org.apache.tinkerpop.gremlin.server.handler

Class MultiTaskSession

java.lang.Object

org.apache.tinkerpop.gremlin.server.handler.AbstractSession

org.apache.tinkerpop.gremlin.server.handler.MultiTaskSession

All Implemented Interfaces:

AutoCloseable, Runnable, Session

public class MultiTaskSession
extends AbstractSession

A Session implementation that queues tasks given to it and executes them in a serial fashion within the same thread which thus allows multiple tasks to be executed in the same transaction. The first SessionTask to execute is supplied on the constructor and additional ones may be added as they arrive with submitTask(SessionTask) where they will be added to a queue where they will await execution in the thread bound to this session.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.tinkerpop.gremlin.server.handler.AbstractSession

AbstractSession.CloseReason

Field Summary

Fields

Modifier and Type	Field and Description
protected BlockingQueue<SessionTask>	queue

Fields inherited from class org.apache.tinkerpop.gremlin.server.handler.AbstractSession

aliasesUsedBySession, closeReason, graphManager, maintainStateAfterException, sessions, sessionThread

Fields inherited from interface org.apache.tinkerpop.gremlin.server.handler.Session

evalOpTimer, traversalOpTimer

Constructor Summary

Constructors

Constructor and Description
MultiTaskSession(SessionTask initialSessionTask, String sessionId, ConcurrentMap<String,Session> sessions) Creates a new MultiTaskSession object providing the initial starting SessionTask that gets executed by the session when it starts.

Method Summary

Modifier and Type	Method and Description
void	close() This method stops incoming requests from being added to the session queue.
GremlinScriptEngine	getScriptEngine(SessionTask sessionTask, String language) Gets the script engine specific to this session which is dependent on the Settings.useCommonEngineForSessions configuration.
protected Bindings	getWorkerBindings()
protected GremlinExecutor	initializeGremlinExecutor(SessionTask sessionTask)
boolean	isAcceptingTasks() Determines if this session can accept additional tasks or not.
void	run()
boolean	submitTask(SessionTask sessionTask) Adds a task for session to complete.
String	toString()

Methods inherited from class org.apache.tinkerpop.gremlin.server.handler.AbstractSession

cancel, closeTransaction, closeTransaction, closeTransactionSafely, closeTransactionSafely, determineIfTemporaryException, fromBytecode, fromScript, generateResponseMetaData, generateStatusAttributes, getActualTimeoutLengthWhenClosed, getCloseReason, getSessionId, handleException, handleGraphOperation, handleIterator, isBoundTo, isTransactionManaged, iterateComplete, makeFrame, mergeBindingsFromRequest, process, setSessionCancelFuture, setSessionFuture, startTransaction, triggerTimeout

Methods inherited from class java.lang.Object

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

Field Detail

queue

protected final BlockingQueue<SessionTask> queue

Constructor Detail

MultiTaskSession

public MultiTaskSession(SessionTask initialSessionTask,
                        String sessionId,
                        ConcurrentMap<String,Session> sessions)

Creates a new MultiTaskSession object providing the initial starting SessionTask that gets executed by the session when it starts.

Parameters:

initialSessionTask - The tasks that starts the session.

sessionId - The id of the session

sessions - The session id to Session instances mapping

Method Detail

getScriptEngine

public GremlinScriptEngine getScriptEngine(SessionTask sessionTask,
                                           String language)

Gets the script engine specific to this session which is dependent on the Settings.useCommonEngineForSessions configuration.

Overrides:

getScriptEngine in class AbstractSession

isAcceptingTasks

public boolean isAcceptingTasks()

Description copied from interface: Session

Determines if this session can accept additional tasks or not.

submitTask

public boolean submitTask(SessionTask sessionTask)
                   throws RejectedExecutionException

Description copied from interface: Session

Adds a task for session to complete.

Throws:

RejectedExecutionException - if the task cannot be queued

run

public void run()

close

public void close()

This method stops incoming requests from being added to the session queue. It then cancels the session lifetime timeout and then calls super#close() which will then interrupt this run() which will clear out remaining requests in the queue. This latter part of the close, where the interruption is concerned, is an asynchronous operation and will not block as it finishes its processing in the "gremlinPool" thread that was originally handling the work.

Specified by:

close in interface AutoCloseable

Overrides:

close in class AbstractSession

getWorkerBindings

protected Bindings getWorkerBindings()
                              throws SessionException

Overrides:

getWorkerBindings in class AbstractSession

Throws:

SessionException

initializeGremlinExecutor

protected GremlinExecutor initializeGremlinExecutor(SessionTask sessionTask)

toString

public String toString()

Overrides:

toString in class Object