iignatyev@6963: /*
iignatyev@6963:  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
iignatyev@6963:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
iignatyev@6963:  *
iignatyev@6963:  * This code is free software; you can redistribute it and/or modify it
iignatyev@6963:  * under the terms of the GNU General Public License version 2 only, as
iignatyev@6963:  * published by the Free Software Foundation.
iignatyev@6963:  *
iignatyev@6963:  * This code is distributed in the hope that it will be useful, but WITHOUT
iignatyev@6963:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
iignatyev@6963:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
iignatyev@6963:  * version 2 for more details (a copy is included in the LICENSE file that
iignatyev@6963:  * accompanied this code).
iignatyev@6963:  *
iignatyev@6963:  * You should have received a copy of the GNU General Public License version
iignatyev@6963:  * 2 along with this work; if not, write to the Free Software Foundation,
iignatyev@6963:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
iignatyev@6963:  *
iignatyev@6963:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
iignatyev@6963:  * or visit www.oracle.com if you need additional information or have any
iignatyev@6963:  * questions.
iignatyev@6963:  */
iignatyev@6963: 
iignatyev@6963: import java.util.Objects;
iignatyev@6963: import java.util.function.BiConsumer;
iignatyev@6963: import java.util.function.Function;
iignatyev@6963: import sun.hotspot.WhiteBox;
iignatyev@6963: import sun.management.*;
iignatyev@6963: import com.sun.management.*;
iignatyev@6963: import com.oracle.java.testlibrary.*;
iignatyev@6963: 
iignatyev@6963: public final class VmFlagTest<T> {
iignatyev@6963:     public static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();
iignatyev@6963: 
iignatyev@6963:     private static final String NONEXISTENT_FLAG = "NonexistentFlag";
iignatyev@6963:     private final String flagName;
iignatyev@6963:     private final BiConsumer<T, T> test;
iignatyev@6963:     private final BiConsumer<String, T> set;
iignatyev@6963:     private final Function<String, T> get;
iignatyev@6963: 
iignatyev@6963:     protected VmFlagTest(String flagName, BiConsumer<String, T> set,
iignatyev@6963:             Function<String, T> get, boolean isPositive) {
iignatyev@6963:         this.flagName = flagName;
iignatyev@6963:         this.set = set;
iignatyev@6963:         this.get = get;
iignatyev@6963:         if (isPositive) {
iignatyev@6963:             test = this::testPositive;
iignatyev@6963:         } else {
iignatyev@6963:             test = this::testNegative;
iignatyev@6963:         }
iignatyev@6963:     }
iignatyev@6963: 
iignatyev@6963:     private void setNewValue(T value) {
iignatyev@6963:         set.accept(flagName, value);
iignatyev@6963:     }
iignatyev@6963: 
iignatyev@6963:     private T getValue() {
iignatyev@6963:         T t = get.apply(flagName);
iignatyev@6963:         System.out.println("T = " + t);
iignatyev@6963:         return t;
iignatyev@6963:     }
iignatyev@6963: 
iignatyev@6963:     protected static <T> void runTest(String existentFlag, T[] tests,
iignatyev@6963:             BiConsumer<String, T> set, Function<String, T> get) {
iignatyev@6963:         runTest(existentFlag, tests, tests, set, get);
iignatyev@6963:     }
iignatyev@6963: 
iignatyev@6963:     protected static <T> void runTest(String existentFlag, T[] tests,
iignatyev@6963:             T[] results, BiConsumer<String, T> set, Function<String, T> get) {
iignatyev@6963:         if (existentFlag != null) {
iignatyev@6963:             new VmFlagTest(existentFlag, set, get, true).test(tests, results);
iignatyev@6963:         }
iignatyev@6963:         new VmFlagTest(NONEXISTENT_FLAG, set, get, false).test(tests, results);
iignatyev@6963:     }
iignatyev@6963: 
iignatyev@6963:     public final void test(T[] tests, T[] results) {
iignatyev@6963:         Asserts.assertEQ(tests.length, results.length, "[TESTBUG] tests.length != results.length");
iignatyev@6963:         for (int i = 0, n = tests.length ; i < n; ++i) {
iignatyev@6963:             test.accept(tests[i], results[i]);
iignatyev@6963:         }
iignatyev@6963:     }
iignatyev@6963: 
iignatyev@6963:     protected String getVMOptionAsString() {
iignatyev@6963:         HotSpotDiagnosticMXBean diagnostic
iignatyev@6963:                 = ManagementFactoryHelper.getDiagnosticMXBean();
iignatyev@6963:         VMOption tmp;
iignatyev@6963:         try {
iignatyev@6963:             tmp = diagnostic.getVMOption(flagName);
iignatyev@6963:         } catch (IllegalArgumentException e) {
iignatyev@6963:             tmp = null;
iignatyev@6963:         }
iignatyev@6963:         return tmp == null ? null : tmp.getValue();
iignatyev@6963:     }
iignatyev@6963: 
iignatyev@6963:     private void testPositive(T value, T expected) {
iignatyev@6963:         Asserts.assertEQ(getVMOptionAsString(), asString(getValue()));
iignatyev@6963:         setNewValue(value);
iignatyev@6963:         String newValue = getVMOptionAsString();
iignatyev@6963:         Asserts.assertEQ(newValue, asString(expected));
iignatyev@6963:         Asserts.assertEQ(getVMOptionAsString(), asString(getValue()));
iignatyev@6963:     }
iignatyev@6963: 
iignatyev@6963:     private void testNegative(T value, T expected) {
iignatyev@6963:         String oldValue = getVMOptionAsString();
iignatyev@6963:         Asserts.assertEQ(oldValue, asString(getValue()));
iignatyev@6963:         setNewValue(value);
iignatyev@6963:         String newValue = getVMOptionAsString();
iignatyev@6963:         Asserts.assertEQ(oldValue, newValue);
iignatyev@6963:     }
iignatyev@6963: 
iignatyev@6963:     private String asString(Object value) {
iignatyev@6963:         return value == null ? null : "" + value;
iignatyev@6963:     }
iignatyev@6963: }
iignatyev@6963: