StrictMaxPool does not maintain a correct "inUse" count leading to incorrect reporting of "AvailableCount"

The org.jboss.ejb3.test.stateless.unit.MetricsUnitTestCase shows a failure w.r.t the "AvailableCount" of a bean marked with StrictMaxPool.

The StrictMaxPool internally implements the getAvailableCount() as follows:

public int getAvailableCount()

The "inUse" count is handled incorrectly in the discard and remove method of this pool leading to that count reaching a negative value. Ultimately, this leads to incorrect available count being reported.

When an exception occurs, the bean is discarded from the pool. This leads to a call on discard method of the StrictMaxPool which decrements the inUse count and then calls the remove method which again decrements the inUse count for the same bean context.