Class ConnectionMonitor

java.lang.Object

java.lang.Thread

clazzfish.monitor.util.Shutdowner

clazzfish.monitor.AbstractMonitor

clazzfish.jdbc.ConnectionMonitor

All Implemented Interfaces:

ConnectionMonitorMBean, AbstractMonitorMBean, Shutdownable, Runnable

public class ConnectionMonitor
extends AbstractMonitor
implements ConnectionMonitorMBean

This is the monitor class for the ProxyConnection which monitors the different newInstance() and close() calls. So you can ask this monitor how many connections and which connections are open.

The instance of this class is automatically registered as MBean as soon as a ProxyConnection is used.

Originally this class was part of PatternTesting (since 2012) but was moved in 2018 to the ClazzFish project.

Since:

0.9

Author:

oliver (ob@aosd.de)

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

Modifier	Constructor	Description
protected	ConnectionMonitor()	No need to instantiate it - we provide only some services.

Method Summary

Modifier and Type	Method	Description
static void	addConnection(ProxyConnection proxyConnection)	Adds the connection to the list of open connections.
static void	assertConnectionsClosed()	Assert that all connections are closed.
void	dumpMe(File dumpDir)	This operation dumps the different MBean attributes to the given directory.
static StackTraceElement	getCallerOf(Connection connection)	Gets the caller of the given connection.
StackTraceElement[]	getCallers()	Gets the callers.
TabularData	getCallerStacktraces()	Gets the caller stacktraces of all connections.
int	getClosedConnections()	Gets the number of closed connections.
static ConnectionMonitor	getInstance()	Yes, it is a Singleton because it offers only some services.
StackTraceElement	getLastCaller()	Gets the caller which opens the last connection.
StackTraceElement[]	getLastCallerStacktrace()	Gets the stacktrace of the caller which opens the last connection.
static Connection	getMonitoredConnection(Connection connection)	If you want to monitor the connection use this method.
int	getOpenConnections()	Gets the number of open connections.
int	getSumOfConnections()	Gets the total sum of open and closed connections.
void	logCallerStacktraces()	Log the caller stacktraces.
void	logMe()	Logs the different array to the log output.
static void	removeConnection(ProxyConnection proxyConnection)	Removes the connection from the list of open connections.
void	run()	This method is called when the ConnectionMonitor is registered as shutdown hook.
String	toString()	This toString implementation supports logging and debugging by showing the number of open connections.

Methods inherited from class clazzfish.monitor.AbstractMonitor

copyResource, dump, dump, dumpArray, dumpArray, dumpHeadline, dumpMe, dumpMe, getDumpDir, isMBean, registerMeAsMBean, registerMeAsMBean, registerMeAsMBean, toStringArray, unregisterMeAsMBean

Methods inherited from class clazzfish.monitor.util.Shutdowner

addMeAsShutdownHook, isShutdownHook, removeMeAsShutdownHook

Methods inherited from class java.lang.Thread

activeCount, checkAccess, clone, 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, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, sleep, start, startVirtualThread, stop, threadId, yield

Methods inherited from class java.lang.Object

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

Methods inherited from interface clazzfish.monitor.AbstractMonitorMBean

dumpMe, dumpMe, getDumpDir

Methods inherited from interface clazzfish.jdbc.ConnectionMonitorMBean

addMeAsShutdownHook, isShutdownHook, removeMeAsShutdownHook

Constructor Details

ConnectionMonitor

protected ConnectionMonitor()

No need to instantiate it - we provide only some services. The constructor is protected because it is still used by the (deprecated) ConnectionMonitor in patterntesting.runtime.db.

Method Details

getInstance

public static ConnectionMonitor getInstance()

Yes, it is a Singleton because it offers only some services. So we don't need the object twice.

Returns:

the only instance

getMonitoredConnection

public static Connection getMonitoredConnection(Connection connection)

If you want to monitor the connection use this method.

Parameters:

connection - the original connection

Returns:

a proxy for the connection

addConnection

public static void addConnection(ProxyConnection proxyConnection)

Adds the connection to the list of open connections.

Parameters:

proxyConnection - the proxy connection

removeConnection

public static void removeConnection(ProxyConnection proxyConnection)

Removes the connection from the list of open connections.

Parameters:

proxyConnection - the proxy connection

getCallerOf

public static StackTraceElement getCallerOf(Connection connection)

Gets the caller of the given connection.

Parameters:

connection - the connection

Returns:

the caller of the connection

getCallers

public StackTraceElement[] getCallers()

Gets the callers.

Specified by:

getCallers in interface ConnectionMonitorMBean

Returns:

the callers

See Also:

• ConnectionMonitorMBean.getCallers()

getLastCallerStacktrace

public StackTraceElement[] getLastCallerStacktrace()

Gets the stacktrace of the caller which opens the last connection.

Specified by:

getLastCallerStacktrace in interface ConnectionMonitorMBean

Returns:

the all caller

getCallerStacktraces

public TabularData getCallerStacktraces()
                                 throws OpenDataException

Gets the caller stacktraces of all connections.

Specified by:

getCallerStacktraces in interface ConnectionMonitorMBean

Returns:

stacktraces of all callers

Throws:

OpenDataException - the open data exception

getLastCaller

public StackTraceElement getLastCaller()

Gets the caller which opens the last connection.

Specified by:

getLastCaller in interface ConnectionMonitorMBean

Returns:

the all caller

getOpenConnections

public int getOpenConnections()

Gets the number of open connections.

Specified by:

getOpenConnections in interface ConnectionMonitorMBean

Returns:

the open count

See Also:

• ConnectionMonitorMBean.getOpenConnections()

getClosedConnections

public int getClosedConnections()

Gets the number of closed connections.

Specified by:

getClosedConnections in interface ConnectionMonitorMBean

Returns:

the closed connections

Since:

1.4.1

getSumOfConnections

public int getSumOfConnections()

Gets the total sum of open and closed connections.

Specified by:

getSumOfConnections in interface ConnectionMonitorMBean

Returns:

the sum of connections

Since:

1.4.1

assertConnectionsClosed

public static void assertConnectionsClosed()

Assert that all connections are closed.

toString

public String toString()

This toString implementation supports logging and debugging by showing the number of open connections.

Overrides:

toString in class AbstractMonitor

Returns:

the string

See Also:

• Object.toString()

dumpMe

public void dumpMe(File dumpDir)
            throws IOException

This operation dumps the different MBean attributes to the given directory.

Overrides:

dumpMe in class AbstractMonitor

Parameters:

dumpDir - the directory where the attributes are dumped to.

Throws:

IOException - Signals that an I/O exception has occurred.

logMe

public void logMe()

Logs the different array to the log output.

Specified by:

logMe in interface AbstractMonitorMBean

Specified by:

logMe in class AbstractMonitor

logCallerStacktraces

public void logCallerStacktraces()

Log the caller stacktraces.

Specified by:

logCallerStacktraces in interface ConnectionMonitorMBean

Since:

1.6.1

See Also:

• ConnectionMonitorMBean.logCallerStacktraces()

run

public void run()

This method is called when the ConnectionMonitor is registered as shutdown hook.

Specified by:

run in interface Runnable

Overrides:

run in class AbstractMonitor

See Also:

• Thread.run()