@Test
public void testLiveExpire() throws InterruptedException {

	ExpiringSet<String> expiringSet = new ExpiringSet<String>(2);   // seconds
	assertFalse(expiringSet.contains("hello"));
	assertTrue(expiringSet.contains("hello"));
	int i = 0;
	while (i++ < 1000000) {
		if (!expiringSet.contains("hello")) {
			break;
		}
		Thread.sleep(1);
	}
	assertTrue(expiringSet.contains("hello"));
	assert(i > 1000);
	assert(i < 1000000);
}