@Test
public final void testPercentUsageNeedsNoThread() {    

    int activeThreadCount = Thread.activeCount();
    underTest.setLimit(10);
    underTest.start();
    underTest.increaseUsage(1);
    assertEquals("usage is correct", 10, underTest.getPercentUsage());
    assertEquals("no new thread created without listener or callback",activeThreadCount, Thread.activeCount());
}