1 /*
 2  * Copyright (c) 2022, 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.  Oracle designates this
 8  * particular file as subject to the "Classpath" exception as provided
 9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24  */
25 package jdk.internal.vm;
26 
27 /**
28  * Defines a static method to test if the VM has continuations support.
29  */
30 public class ContinuationSupport {
31     private static final boolean SUPPORTED = isSupported0();
32 
33     private ContinuationSupport() {
34     }
35 
36     /**
37      * Return true if the VM has continuations support.
38      */
39     public static boolean isSupported() {
40         return SUPPORTED;
41     }
42 
43     /**
44      * Ensures that VM has continuations support.
45      * @throws UnsupportedOperationException if not supported
46      */
47     public static void ensureSupported() {
48         if (!isSupported()) {
49             throw new UnsupportedOperationException("VM does not support continuations");
50         }
51     }
52 
53     private static native boolean isSupported0();
54 }