@Test
public void testOverflow() {

  Assert.assertEquals(Long.MAX_VALUE, Callables.overflowSafeAdd(Long.MAX_VALUE, 1));
  Assert.assertEquals(Long.MAX_VALUE, Callables.overflowSafeAdd(Long.MAX_VALUE, Long.MAX_VALUE));
  Assert.assertEquals(3, Callables.overflowSafeAdd(1, 2));
}