1 /*

     2  * Copyright (c) 2017, 2019, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  */

    23 

    24 /*

    25  * @test

    26  * @bug 8231827

    27  * @summary Testing pattern matching against the null constant

    28  * @compile --enable-preview -source ${jdk.version} NullsInPatterns.java

    29  * @run main/othervm --enable-preview NullsInPatterns

    30  */

    31 import java.util.List;

    32 

    33 public class NullsInPatterns {

    34 

    35     public static void main(String[] args) {

    36         if (null instanceof List t) {

    37             throw new AssertionError("broken");

    38         } else {

    39             System.out.println("null does not match List type pattern");

    40         }

    41         //reifiable types not allowed in type test patterns in instanceof:

    42 //        if (null instanceof List<Integer> l) {

    43 //            throw new AssertionError("broken");

    44 //        } else {

    45 //            System.out.println("null does not match List<Integer> type pattern");

    46 //        }

    47         if (null instanceof List<?> l) {

    48             throw new AssertionError("broken");

    49         } else {

    50             System.out.println("null does not match List<?> type pattern");

    51         }

    52     }

    53 }