A call to `sweep()`, although protected by the lock for concurrent calls to `reserve()`, may be concurrent with `remove(Entry)`.
`remove(Entry)` in turn calls `entries.remove(Object)`, so that the concurrent iteration in `sweep()` over `entries` fails with an `ArrayIndexOutOfBoundsException`.
Now using the bulk `entries.removeIf(Predicate)` method in `sweep()`, so that sweeping is atomic with respect to `entries.remove(Object)`.
Fixed other occurrences of manual iteration over CopyOnWriteArrayList that may be concurrent with removals.
Signed-off-by: Simone Bordet <simone.bordet@gmail.com>
115ee1cf39