net.jot.db
Class JOTDBPool

java.lang.Object
  java.lang.Thread
      net.jot.db.JOTDBPool

All Implemented Interfaces:

java.lang.Runnable

public class JOTDBPool
extends java.lang.Thread

This is an implementation of a database connection pooling system It manages connections, adds some when needed, and periodically check there status and renew them is they appear corrupt/hung. It also release connections if they aren't used for a while.

Author:

tcolar

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

JOTDBPool(java.lang.String name, JOTDBJDBCSetup setup)
Create appol for a particular DB

Method Summary

void	dropAll() Release/closes all the connections
void	dropConnection(int i) Release/removes a connection
void	finalize() will automatically call shutdown when java app is terminated, to avoid hung DB connections.
void	releaseConnection(java.sql.Connection con, int i) Description of the Method
void	releaseConnection(JOTTaggedConnection con) free a connection when not usefull anymore.
java.sql.Connection	renewConnection(int index) Renew a connection when it got corrupted.
JOTTaggedConnection	retrieveConnection() This get a connection from the pool Returns the "first available".
void	run() The run thread method is there as a whatchdog It will try to find out when connections aren't needed anymore And free them if possible.
void	shutdown() Terminates a pool and releases resources
void	updateAccessTime(int id) Updates the last time a pooled connection was used, so we can manage it better.

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

JOTDBPool

public JOTDBPool(java.lang.String name,
                 JOTDBJDBCSetup setup)

Create appol for a particular DB

Parameters:

setup - Description of Parameter

Method Detail

run

public void run()

The run thread method is there as a whatchdog It will try to find out when connections aren't needed anymore And free them if possible. It also frees "locked" connections. This should be threadsafe.

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread

releaseConnection

public void releaseConnection(JOTTaggedConnection con)

free a connection when not usefull anymore.

Parameters:

con - Description of Parameter

releaseConnection

public void releaseConnection(java.sql.Connection con,
                              int i)

Description of the Method

Parameters:

con - Description of the Parameter

i - Description of the Parameter

retrieveConnection

public JOTTaggedConnection retrieveConnection()

This get a connection from the pool Returns the "first available". This is synchronized since multithread.

Returns:

The connection value

renewConnection

public java.sql.Connection renewConnection(int index)

Renew a connection when it got corrupted.

Parameters:

index - Description of Parameter

Returns:

Description of the Returned Value

dropConnection

public void dropConnection(int i)

Release/removes a connection

Parameters:

i - Description of the Parameter

dropAll

public void dropAll()

Release/closes all the connections

shutdown

public void shutdown()

Terminates a pool and releases resources

finalize

public void finalize()

will automatically call shutdown when java app is terminated, to avoid hung DB connections.

Overrides:

finalize in class java.lang.Object

updateAccessTime

public void updateAccessTime(int id)

Updates the last time a pooled connection was used, so we can manage it better.

Parameters:

dataId - Description of the Parameter