test/runtime/CommandLine/OptionsValidation/common/optionsvalidation/JVMOptionsUtils.java

@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * 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.

@@ -25,10 +25,12 @@
 
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.Reader;
+import java.lang.management.GarbageCollectorMXBean;
+import java.lang.management.ManagementFactory;
 import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.LinkedHashMap;

@@ -48,10 +50,13 @@
     private static final StringBuilder finalFailedMessage = new StringBuilder();
 
     /* Used to start the JVM with the same type as current */
     static String VMType;
 
+    /* Used to start the JVM with the same GC type as current */
+    static String GCType;
+
     private static Map<String, JVMOption> optionsAsMap;
 
     static {
         if (Platform.isServer()) {
             VMType = "-server";

@@ -62,10 +67,31 @@
         } else if (Platform.isGraal()) {
             VMType = "-graal";
         } else {
             VMType = null;
         }
+
+        List<GarbageCollectorMXBean> gcMxBeans = ManagementFactory.getGarbageCollectorMXBeans();
+
+        GCType = null;
+
+        for (GarbageCollectorMXBean gcMxBean : gcMxBeans) {
+            switch (gcMxBean.getName()) {
+                case "ConcurrentMarkSweep":
+                    GCType = "-XX:+UseConcMarkSweepGC";
+                    break;
+                case "MarkSweepCompact":
+                    GCType = "-XX:+UseSerialGC";
+                    break;
+                case "PS Scavenge":
+                    GCType = "-XX:+UseParallelGC";
+                    break;
+                case "G1 Old Generation":
+                    GCType = "-XX:+UseG1GC";
+                    break;
+            }
+        }
     }
 
     public static boolean fitsRange(String optionName, BigDecimal number) throws Exception {
         JVMOption option;
         String minRangeString = null;

@@ -151,18 +177,10 @@
      * @param option option
      */
     private static void addNameDependency(JVMOption option) {
         String name = option.getName();
 
-        if (name.startsWith("G1")) {
-            option.addPrepend("-XX:+UseG1GC");
-        }
-
-        if (name.startsWith("CMS")) {
-            option.addPrepend("-XX:+UseConcMarkSweepGC");
-        }
-
         if (name.startsWith("NUMA")) {
             option.addPrepend("-XX:+UseNUMA");
         }
 
         switch (name) {

@@ -441,10 +459,14 @@
         }
 
         if (VMType != null) {
             runJava.add(VMType);
         }
+
+        if (GCType != null) {
+            runJava.add(GCType);
+        }
         runJava.add(PRINT_FLAGS_RANGES);
         runJava.add("-version");
 
         p = ProcessTools.createJavaProcessBuilder(runJava.toArray(new String[0])).start();
 

@@ -532,11 +554,6 @@
      * occurred while reading the data
      */
     public static Map<String, JVMOption> getOptionsWithRangeAsMap(String... additionalArgs) throws Exception {
         return getOptionsWithRangeAsMap(origin -> true, additionalArgs);
     }
-
-    /* Simple method to test that java start-up. Used for testing options. */
-    public static void main(String[] args) {
-        System.out.print("Java start-up!");
-    }
 }