/*

 * Copyright (c) 2017, 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.

 */

package gc.concurrent_phase_control;

/*

 * Utility class that provides verification of expected behavior of

 * the Concurrent GC Phase Control WB API when the current GC does not

 * support phase control.  The invoking test must provide WhiteBox access.

 */

import sun.hotspot.WhiteBox;

public class CheckUnsupported {

    private static final WhiteBox WB = WhiteBox.getWhiteBox();

    public static void check(String gcName) throws Exception {

        // Verify unsupported.

        if (WB.supportsConcurrentGCPhaseControl()) {

            throw new RuntimeException(

                gcName + " unexpectedly supports phase control");

        }

        // Verify phase sequence is empty.

        String[] phases = WB.getConcurrentGCPhases();

        if (phases.length > 0) {

            throw new RuntimeException(

                gcName + " unexpectedly has non-empty phases");

        }

        // Verify IllegalStateException thrown by request attempt.

        boolean illegalStateThrown = false;

        try {

            WB.requestConcurrentGCPhase("UNKNOWN PHASE");

        } catch (IllegalStateException e) {

            // Expected.

            illegalStateThrown = true;

        } catch (Exception e) {

            throw new RuntimeException(

                gcName + ": Unexpected exception when requesting phase: "

                + e.toString());

        }

        if (!illegalStateThrown) {

            throw new RuntimeException(

                gcName + ": No exception when requesting phase");

        }

    }

}