@Test
public void testPurgeUnused() throws IOException {
ReferenceCountedACLCache cache = new ReferenceCountedACLCache();
List<ACL> acl1 = createACL("one");
List<ACL> acl2 = createACL("two");
List<ACL> acl3 = createACL("three");
List<ACL> acl4 = createACL("four");
List<ACL> acl5 = createACL("five");
Long aclId1 = convertACLsNTimes(cache, acl1, 1);
Long aclId2 = convertACLsNTimes(cache, acl2, 2);
Long aclId3 = convertACLsNTimes(cache, acl3, 3);
Long aclId4 = convertACLsNTimes(cache, acl4, 4);
Long aclId5 = convertACLsNTimes(cache, acl5, 5);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
BinaryOutputArchive archive = BinaryOutputArchive.getArchive(baos);
cache.serialize(archive);
BinaryInputArchive inArchive = BinaryInputArchive.getArchive(new ByteArrayInputStream(baos.toByteArray()));
ReferenceCountedACLCache deserializedCache = new ReferenceCountedACLCache();
deserializedCache.deserialize(inArchive);
callAddUsageNTimes(deserializedCache, aclId1, 1);
callAddUsageNTimes(deserializedCache, aclId2, 2);
deserializedCache.purgeUnused();
assertEquals(2, deserializedCache.size());
assertEquals(aclId1, deserializedCache.convertAcls(acl1));
assertEquals(aclId2, deserializedCache.convertAcls(acl2));
assertFalse(acl3.equals(deserializedCache.convertAcls(acl3)));
assertFalse(acl4.equals(deserializedCache.convertAcls(acl4)));
assertFalse(acl5.equals(deserializedCache.convertAcls(acl5)));
}