org.qbroker.persister

Class PersisterPool

java.lang.Object

org.qbroker.persister.Persister

org.qbroker.persister.PersisterPool

All Implemented Interfaces:

java.lang.Runnable, MessagePersister

public class PersisterPool
extends Persister
implements java.lang.Runnable

PersisterPool listens to an XQueue for requests carried by ObjectMessages. Once there is a new request, it will check the URI and the type to figure out the details of the request. If the request is to ask for a persister, it first looks up the classname of the implementation based on the URI and the given properties. Then PersisterPool tries to check out the pool of the classname from the cache. If there exists the persister pool for the implementation, it just checks out a new instance of the persister with the given properties. Otherwise, PersisterPool will create a new pool for the classname and checks out a new instance of the persister from it. It then starts up a new thread on the persister and returns the thread back. The requester is supposed to monitor the status of the thread in order to tell the status of the persister. The requester is also able to control the persister via the associated transmit queue. PersisterPool will frequently monitor the status of each active persisters in every heartbeat. If any one of them is stopped or closed, PersisterPool will checkin the persister and clean up the cache. If the request is to return the used thread, it will check in both the thread and the persister.

URI is used to identify the destinations. PersisterPool parses the URI string and creates a Map with all properties from the key-value pairs specified in the query-string. Therefore, please carefully define them in the query-string of the URI. PersisterPool also allows the default properties defined for each implementations. If any of the default properties is missing in the URI, PersisterPool will copy it to the property Map before the instantiation of the MessagePersister.

Author:

yannanlu@yahoo.com

Field Summary

Fields inherited from class org.qbroker.persister.Persister

capacity, displayMask, linkName, maxRetry, operation, partition, pauseTime, propertyName, repeatPeriod, standbyTime, status, timeout, tolerance, uri, waitTime, xaMode

Fields inherited from interface org.qbroker.persister.MessagePersister

PSTR_CLOSED, PSTR_DISABLED, PSTR_PAUSE, PSTR_READY, PSTR_RETRYING, PSTR_RUNNING, PSTR_STANDBY, PSTR_STOPPED

Constructor Summary

Constructors

Constructor and Description
PersisterPool(java.util.Map props)

Method Summary

Modifier and Type	Method and Description
void	close() closes all opened resources
protected void	finalize()
static java.lang.String	lookup(java.lang.String uriStr, java.util.Map<java.lang.String,java.lang.Object> props) returns className and fill up parameters to props or null on failure
static java.lang.String	mapURI(java.lang.String uri, java.util.Map props) It is a utility to parse URI and update property Map to set some mandatory properties, like ClassName, for persisters.
void	persist(XQueue xq, int baseTime) gets all the JMS messages from the XQueue and delivers them to their destinations.
void	run() runs the current thread to persist messages on a given XQueue.
static int	split(java.lang.String s, java.lang.String e, java.lang.String text, java.util.Map<java.lang.String,java.lang.Object> attr) splits the text with the pair delimiter of s and and key delimiter of e and fills up the key-value pair to Map

Methods inherited from class org.qbroker.persister.Persister

getCapacity, getLinkName, getName, getOperation, getStatus, getXAMode, isStopped, keepRunning, resetStatus, setStatus

Methods inherited from class java.lang.Object

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

Constructor Detail

PersisterPool

public PersisterPool(java.util.Map props)

Method Detail

persist

public void persist(XQueue xq,
                    int baseTime)

Description copied from interface: MessagePersister

gets all the JMS messages from the XQueue and delivers them to their destinations. In case of failure, it should keep retry with the sleepTime in milliseconds.

Specified by:

persist in interface MessagePersister

Specified by:

persist in class Persister

run

public void run()

runs the current thread to persist messages on a given XQueue. If it exits abnormally, it will check-in the persister and set the asset status to PSTR_CLOSED. Otherwise, the status will be set to PSTR_STOPPED to indicate the asset needs to be cleaned up.

Specified by:

run in interface java.lang.Runnable

lookup

public static java.lang.String lookup(java.lang.String uriStr,
                                      java.util.Map<java.lang.String,java.lang.Object> props)

returns className and fill up parameters to props or null on failure

split

public static int split(java.lang.String s,
                        java.lang.String e,
                        java.lang.String text,
                        java.util.Map<java.lang.String,java.lang.Object> attr)

splits the text with the pair delimiter of s and and key delimiter of e and fills up the key-value pair to Map

mapURI

public static java.lang.String mapURI(java.lang.String uri,
                                      java.util.Map props)
                               throws java.net.URISyntaxException

It is a utility to parse URI and update property Map to set some mandatory properties, like ClassName, for persisters.

Throws:

java.net.URISyntaxException

close

public void close()

Description copied from interface: MessagePersister

closes all opened resources

Specified by:

close in interface MessagePersister

Specified by:

close in class Persister

finalize

protected void finalize()

Overrides:

finalize in class java.lang.Object