{@inheritDoc} <p> Successive activations of this method examine objects in keyed sub-pools in sequence, cycling through the keys and examining objects in oldest-to-youngest order within the keyed sub-pools.
See Implementation
{@inheritDoc} <p> Successive activations of this method examine objects in keyed sub-pools in sequence, cycling through the keys and examining objects in oldest-to-youngest order within the keyed sub-pools.