org.logicalcobwebs.proxool
Class Prototyper

java.lang.Object
  org.logicalcobwebs.proxool.Prototyper

public class Prototyper
extends java.lang.Object

Responsible for prototyping connections for all pools

Since:

Proxool 0.8

Version:

$Revision: 1.12 $, $Date: 2006/01/16 23:10:41 $

Author:

bill, $Author: billhorsman $ (current maintainer)

Field Summary

private boolean	cancel Calling cancel will set this to true and stop all current prototyping immediately
private ConnectionBuilderIF	connectionBuilder The builder that will create *real* connections for us.
private long	connectionCount
private ConnectionPool	connectionPool
private int	connectionsBeingMade The number of connections currently being made (actually in progress)
private java.lang.Object	lock
private Log	log
private long	nextConnectionId This allows us to have a unique ID for each connection
private boolean	sweepNeeded

Constructor Summary

Prototyper(ConnectionPool connectionPool)

Method Summary

protected ProxyConnection	buildConnection(int status, java.lang.String creator) Build a new connection
void	cancel() Cancel all current prototyping
protected void	checkSimultaneousBuildThrottle() Checks whether we are currently already building too many connections
protected void	connectionRemoved() This needs to be called _everytime_ a connection is removed.
java.lang.String	getAlias() The alias of the pool we are prototyping for
long	getConnectionCount() The total number of connections, including those being built right now
private ConnectionPoolDefinitionIF	getDefinition() Utility method
protected boolean	isSweepNeeded()
boolean	quickRefuse() Give a quick answer to whether we should attempt to build a connection.
protected boolean	sweep() Trigger prototyping immediately
protected void	triggerSweep()

Methods inherited from class java.lang.Object

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

Field Detail

connectionPool

private ConnectionPool connectionPool

log

private Log log

connectionCount

private long connectionCount

lock

private final java.lang.Object lock

sweepNeeded

private boolean sweepNeeded

nextConnectionId

private long nextConnectionId

This allows us to have a unique ID for each connection

cancel

private boolean cancel

Calling cancel will set this to true and stop all current prototyping immediately

connectionsBeingMade

private int connectionsBeingMade

The number of connections currently being made (actually in progress)

connectionBuilder

private ConnectionBuilderIF connectionBuilder

The builder that will create *real* connections for us. Currently initialized to the default implementation until we fully support pluggable ConnectionBuilders

Constructor Detail

Prototyper

public Prototyper(ConnectionPool connectionPool)

Method Detail

isSweepNeeded

protected boolean isSweepNeeded()

triggerSweep

protected void triggerSweep()

sweep

protected boolean sweep()

Trigger prototyping immediately

Returns:

true if something was prototyped

buildConnection

protected ProxyConnection buildConnection(int status,
                                          java.lang.String creator)
                                   throws java.sql.SQLException,
                                          ProxoolException

Build a new connection

Parameters:

status - the initial status it will be created as (this allows us to create it as ACTIVE and avoid another thread grabbing it before we can)

creator - for log audit

Returns:

the new connection

Throws:

java.sql.SQLException

ProxoolException

connectionRemoved

protected void connectionRemoved()

This needs to be called _everytime_ a connection is removed.

checkSimultaneousBuildThrottle

protected void checkSimultaneousBuildThrottle()
                                       throws java.sql.SQLException

Checks whether we are currently already building too many connections

Throws:

java.sql.SQLException - if the throttle has been reached

getConnectionCount

public long getConnectionCount()

The total number of connections, including those being built right now

Returns:

connectionCount;

getDefinition

private ConnectionPoolDefinitionIF getDefinition()

Utility method

Returns:

definition

cancel

public void cancel()

Cancel all current prototyping

getAlias

public java.lang.String getAlias()

The alias of the pool we are prototyping for

Returns:

alias

quickRefuse

public boolean quickRefuse()

Give a quick answer to whether we should attempt to build a connection. This can be quicker if we are massively overloaded rather than cycling through each connection in the pool to see if it's free

Returns:

true if it's okay to attempt to get a connection, false if we should give up now. Just because this method returns true it doesn't guarantee that one will be available. There is a slight risk that we might tell the client to give up when a connection could become available in the next few milliseconds but our policy is to refuse connections quickly when overloaded.