Java example source code file (Boxing1.java)

This example Java source code file (Boxing1.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

boolean, boxing1, byte, character, double, error, float, froobie, integer, long, scott, short, string, t4974939

The Boxing1.java Java example source code

/*
 * Copyright (c) 2003, 2004, 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 4869233 4872709 4868735 4921949 4921209 4965701 4934916 4975565 4974939
 * @summary Boxing/unboxing positive unit and regression tests
 * @author gafter
 */

public class Boxing1 {

    static Boolean _Boolean = true;
    static boolean _boolean = _Boolean;

    static Byte _Byte = (byte)3;
    static byte _byte = _Byte;

    static Character _Character = 'a';
    static char _char = _Character;

    static Short _Short = (short)4;
    static short _short = _Short;

    static Integer _Integer = 5;
    static int _int = _Integer;

    static Long _Long = 12L;
    static long _long = _Long;

    static Float _Float = 1.2f;
    static float _float = _Float;

    static Double _Double = 1.34;
    static double _double = _Double;

    public static void main(String[] args) {
        _Double = _Integer + _Integer + 0.0d;
        if (_Double != 10) throw new Error();

        _Integer = 2;
        _float = _Integer;
        if (_float != 2.0f) throw new Error();

        _int = 12;
        _Float = _int + 0.0f;
        if (_Float != 12.0f) throw new Error();

        _Integer = 8;
        _float = (float)_Integer;
        if (_float != 8.0f) throw new Error();

        _int = 9;
        _Float = (Float)(_int + 0.0f);
        if (_Float != 9.0f) throw new Error();

        if (_Boolean) ; else throw new Error();
        if (!_Boolean) throw new Error();

        if (_Integer >= _Long) throw new Error();

        _Character = 'a';
        String s1 = ("_" + _Character + "_").intern();
        if (s1 != "_a_") throw new Error(s1);

        /* assignment operators don't work; see 4921209 */
        if (_Integer++ != 8) throw new Error();
        if (_Integer++ != 9) throw new Error();
        if (++_Integer != 11) throw new Error();
        if ((_Integer += 3) != 14) throw new Error();
        if ((_Integer -= 3) != 11) throw new Error();

        Integer i = 0;
        i = i + 2;
        i += 2;
        if (i != 4) throw new Error();

        int j = 0;
        j += i;
        if (j != 4) throw new Error();

        Integer a[] = new Integer[1];
        a[0] = 3;
        a[0] += 3;
        if (a[0] != 6) throw new Error();

        Froobie x = new Froobie();
        Froobie y = new Froobie();
        x.next = y;
        x.next.i = 4;
        x.next.i += 4;
        if (--x.next.i != 7) throw new Error();
        if (x.next.i-- != 7) throw new Error();
        if (x.next.i != 6) throw new Error();

        boxIndex();
        boxArray();
    }

    static void boxIndex() {
        String[] a = { "hello", "world" };
        Integer i = 0;
        System.out.println(a[i]);
    }

    static void boxArray() {
        Integer[] a2 = { 0, 1, 2, 3 };
        for (int i : a2)
            System.out.println(i);
    }

    static class Froobie {
        Froobie next = null;
        Integer i = 1;
    }

    static class Scott {
        Integer i[];
        Integer j[];
        Integer k;

        int q = i[j[k]]++;
    }

    class T4974939 {
        void f() {
            Byte b = 12;
            Byte c = 'a';

            Short s = 'b';
            Short t = 12;

            Character d = 12;
        }
    }
}