Module org.tentackle.database

Package org.tentackle.dbms

Class ManagedConnectionMonitor

java.lang.Object

java.lang.Thread

org.tentackle.dbms.ManagedConnectionMonitor

All Implemented Interfaces:

Runnable

@Service(ManagedConnectionMonitor.class)
public class ManagedConnectionMonitor
extends Thread

Maintains a set of all open managed connections.
The connections are held by a weak reference and the set is cleaned up once a minute.
Optionally, idle connections with ManagedConnection.isConnectionVerificationNecessary() == true will be verified (via dummy selects) periodically and to prevent premature closing by the database backend. This is especially useful for databases running in the cloud, where the idle connection interval cannot be deactivated or made longer than the idle times maintained by the MpxConnectionManager.

Notice: the monitor thread never stops! It is started when first referenced by getInstance().

Nested Class Summary

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

Thread.Builder, Thread.State, Thread.UncaughtExceptionHandler

Field Summary

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Constructors

Constructor	Description
ManagedConnectionMonitor()	Creates the monitor thread.

Method Summary

Modifier and Type	Method	Description
static ManagedConnectionMonitor	getInstance()	Gets the running monitor thread.
Collection<ManagedConnection>	getManagedConnections()	Gets a list of all open managed connections.
protected void	inspect(ManagedConnection managedConnection, long currentTimeMillis)	Inspects the idle connection.
static boolean	isRunning()	Returns whether the monitor is running. Useful to avoid getInstance() since this will start it, if not running yet.
protected void	loop()	A single loop run.
protected void	pause()	Pauses the thread between loop runs.
void	registerManagedConnection(ManagedConnection managedConnection)	Registers a managed connection.
void	run()

Methods inherited from class java.lang.Thread

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

Methods inherited from class java.lang.Object

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

Constructor Details

ManagedConnectionMonitor

public ManagedConnectionMonitor()

Creates the monitor thread.

Method Details

getInstance

public static ManagedConnectionMonitor getInstance()

Gets the running monitor thread.

Returns:

the thread (singleton)

isRunning

public static boolean isRunning()

Returns whether the monitor is running.
Useful to avoid getInstance() since this will start it, if not running yet.

Returns:

true if running, false if no ManagedConnections created ever (remote server, for example)

registerManagedConnection

public void registerManagedConnection(ManagedConnection managedConnection)

Registers a managed connection.

Parameters:

managedConnection - the managed connection

getManagedConnections

public Collection<ManagedConnection> getManagedConnections()

Gets a list of all open managed connections.

Returns:

the open connections

run

public void run()

Specified by:

run in interface Runnable

Overrides:

run in class Thread

pause

protected void pause()

Pauses the thread between loop runs.

loop

protected void loop()

A single loop run.

inspect

protected void inspect(ManagedConnection managedConnection,
 long currentTimeMillis)

Inspects the idle connection.

Parameters:

managedConnection - the connection

currentTimeMillis - the current epochal time