diff -r 009de2b033fc -r 0c48231c5c84 test/testlibrary_tests/whitebox/vm_flags/VmFlagTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/testlibrary_tests/whitebox/vm_flags/VmFlagTest.java	Fri May 30 17:20:48 2014 +0400
@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2014, 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.
+ */
+
+import java.util.Objects;
+import java.util.function.BiConsumer;
+import java.util.function.Function;
+import sun.hotspot.WhiteBox;
+import sun.management.*;
+import com.sun.management.*;
+import com.oracle.java.testlibrary.*;
+
+public final class VmFlagTest<T> {
+    public static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();
+
+    private static final String NONEXISTENT_FLAG = "NonexistentFlag";
+    private final String flagName;
+    private final BiConsumer<T, T> test;
+    private final BiConsumer<String, T> set;
+    private final Function<String, T> get;
+
+    protected VmFlagTest(String flagName, BiConsumer<String, T> set,
+            Function<String, T> get, boolean isPositive) {
+        this.flagName = flagName;
+        this.set = set;
+        this.get = get;
+        if (isPositive) {
+            test = this::testPositive;
+        } else {
+            test = this::testNegative;
+        }
+    }
+
+    private void setNewValue(T value) {
+        set.accept(flagName, value);
+    }
+
+    private T getValue() {
+        T t = get.apply(flagName);
+        System.out.println("T = " + t);
+        return t;
+    }
+
+    protected static <T> void runTest(String existentFlag, T[] tests,
+            BiConsumer<String, T> set, Function<String, T> get) {
+        runTest(existentFlag, tests, tests, set, get);
+    }
+
+    protected static <T> void runTest(String existentFlag, T[] tests,
+            T[] results, BiConsumer<String, T> set, Function<String, T> get) {
+        if (existentFlag != null) {
+            new VmFlagTest(existentFlag, set, get, true).test(tests, results);
+        }
+        new VmFlagTest(NONEXISTENT_FLAG, set, get, false).test(tests, results);
+    }
+
+    public final void test(T[] tests, T[] results) {
+        Asserts.assertEQ(tests.length, results.length, "[TESTBUG] tests.length != results.length");
+        for (int i = 0, n = tests.length ; i < n; ++i) {
+            test.accept(tests[i], results[i]);
+        }
+    }
+
+    protected String getVMOptionAsString() {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption(flagName);
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        return tmp == null ? null : tmp.getValue();
+    }
+
+    private void testPositive(T value, T expected) {
+        Asserts.assertEQ(getVMOptionAsString(), asString(getValue()));
+        setNewValue(value);
+        String newValue = getVMOptionAsString();
+        Asserts.assertEQ(newValue, asString(expected));
+        Asserts.assertEQ(getVMOptionAsString(), asString(getValue()));
+    }
+
+    private void testNegative(T value, T expected) {
+        String oldValue = getVMOptionAsString();
+        Asserts.assertEQ(oldValue, asString(getValue()));
+        setNewValue(value);
+        String newValue = getVMOptionAsString();
+        Asserts.assertEQ(oldValue, newValue);
+    }
+
+    private String asString(Object value) {
+        return value == null ? null : "" + value;
+    }
+}
+