@Test public void of() throws Exception { Assert.assertTrue(OptionalInt.of(42).isPresent()); }
@Test public void ifPresent() throws Exception { OptionalInt.of(42).ifPresent(new IntConsumer() { @Override public void consume(int value) { Assert.assertEquals(42, value); } }); OptionalInt.absent().ifPresent(new IntConsumer() { @Override public void consume(int value) { Assert.fail("ifPresent() on an absent optional should never call its consumer"); } }); }
@Test public void isPresent() throws Exception { Assert.assertTrue(OptionalInt.of(42).isPresent()); Assert.assertFalse(OptionalInt.absent().isPresent()); }
@Test public void ifPresentOrElse() throws Exception { OptionalInt.of(42).ifPresentOrElse(new IntConsumer() { @Override public void consume(int value) { Assert.assertEquals(42, value); } }, new Function() { @Override public void call() { Assert.fail("ifPresent() on an non-absent optional should call its consumer"); } }); OptionalInt.absent().ifPresentOrElse(new IntConsumer() { @Override public void consume(int value) { Assert.fail("ifPresent() on an absent optional should never call its consumer"); } }, new Function() { @Override public void call() { Assert.assertTrue(true); // No-op. This is the expected behaviour. } }); } }
@Test public void get() throws Exception { Assert.assertEquals(42, OptionalInt.of(42).get()); try { OptionalInt.absent().get(); Assert.fail("Invoking get() on an absent optional should raise an exception."); } catch (IllegalStateException expected) { // No-op. This is the expected behaviour. } }