RELEASE-NOTES.txt

              Apache Commons Pool 2.0 RELEASE NOTES

The Apache Commons Pool team is pleased to announce the release of Apache
Commons Pool 2.0

Apache Commons Object Pooling Library

This is a major new release that provides significant performance improvements
in high concurrency environments. Pools now provide a mechanism for tracking
objects that have been borrowed from the pool but not returned. There have been
numerous API changes to support these and other new features as well as to
clarify behaviour and improve consistency across the API. This release requires
JDK level 1.6 or above.

The changes to the API are not backwards compatible with Apache Commons Pool
1.x. Therefore, to avoid dependency conflicts, the package name and Maven
co-ordinates have changed as follows:
Package name:      org.apache.commons.pool2
Maven Group ID:    org.apache.commons
Maven Artifact ID: commons-pool2

Changes in this version (relative to Apache Commons Pool 1.6) include:

New features:
o POOL-211:  Add support for proxy wrappers to ObjectPool and KeyedObjectPool. The
             primary advantage of these wrappers is that use of pooled objects is
             prevented after they have been returned to the pool. Thanks to Brad Koehn.

Fixed Bugs:
o POOL-221:  PooledObject.state does not need to be volatile
o POOL-220:  Suppress a FindBugs warning
o POOL-215:  GenericKeyedObjectPool - multiple mutable fields not published safely.
o POOL-214:  GenericObjectPool.evictionPolicy not thread-safe
o POOL-212:  GenericObjectPool allows maxIdle < minIdle
o POOL-207:  GenericKeyedObjectPool.clear() has unnecessary null check of objectDequeue
o POOL-201:  Classes Generic[Keyed]ObjectPoolConfig are generic - but why?
o POOL-200:  GOP/GKOP don't consistently use getters to access fields
o POOL-199:  GOP/GKOP evict() method is not synchronised and is not thread-safe
o POOL-197:  PooledObject: risky init of lastBorrowTime & lastReturnTime
o POOL-196:  PooledObject.getActiveTimeMillis() does not synch. access to lastReturnTime and lastBorrowTime
o POOL-188:  Remove confusing method PoolUtils.ErodingKeyedObjectPool.numIdle(K key). Thanks to sebb.
o POOL-150:  Ensure GKOP.preparePool() throws an exception if no factory has been
             defined.
o POOL-134:  Add the ability to specify a per call wait time when borrowing an object.
o POOL-121:  Provide a name for the eviction timer thread.
o POOL-173:  Reduce duplication in configuration code.
o POOL-178:  Re-factor common code into common base classes.
o POOL-100:  Allow custom eviction policies to be defined.

Changes:
o POOL-229:  Added abandoned object removal (moved from DBCP) to GenericObjectPool.
o POOL-217:  Use an IODH for PoolUtils.MIN_IDLE_TIMER Thanks to sebb.
o POOL-216:  GenericKeyedObjectPool.ensureMinIdle(K) does not need to check getMinIdlePerKey().
o POOL-194:  Replace synchronized blocks in PoolUtils with Read/Write locks.
o POOL-83:   Support Java 1.5 Generics.
o POOL-186:  Developer documentation and examples have to be updated once the 2.0 repackaging has been done
o            Switch GOP to use a pooling mechanism based on java.util.concurrent and a
             LinkedBlockingQueue implementation from Apache Harmony (originally by Doug
             Lea and the JSR-166 expert group).
o            Make deprecated protected attributes private, requiring that access is via
             the appropriate getters.
o            Code clean-up. Add missing @Override annotations, remove unused code,
             remove deprecated code and unnecessary code.
o            Introduce an Enum (WhenExhaustedAction) to control pool behaviour when no
             more objects are available to allocate.
o            Remove WhenExhuastedAction.GROW since it is equivalent to
             WhenExhuastedAction.FAIL with a maxActive value of Integer.MAX_VALUE.
o POOL-155:  Guard against multiple returns of the same object to the pool and ensure
             that only objects borrowed from the pool are returned to it.
o            Remove setFactory() method from GOP.
o POOL-172:  Expose GOP and GKOP attributes via JMX.
o POOL-98:   Add additional attributes (also accessible via JMX) for monitoring.
o            Change meaning of zero for maxWait to a maximum wait of zero milliseconds
             rather than the unexpected infinite wait.


For complete information on Apache Commons Pool, including instructions on how to submit bug reports,
patches, or suggestions for improvement, see the Apache Commons Pool website:

http://commons.apache.org/proper/commons-pool/