test/hotspot/jtreg/gc/TestDisableExplicitGC.java
changeset 47216 71c04702a3d5
parent 40631 ed82623d7831
child 53523 4c5184c56dc2
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/gc/TestDisableExplicitGC.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2015, 2016, 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 TestDisableExplicitGC
+ * @requires vm.opt.DisableExplicitGC == null
+ * @summary Verify GC behavior with DisableExplicitGC flag.
+ * @library /test/lib
+ * @modules java.base/jdk.internal.misc
+ * @modules jdk.management/com.sun.management.internal
+ * @run main/othervm                             -Xlog:gc=debug TestDisableExplicitGC
+ * @run main/othervm/fail -XX:+DisableExplicitGC -Xlog:gc=debug TestDisableExplicitGC
+ * @run main/othervm      -XX:-DisableExplicitGC -Xlog:gc=debug TestDisableExplicitGC
+ */
+import java.lang.management.GarbageCollectorMXBean;
+import java.util.List;
+import static jdk.test.lib.Asserts.*;
+
+public class TestDisableExplicitGC {
+
+    public static void main(String[] args) throws InterruptedException {
+        List<GarbageCollectorMXBean> list = java.lang.management.ManagementFactory.getGarbageCollectorMXBeans();
+        long collectionCountBefore = getCollectionCount(list);
+        System.gc();
+        long collectionCountAfter = getCollectionCount(list);
+        assertLT(collectionCountBefore, collectionCountAfter);
+    }
+
+    private static long getCollectionCount(List<GarbageCollectorMXBean> list) {
+        int collectionCount = 0;
+        for (GarbageCollectorMXBean gcMXBean : list) {
+            collectionCount += gcMXBean.getCollectionCount();
+        }
+        return collectionCount;
+    }
+}