) {
        LOGGER.info("NoHostAvailableException: {}", e.getMessage());

        return null;
    }

}
 

@Ignore
@Test
public void queryIsExecutedOnAllClusterNodesAndAlsoTheOldestHintIsPicked() {

    // ***** TODO: Get a cluster with 2 nodes. (RUN WITH PERFTEST LATER.....) ******
    // Ignoring this test for now

    // Insert hints on all the cluster nodes.
    Cluster cluster = Cluster.builder()
            .addContactPoint("127.0.0.1")
            .withPort(9164)
            .withLoadBalancingPolicy(new SelectedHostLoadBalancingPolicyForTest())
            .build();
    Metadata metadata = cluster.getMetadata();
    Session clusterSession = cluster.connect();

    long hintTimestamp = System.currentTimeMillis();
    for (Host host : metadata.getAllHosts()) {
        SelectedHostStatement selectedHostStatement = new SelectedHostStatement(new SimpleStatement(getInsertHintsQuery(hintTimestamp)), host);
        clusterSession.execute(selectedHostStatement);
        hintTimestamp = hintTimestamp + 10000;
    }

    // Now check if the query ran on EVERY node of the cluster.
    Assert.assertEquals(ALL_SELECTED_HOSTS.size(), 2);

    // Get the oldest hint Timestamp of the cluster
    ClusterHintsPoller clusterHintsPoller = new ClusterHintsPoller();
    HintsPollerResult oldestHintsInfo = clusterHintsPoller.getOldestHintsInfo(clusterSession);

    // Note: ?? - This will make the test fail even if one node is down or a connection problem with just one node.
    Assert.assertNotNull(oldestHintsInfo);
    Assert.assertEquals(oldestHintsInfo.getAllPolledHosts().size(), 2);

    long retrievedHintTimeStamp = oldestHintsInfo.getOldestHintTimestamp().or(Long.MAX_VALUE);

    Assert.assertEquals(retrievedHintTimeStamp, hintTimestamp);

    cluster.close();
    clusterSession.close();
}
 

public void connect(final String node,
                    final int port) {
    this.sessionLock.lock();

    /*
     * 1. The session may have been closed in between. This may lead to several errors
     *    because the session may be in use by several others. Nevertheless, the
     *    implementation is assumed to be thread-safe, so let's assume that closing is
     *    too.
     * 2. The session may have never been created. In both cases, entering this block
     *    we have to create the instances.
     */
    try {

        // if we have a session meanwhile, just return
        if (this.session != null) {
            return;
        } else if (this.cluster == null) {
            this.cluster = Cluster.builder().addContactPoint(node).withPort(port).build();
            final Metadata metadata = this.cluster.getMetadata();

            if (LOGGER.isInfoEnabled()) {
                LOGGER.info(String.format("Connected to cluster: %s", metadata.getClusterName()));

                for (final Host host : metadata.getAllHosts()) {
                    LOGGER.info(String.format("Datacenter: %s; Host: %s; Rack: %s",
                            host.getDatacenter(), host.getAddress(), host.getRack()));
                }
            }
        }

        this.session = this.cluster.connect();
    } catch (final Exception e) {
        final String msg = String.format("Unable to open a connection at '%s:%d (%s)'.", node, port, this.keySpace);

        /*
         * Reset the cluster, normally the current one won't work:
         * Caused by: java.lang.IllegalStateException:
         * Can't use this cluster instance because it was previously closed
         * at com.datastax.driver.core.Cluster.checkNotClosed(Cluster.java:602)
         * at com.datastax.driver.core.Cluster.connectAsync(Cluster.java:333)
         * at com.datastax.driver.core.Cluster.connectAsync(Cluster.java:309)
         * at com.datastax.driver.core.Cluster.connect(Cluster.java:251)
         * at com.brein.common.cassa.CassaSessionManager.setup(CassaSessionManager.java:94)
         */
        try {
            this.cluster.close();
        } catch (final Exception ignore) {
            // ignore
        }
        this.cluster = null;

        // now we can throw the exception
        throw new FailedConnection(msg, e);
    } finally {
        this.sessionLock.unlock();
    }

    createKeySpace();
    createColumnFamily();
}
 

private void establishSessionWithPolicies()
{
  Cluster.Builder clusterBuilder = Cluster.builder();
  String[] seedNodesSplit = seedNodesStr.split(";");
  Collection<InetAddress> allSeeds = new ArrayList<>();
  Set<String> allKnownPorts = new HashSet<>();
  for (String seedNode : seedNodesSplit) {
    String[] nodeAndPort = seedNode.split(":");
    if (nodeAndPort.length > 1) {
      allKnownPorts.add(nodeAndPort[1]);
    }
    try {
      allSeeds.add(InetAddress.getByName(nodeAndPort[0]));
    } catch (UnknownHostException e) {
      LOG.error(" Error while trying to initialize the seed brokers for the cassandra cluster " + e.getMessage(), e);
    }
  }
  clusterBuilder = clusterBuilder.addContactPoints(allSeeds);
  clusterBuilder
    .withClusterName(clusterName)
    // We can fail if all of the nodes die in the local DC
    .withLoadBalancingPolicy(loadBalancingPolicy)
    // Want Strong consistency
    .withRetryPolicy(retryPolicy)
    // Tolerate some nodes down
    .withQueryOptions(queryOptions)
    // Keep establishing connections after detecting a node down
    .withReconnectionPolicy(reconnectionPolicy);
  // Finally initialize the cluster info
  if (allKnownPorts.size() > 0) {
    int shortlistedPort = Integer.parseInt(allKnownPorts.iterator().next());
    clusterBuilder = clusterBuilder.withPort(shortlistedPort);
  }
  cluster = clusterBuilder.build();
  Metadata metadata = cluster.getMetadata();
  LOG.info("Connected to cluster: \n" + metadata.getClusterName());
  for (Host host : metadata.getAllHosts()) {
    LOG.info(String.format("Datacenter: %s; Host: %s; Rack: %s\n",
        host.getDatacenter(), host.getAddress(), host.getRack()));
  }
  session = cluster.connect(keyspaceName);
}