com.datastax.driver.dse

Class DseCluster

java.lang.Object

com.datastax.driver.core.Cluster

com.datastax.driver.core.DelegatingCluster

com.datastax.driver.dse.DseCluster

All Implemented Interfaces:

Closeable, AutoCloseable

public class DseCluster
extends DelegatingCluster

Information and known state of a DSE cluster.

This is the main entry point of the DSE driver. It extends the CQL driver's Cluster object with DSE-specific features. A simple example of access to a DSE cluster would be:

   DseCluster cluster = DseCluster.builder().addContactPoint("192.168.0.1").build();
   DseSession session = cluster.connect("db1");

   for (Row row : session.execute("SELECT * FROM table1"))
       // do something ...
 

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DseCluster.Builder Helper class to build DseCluster instances.

Nested classes/interfaces inherited from class com.datastax.driver.core.Cluster

Cluster.Initializer

Method Summary

Modifier and Type	Method and Description
static DseCluster.Builder	builder() Creates a new DseCluster.Builder instance.
DseSession	connect() Creates a new DSE session on this cluster and initializes it.
DseSession	connect(String keyspace) Creates a new DSE session on this cluster, initializes it and sets the keyspace to the provided one.
ListenableFuture<Session>	connectAsync() Creates a new DSE session on this cluster and initializes it asynchronously.
ListenableFuture<Session>	connectAsync(String keyspace) Creates a new DSE session on this cluster, and initializes it to the given keyspace asynchronously.
protected Cluster	delegate() Returns the delegate instance where all calls will be forwarded.
DseConfiguration	getConfiguration() The cluster configuration.
static String	getDseDriverVersion() Returns the current version of the DSE driver.
DseSession	newSession() Creates a new DSE session on this cluster but does not initialize it.

Methods inherited from class com.datastax.driver.core.DelegatingCluster

close, closeAsync, getId, getMetadata, getMetrics, init, isClosed, register, register, register, unregister, unregister, unregister

Methods inherited from class com.datastax.driver.core.Cluster

buildFrom, getClusterName, getDriverVersion, logDriverVersion

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getDseDriverVersion

public static String getDseDriverVersion()

Returns the current version of the DSE driver.

This is intended for products that wrap or extend the driver, as a way to check compatibility if end-users override the driver version in their application.

This method is an alias for Cluster.getDriverVersion(); both return exactly the same version.

Returns:

the DSE driver version.

builder

public static DseCluster.Builder builder()

Creates a new DseCluster.Builder instance.

This is a convenience method for new GraphCluster.Builder().

Returns:

the new cluster builder.

getConfiguration

public DseConfiguration getConfiguration()

Description copied from class: Cluster

The cluster configuration.

Overrides:

getConfiguration in class DelegatingCluster

Returns:

the cluster configuration.

delegate

protected Cluster delegate()

Description copied from class: DelegatingCluster

Returns the delegate instance where all calls will be forwarded.

Specified by:

delegate in class DelegatingCluster

Returns:

the delegate.

newSession

public DseSession newSession()

Creates a new DSE session on this cluster but does not initialize it.

Because this method does not perform any initialization, it cannot fail. The initialization of the session (the connection of the session to the Cassandra nodes) will occur if either the DseSession.init() method is called explicitly, or whenever the returned object is used.

Once a session returned by this method gets initialized (see above), it will be set to no keyspace. If you want to set such session to a keyspace, you will have to explicitly execute a 'USE mykeyspace' query.

Note that if you do not particularly need to defer initialization, it is simpler to use one of the connect() methods of this class.

Overrides:

newSession in class DelegatingCluster

Returns:

a new, non-initialized DSE session on this cluster.

connect

public DseSession connect()

Creates a new DSE session on this cluster and initializes it.

This method will initialize the newly created session, trying to connect to the Cassandra nodes before returning. If you only want to create a session without initializing it right away, see newSession().

Overrides:

connect in class DelegatingCluster

Returns:

a new session on this cluster set to no keyspace.

Throws:

NoHostAvailableException - if the Cluster has not been initialized yet (DelegatingCluster.init() has not be called and this is the first connect call) and no host amongst the contact points can be reached.

AuthenticationException - if an authentication error occurs while contacting the initial contact points.

IllegalStateException - if the Cluster was closed prior to calling this method. This can occur either directly (through DelegatingCluster.close() or DelegatingCluster.closeAsync()), or as a result of an error while initializing the Cluster.

connect

public DseSession connect(String keyspace)

Creates a new DSE session on this cluster, initializes it and sets the keyspace to the provided one.

This method will initialize the newly created session, trying to connect to the Cassandra nodes before returning. If you only want to create a session without initializing it right away, see newSession().

The keyspace set through this method is only valid for CQL queries; for graph queries, the graph to target is determined by the graph name specified via GraphStatement.setGraphName(String)} or GraphOptions.setGraphName(String).

Overrides:

connect in class DelegatingCluster

Parameters:

keyspace - the name of the keyspace to use for the created DseSession.

Returns:

a new session on this cluster set to keyspace keyspace.

Throws:

NoHostAvailableException - if the Cluster has not been initialized yet (DelegatingCluster.init() has not be called and this is the first connect call) and no host amongst the contact points can be reached, or if no host can be contacted to set the keyspace.

AuthenticationException - if an authentication error occurs while contacting the initial contact points.

InvalidQueryException - if the keyspace does not exist.

IllegalStateException - if the Cluster was closed prior to calling this method. This can occur either directly (through DelegatingCluster.close() or DelegatingCluster.closeAsync()), or as a result of an error while initializing the Cluster.

connectAsync

public ListenableFuture<Session> connectAsync()

Creates a new DSE session on this cluster and initializes it asynchronously.

This will also initialize the Cluster if needed; note that cluster initialization happens synchronously on the thread that called this method. Therefore it is recommended to initialize the cluster at application startup, and not rely on this method to do it.

The Session object returned by the future's get method can be safely cast to DseSession.

Overrides:

connectAsync in class DelegatingCluster

Returns:

a future that will complete when the session is fully initialized.

Throws:

NoHostAvailableException - if the Cluster has not been initialized yet (DelegatingCluster.init() has not been called and this is the first connect call) and no host amongst the contact points can be reached.

IllegalStateException - if the Cluster was closed prior to calling this method. This can occur either directly (through DelegatingCluster.close() or DelegatingCluster.closeAsync()), or as a result of an error while initializing the Cluster.

See Also:

connect()

connectAsync

public ListenableFuture<Session> connectAsync(String keyspace)

Creates a new DSE session on this cluster, and initializes it to the given keyspace asynchronously.

This will also initialize the Cluster if needed; note that cluster initialization happens synchronously on the thread that called this method. Therefore it is recommended to initialize the cluster at application startup, and not rely on this method to do it.

The keyspace set through this method is only valid for CQL queries; for graph queries, the graph to target is determined by the graph name specified via GraphStatement.setGraphName(String)} or GraphOptions.setGraphName(String).

The Session object returned by the future's get method can be safely cast to DseSession.

Overrides:

connectAsync in class DelegatingCluster

Parameters:

keyspace - The name of the keyspace to use for the created Session.

Returns:

a future that will complete when the session is fully initialized.

Throws:

NoHostAvailableException - if the Cluster has not been initialized yet (DelegatingCluster.init() has not been called and this is the first connect call) and no host amongst the contact points can be reached.

IllegalStateException - if the Cluster was closed prior to calling this method. This can occur either directly (through DelegatingCluster.close() or DelegatingCluster.closeAsync()), or as a result of an error while initializing the Cluster.