org.apache.tinkerpop.gremlin.driver

Class Cluster

java.lang.Object

org.apache.tinkerpop.gremlin.driver.Cluster

public final class Cluster
extends Object

A connection to a set of one or more Gremlin Server instances.

Author:

Stephen Mallette (http://stephen.genoprime.com)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Cluster.Builder

Method Summary

Modifier and Type	Method and Description
List<URI>	availableHosts() Gets the list of hosts that the Cluster was able to connect to.
static Cluster.Builder	build()
static Cluster.Builder	build(File configurationFile)
static Cluster.Builder	build(String address)
void	close()
CompletableFuture<Void>	closeAsync()
<T extends Client> T	connect() Creates a Client.ClusteredClient instance to this Cluster, meaning requests will be routed to one or more servers (depending on the cluster configuration), where each request represents the entirety of a transaction.
<T extends Client> T	connect(String sessionId) Creates a Client.SessionedClient instance to this Cluster, meaning requests will be routed to a single server (randomly selected from the cluster), where the same bindings will be available on each request.
<T extends Client> T	connect(String sessionId, boolean manageTransactions) Creates a Client.SessionedClient instance to this Cluster, meaning requests will be routed to a single server (randomly selected from the cluster), where the same bindings will be available on each request.
void	init()
boolean	isClosed() Determines if the Cluster has completed its closing process after a call to close() or closeAsync().
boolean	isClosing() Determines if the Cluster is in the process of closing given a call to close() or closeAsync().
static Cluster	open() Create a Cluster with all default settings which will connect to one contact point at localhost.
static Cluster	open(String configurationFile) Create a Cluster using a YAML-based configuration file.
String	toString()

Methods inherited from class java.lang.Object

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

Method Detail

init

public void init()

connect

public <T extends Client> T connect()

Creates a Client.ClusteredClient instance to this Cluster, meaning requests will be routed to one or more servers (depending on the cluster configuration), where each request represents the entirety of a transaction. A commit or rollback (in case of error) is automatically executed at the end of the request.

Note that calling this method does not imply that a connection is made to the server itself at this point. Therefore, if there is only one server specified in the Cluster and that server is not available an error will not be raised at this point. Connections get initialized in the Client when a request is submitted or can be directly initialized via Client.init().

connect

public <T extends Client> T connect(String sessionId)

Creates a Client.SessionedClient instance to this Cluster, meaning requests will be routed to a single server (randomly selected from the cluster), where the same bindings will be available on each request. Requests are bound to the same thread on the server and thus transactions may extend beyond the bounds of a single request. The transactions are managed by the user and must be committed or rolled-back manually.

Note that calling this method does not imply that a connection is made to the server itself at this point. Therefore, if there is only one server specified in the Cluster and that server is not available an error will not be raised at this point. Connections get initialized in the Client when a request is submitted or can be directly initialized via Client.init().

Parameters:

sessionId - user supplied id for the session which should be unique (a UUID is ideal).

connect

public <T extends Client> T connect(String sessionId,
                                    boolean manageTransactions)

Creates a Client.SessionedClient instance to this Cluster, meaning requests will be routed to a single server (randomly selected from the cluster), where the same bindings will be available on each request. Requests are bound to the same thread on the server and thus transactions may extend beyond the bounds of a single request. If manageTransactions is set to false then transactions are managed by the user and must be committed or rolled-back manually. When set to true the transaction is committed or rolled-back at the end of each request.

Note that calling this method does not imply that a connection is made to the server itself at this point. Therefore, if there is only one server specified in the Cluster and that server is not available an error will not be raised at this point. Connections get initialized in the Client when a request is submitted or can be directly initialized via Client.init().

Parameters:

sessionId - user supplied id for the session which should be unique (a UUID is ideal).

manageTransactions - enables auto-transactions when set to true

toString

public String toString()

Overrides:

toString in class Object

build

public static Cluster.Builder build()

build

public static Cluster.Builder build(String address)

build

public static Cluster.Builder build(File configurationFile)
                             throws FileNotFoundException

Throws:

FileNotFoundException

open

public static Cluster open()

Create a Cluster with all default settings which will connect to one contact point at localhost.

open

public static Cluster open(String configurationFile)
                    throws Exception

Create a Cluster using a YAML-based configuration file.

Throws:

Exception

close

public void close()

closeAsync

public CompletableFuture<Void> closeAsync()

isClosing

public boolean isClosing()

Determines if the Cluster is in the process of closing given a call to close() or closeAsync().

isClosed

public boolean isClosed()

Determines if the Cluster has completed its closing process after a call to close() or closeAsync().

availableHosts

public List<URI> availableHosts()

Gets the list of hosts that the Cluster was able to connect to. A Host is assumed unavailable until a connection to it is proven to be present. This will not happen until the Client submits requests that succeed in reaching a server at the Host or Client.init() is called which initializes the ConnectionPool for the Client itself. The number of available hosts returned from this method will change as different servers come on and offline.