BasicInt.java

/*
 * Copyright (c) 2013, 2018, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/* @test
 * @bug 8195649
 * @summary Basic functional test of OptionalInt
 * @author Mike Duigou
 * @build ObscureException
 * @run testng BasicInt
 */

import java.util.NoSuchElementException;
import java.util.OptionalInt;
import java.util.concurrent.atomic.AtomicBoolean;

import static org.testng.Assert.*;
import org.testng.annotations.Test;

public class BasicInt {

    static final int INTVAL = 33_550_336;
    static final int UNEXPECTED = 0xCAFEBABE;

    /**
     * Checks a block of assertions over an empty OptionalInt.
     */
    void checkEmpty(OptionalInt empty) {
        assertTrue(empty.equals(OptionalInt.empty()));
        assertTrue(OptionalInt.empty().equals(empty));
        assertFalse(empty.equals(OptionalInt.of(UNEXPECTED)));
        assertFalse(OptionalInt.of(UNEXPECTED).equals(empty));
        assertFalse(empty.equals("unexpected"));

        assertFalse(empty.isPresent());
        assertTrue(empty.isEmpty());
        assertEquals(empty.hashCode(), 0);
        assertEquals(empty.orElse(UNEXPECTED), UNEXPECTED);
        assertEquals(empty.orElseGet(() -> UNEXPECTED), UNEXPECTED);

        assertThrows(NoSuchElementException.class, () -> empty.getAsInt());
        assertThrows(NoSuchElementException.class, () -> empty.orElseThrow());
        assertThrows(ObscureException.class,       () -> empty.orElseThrow(ObscureException::new));

        var b = new AtomicBoolean();
        empty.ifPresent(s -> b.set(true));
        assertFalse(b.get());

        var b1 = new AtomicBoolean(false);
        var b2 = new AtomicBoolean(false);
        empty.ifPresentOrElse(s -> b1.set(true), () -> b2.set(true));
        assertFalse(b1.get());
        assertTrue(b2.get());

        assertEquals(empty.toString(), "OptionalInt.empty");
    }

    /**
     * Checks a block of assertions over an OptionalInt that is expected to
     * have a particular value present.
     */
    void checkPresent(OptionalInt opt, int expected) {
        assertFalse(opt.equals(OptionalInt.empty()));
        assertFalse(OptionalInt.empty().equals(opt));
        assertTrue(opt.equals(OptionalInt.of(expected)));
        assertTrue(OptionalInt.of(expected).equals(opt));
        assertFalse(opt.equals(OptionalInt.of(UNEXPECTED)));
        assertFalse(OptionalInt.of(UNEXPECTED).equals(opt));
        assertFalse(opt.equals("unexpected"));

        assertTrue(opt.isPresent());
        assertFalse(opt.isEmpty());
        assertEquals(opt.hashCode(), Integer.hashCode(expected));
        assertEquals(opt.orElse(UNEXPECTED), expected);
        assertEquals(opt.orElseGet(() -> UNEXPECTED), expected);

        assertEquals(opt.getAsInt(), expected);
        assertEquals(opt.orElseThrow(), expected);
        assertEquals(opt.orElseThrow(ObscureException::new), expected);

        var b = new AtomicBoolean(false);
        opt.ifPresent(s -> b.set(true));
        assertTrue(b.get());

        var b1 = new AtomicBoolean(false);
        var b2 = new AtomicBoolean(false);
        opt.ifPresentOrElse(s -> b1.set(true), () -> b2.set(true));
        assertTrue(b1.get());
        assertFalse(b2.get());

        assertEquals(opt.toString(), "OptionalInt[" + expected + "]");
    }

    @Test(groups = "unit")
    public void testEmpty() {
        checkEmpty(OptionalInt.empty());
    }

    @Test(groups = "unit")
    public void testPresent() {
        checkPresent(OptionalInt.of(INTVAL), INTVAL);
    }

    @Test(groups = "unit")
    public void testStreamEmpty() {
        assertEquals(OptionalInt.empty().stream().toArray(), new int[] { });
    }

    @Test(groups = "unit")
    public void testStreamPresent() {
        assertEquals(OptionalInt.of(INTVAL).stream().toArray(), new int[] { INTVAL });
    }
}