See http://jakarta.apache.org/commons/pool/ for additional and up-to-date information on Commons Pool. Pool 1.3 is largely a bug fix only release. For a complete set of release notes see: http://jakarta.apache.org/commons/pool/release-notes-1.3.html Notable Bugfixes since 1.2: * GenericObjectPools are now a FIFOs. Previously they was documented as such but actually implemented as a LIFOs. * Synchronizations improvements across all implementations. Notable Additions since 1.2: * GenericObjectPool introduced a SoftMinEvictableIdleTimeMillis property which can be used to evict idle objects so long as their eviction would maintain the requested minIdle count. * PoolUtils contains a number of utility methods to decorate pools. * The one dependency on Commons Collections has been removed (okay, technically a deletion) and the only requirement is Java 1.3 or above. Miscellaneous issues: Some of the unit tests may fail spuriously because they are trying to test behavior that depends on the thread scheduler or the garbage collector. If you get a test failure that has "evictor" or "thread" in the test name, please run this test a few times before reporting a bug report for it. If you know how to make one of these unit tests better, please submit a patch. The Apache Jakarta Commons Team, March 2006