test/java/util/Optional/BasicInt.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 2 along with this work; if not, write to the Free Software Foundation,
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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 {

    }
}