org.trippi.impl.base
Class ConfigurableSessionPool

java.lang.Object
  java.lang.Thread
      org.trippi.impl.base.ConfigurableSessionPool

All Implemented Interfaces:

java.lang.Runnable, TriplestoreSessionPool

public class ConfigurableSessionPool
extends java.lang.Thread
implements TriplestoreSessionPool

A configurable TriplestoreSessionPool that proactively increases pool size.

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

ConfigurableSessionPool(TriplestoreSessionFactory factory, int initialSize, int maxGrowth, int spareSessions)
Initialize the pool and grow it to its initial size.

Method Summary

void	close() Close all sessions.
void	finalize() Call close() at garbage collection time in case it hasn't been called yet.
TriplestoreSession	get() Get a connection from the pool.
int	getFreeCount() Get the number of sessions not currently in use.
int	getInUseCount() Get the number of sessions currently in use.
java.lang.String[]	listTripleLanguages()
java.lang.String[]	listTupleLanguages()
void	release(TriplestoreSession session) Release a connection back to the pool.
void	run() Maintain the pool size.

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Constructor Detail

ConfigurableSessionPool

public ConfigurableSessionPool(TriplestoreSessionFactory factory,
                               int initialSize,
                               int maxGrowth,
                               int spareSessions)
                        throws TrippiException

Initialize the pool and grow it to its initial size. This also starts a background thread that maintains the pool's size.

Parameters:

initialSize - number of sessions to start with.

maxGrowth - max additional sessions to add. If -1, no limit will be placed on the size.

spareSessions - number of unused sessions to keep available. Zero means new sessions will only be created on demand. Note if maxGrowth is 0, the value of this parameter is inconsequential.

Throws:

TrippiException

Method Detail

listTripleLanguages

public java.lang.String[] listTripleLanguages()

Specified by:

listTripleLanguages in interface TriplestoreSessionPool

listTupleLanguages

public java.lang.String[] listTupleLanguages()

Specified by:

listTupleLanguages in interface TriplestoreSessionPool

get

public TriplestoreSession get()
                       throws TrippiException

Get a connection from the pool.

Specified by:

get in interface TriplestoreSessionPool

Returns:

a session, or null if none are available and growth isnt allowed.

Throws:

TrippiException - if there were no spare sessions and an attempt to create one on-demand failed.

release

public void release(TriplestoreSession session)

Release a connection back to the pool.

Specified by:

release in interface TriplestoreSessionPool

getInUseCount

public int getInUseCount()

Get the number of sessions currently in use.

Specified by:

getInUseCount in interface TriplestoreSessionPool

getFreeCount

public int getFreeCount()

Get the number of sessions not currently in use.

Specified by:

getFreeCount in interface TriplestoreSessionPool

run

public void run()

Maintain the pool size. This just ensures that pool growth occurs when necessary, checking every 1/4 of a second.

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread

close

public void close()
           throws TrippiException

Close all sessions. This also stops the pool maintenance thread. It should only be called when finished with the session pool.

Specified by:

close in interface TriplestoreSessionPool

Throws:

TrippiException

finalize

public void finalize()
              throws TrippiException

Call close() at garbage collection time in case it hasn't been called yet.

Overrides:

finalize in class java.lang.Object

Throws:

TrippiException