Class PooledConnectionMgr

java.lang.Object

fc.jdbc.ConnectionMgr

fc.jdbc.PooledConnectionMgr

public final class PooledConnectionMgr
extends ConnectionMgr

A pooled connection manager. Connections must be closed when done with, which automatically returns them back to the pool.

Field Summary

Fields

Modifier and Type	Field	Description
static final long	ConnectionTimeoutWarning	If a connection cannot be obtained within this time, then a warning will be logged.
static final int	defaultSize

Constructor Summary

Constructors

Constructor	Description
PooledConnectionMgr(SystemLog log, PropertyMgr props, int size)	Constructs a new connection pool with the specified size.
PooledConnectionMgr(SystemLog log, PropertyMgr props, String prefix, int size)	Constructs a new connection pool with the specified size.
PooledConnectionMgr(PropertyMgr props, int size)	Constructs a new connection pool with the specified size.
PooledConnectionMgr(PropertyMgr props, String prefix, int size)	Constructs a new connection pool with the specified size.
PooledConnectionMgr(String jdbc_url, String jdbc_driver, String jdbc_user, String jdbc_password, String jdbc_catalog, int size)	Constructs a new connection pool with the specified size.

Method Summary

Modifier and Type	Method	Description
Iterator	getCheckoutInfo()	Returns a iterator over a collection of Exception objects, each containing a stack trace for code that has currently checked out a connection from this pool.
List	getHungTransactions(long milliseconds)	Gets a list of connections in the pool such that each connection has a transaction that was started more than the specified milliseconds ago but has not yet been aborted or commited (this is a good way to see if there is a transaction leak somewhere).
static void	main(String[] args)
void	setDebugCheckout(boolean dbg)	Helps to debug connection checkouts.
String	toString()

Methods inherited from class ConnectionMgr

close, getConnection, getDBName, getDriver, getURL, setCatalog

Methods inherited from class Object

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

Field Details

defaultSize

public static final int defaultSize

See Also:

• Constant Field Values

ConnectionTimeoutWarning

public static final long ConnectionTimeoutWarning

If a connection cannot be obtained within this time, then a warning will be logged. The value is in milliseconds.

See Also:

• Constant Field Values

Constructor Details

PooledConnectionMgr

public PooledConnectionMgr(String jdbc_url,
 String jdbc_driver,
 String jdbc_user,
 String jdbc_password,
 String jdbc_catalog,
 int size)
                    throws Exception

Constructs a new connection pool with the specified size.

Throws:

Exception

PooledConnectionMgr

public PooledConnectionMgr(PropertyMgr props,
 int size)
                    throws Exception

Constructs a new connection pool with the specified size. The size is the number of connections that this pool holds.

Throws:

Exception

PooledConnectionMgr

public PooledConnectionMgr(PropertyMgr props,
 String prefix,
 int size)
                    throws Exception

Constructs a new connection pool with the specified size. The size is the number of connections that this pool holds.

Throws:

Exception

PooledConnectionMgr

public PooledConnectionMgr(SystemLog log,
 PropertyMgr props,
 int size)
                    throws Exception

Constructs a new connection pool with the specified size. The size is the number of connections that this pool holds.

Throws:

Exception

PooledConnectionMgr

public PooledConnectionMgr(SystemLog log,
 PropertyMgr props,
 String prefix,
 int size)
                    throws Exception

Constructs a new connection pool with the specified size. The size is the number of connections that this pool holds.

Throws:

Exception

Method Details

setDebugCheckout

public void setDebugCheckout(boolean dbg)

Helps to debug connection checkouts. By default, this is false (since there is a stack trace overhead per connection when debugging is enabled).

Parameters:

dbg - true to enable tracking of checked out connections from this pool. false stops tracking and clears any existing tracking info.

getCheckoutInfo

public Iterator getCheckoutInfo()

Returns a iterator over a collection of Exception objects, each containing a stack trace for code that has currently checked out a connection from this pool. For this to work, make sure that setDebugCheckout(boolean) has first been invoked with true.

getHungTransactions

public List getHungTransactions(long milliseconds)

Gets a list of connections in the pool such that each connection has a transaction that was started more than the specified milliseconds ago but has not yet been aborted or commited (this is a good way to see if there is a transaction leak somewhere).

toString

public String toString()

Overrides:

toString in class ConnectionMgr

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception