8071670: java.util.Optional: please add a way to specify if-else behavior
Reviewed-by: dfuchs, lowasser
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
/* @test
* @summary Basic functional test of OptionalInt
* @author Mike Duigou
* @run testng BasicInt
*/
import java.util.NoSuchElementException;
import java.util.OptionalInt;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.stream.IntStream;
import static org.testng.Assert.*;
import org.testng.annotations.Test;
public class BasicInt {
@Test(groups = "unit")
public void testEmpty() {
OptionalInt empty = OptionalInt.empty();
OptionalInt present = OptionalInt.of(1);
// empty
assertTrue(empty.equals(empty));
assertTrue(empty.equals(OptionalInt.empty()));
assertTrue(!empty.equals(present));
assertTrue(0 == empty.hashCode());
assertTrue(!empty.toString().isEmpty());
assertTrue(!empty.isPresent());
empty.ifPresent(v -> { fail(); });
AtomicBoolean emptyCheck = new AtomicBoolean();
empty.ifPresentOrElse(v -> fail(), () -> emptyCheck.set(true));
assertTrue(emptyCheck.get());
try {
empty.ifPresentOrElse(v -> fail(), () -> { throw new ObscureException(); });
fail();
} catch (ObscureException expected) {
} catch (AssertionError e) {
throw e;
} catch (Throwable t) {
fail();
}
assertEquals(2, empty.orElse(2));
assertEquals(2, empty.orElseGet(()-> 2));
}
@Test(groups = "unit")
public void testIfPresentAndOrElseAndNull() {
OptionalInt empty = OptionalInt.empty();
OptionalInt present = OptionalInt.of(1);
// No NPE
present.ifPresentOrElse(v -> {}, null);
empty.ifPresent(null);
empty.ifPresentOrElse(null, () -> {});
// NPE
try {
present.ifPresent(null);
fail();
} catch (NullPointerException ex) {}
try {
present.ifPresentOrElse(null, () -> {});
fail();
} catch (NullPointerException ex) {}
try {
empty.ifPresentOrElse(v -> {}, null);
fail();
} catch (NullPointerException ex) {}
}
@Test(expectedExceptions=NoSuchElementException.class)
public void testEmptyGet() {
OptionalInt empty = OptionalInt.empty();
int got = empty.getAsInt();
}
@Test(expectedExceptions=NullPointerException.class)
public void testEmptyOrElseGetNull() {
OptionalInt empty = OptionalInt.empty();
int got = empty.orElseGet(null);
}
@Test(expectedExceptions=NullPointerException.class)
public void testEmptyOrElseThrowNull() throws Throwable {
OptionalInt empty = OptionalInt.empty();
int got = empty.orElseThrow(null);
}
@Test(expectedExceptions=ObscureException.class)
public void testEmptyOrElseThrow() throws Exception {
OptionalInt empty = OptionalInt.empty();
int got = empty.orElseThrow(ObscureException::new);
}
@Test(groups = "unit")
public void testPresent() {
OptionalInt empty = OptionalInt.empty();
OptionalInt present = OptionalInt.of(1);
// present
assertTrue(present.equals(present));
assertFalse(present.equals(OptionalInt.of(0)));
assertTrue(present.equals(OptionalInt.of(1)));
assertFalse(present.equals(empty));
assertTrue(Integer.hashCode(1) == present.hashCode());
assertFalse(present.toString().isEmpty());
assertTrue(-1 != present.toString().indexOf(Integer.toString(present.getAsInt()).toString()));
assertEquals(1, present.getAsInt());
AtomicBoolean presentCheck = new AtomicBoolean();
present.ifPresent(v -> presentCheck.set(true));
assertTrue(presentCheck.get());
presentCheck.set(false);
present.ifPresentOrElse(v -> presentCheck.set(true), () -> fail());
assertTrue(presentCheck.get());
try {
present.ifPresent(v -> { throw new ObscureException(); });
fail();
} catch (ObscureException expected) {
} catch (AssertionError e) {
throw e;
} catch (Throwable t) {
fail();
}
try {
present.ifPresentOrElse(v -> { throw new ObscureException(); }, () -> fail());
fail();
} catch (ObscureException expected) {
} catch (AssertionError e) {
throw e;
} catch (Throwable t) {
fail();
}
assertEquals(1, present.orElse(2));
assertEquals(1, present.orElseGet(null));
assertEquals(1, present.orElseGet(()-> 2));
assertEquals(1, present.orElseGet(()-> 3));
assertEquals(1, present.<RuntimeException>orElseThrow(null));
assertEquals(1, present.<RuntimeException>orElseThrow(ObscureException::new));
}
@Test(groups = "unit")
public void testStream() {
{
IntStream s = OptionalInt.empty().stream();
assertFalse(s.isParallel());
int[] es = s.toArray();
assertEquals(es.length, 0);
}
{
IntStream s = OptionalInt.of(42).stream();
assertFalse(s.isParallel());
int[] es = OptionalInt.of(42).stream().toArray();
assertEquals(es.length, 1);
assertEquals(es[0], 42);
}
}
private static class ObscureException extends RuntimeException {
}
}