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diff --git a/test/lib/jdk/test/lib/management/DynamicVMOption.java b/test/lib/jdk/test/lib/management/DynamicVMOption.java
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+/*
+ * Copyright (c) 2014, 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.
+ */
+
+package jdk.test.lib.management;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import java.lang.management.ManagementFactory;
+
+/**
+ * A utility class to work with VM options which could be altered during
+ * execution.
+ *
+ * This class is a wrapper around {@code com.sun.management.VMOption}.
+ * It provides more convenient interface to read/write the values.
+ *
+ */
+public class DynamicVMOption {
+
+ private final HotSpotDiagnosticMXBean mxBean;
+
+ /**
+ * VM option name, like "MinHeapFreeRatio".
+ */
+ public final String name;
+
+ /**
+ * Creates an instance of DynamicVMOption.
+ *
+ * @param name the VM option name
+ */
+ public DynamicVMOption(String name) {
+ this.name = name;
+ mxBean = ManagementFactory.getPlatformMXBean(HotSpotDiagnosticMXBean.class);
+ }
+
+ /**
+ * Sets a new value for the option.
+ * Trying to set not applicable value will cause IllegalArgumentException.
+ * Behavior with null is undefined, most likely NPE will be thrown.
+ *
+ * @param newValue the value to be set
+ * @see #getValue()
+ * @throws IllegalArgumentException if newValue is not applicable to the option
+ */
+ public final void setValue(String newValue) {
+ mxBean.setVMOption(name, newValue);
+ }
+
+ /**
+ * Returns the value of option.
+ *
+ * @return the current option value
+ * @see #setValue(java.lang.String)
+ */
+ public final String getValue() {
+ return mxBean.getVMOption(name).getValue();
+ }
+
+ /**
+ * Returns true, if option is writable, false otherwise.
+ *
+ * @return true, if option is writable, false otherwise
+ */
+ public final boolean isWriteable() {
+ return mxBean.getVMOption(name).isWriteable();
+ }
+
+ /**
+ * Checks if the given value is applicable for the option.
+ *
+ * This method tries to set the option to the new value. If no exception
+ * has been thrown the value is treated as valid.
+ *
+ * Calling this method will not change the option value. After an attempt
+ * to set a new value, the option will be restored to its previous value.
+ *
+ * @param value the value to verify
+ * @return true if option could be set to the given value
+ */
+ public boolean isValidValue(String value) {
+ boolean isValid = true;
+ String oldValue = getValue();
+ try {
+ setValue(value);
+ } catch (NullPointerException e) {
+ if (value == null) {
+ isValid = false;
+ }
+ } catch (IllegalArgumentException e) {
+ isValid = false;
+ } finally {
+ setValue(oldValue);
+ }
+ return isValid;
+ }
+
+ /**
+ * Returns the value of the given VM option as String.
+ *
+ * This is a simple shortcut for {@code new DynamicVMOption(name).getValue()}
+ *
+ * @param name the name of VM option
+ * @return value as a string
+ * @see #getValue()
+ */
+ public static String getString(String name) {
+ return new DynamicVMOption(name).getValue();
+ }
+
+ /**
+ * Returns the value of the given option as int.
+ *
+ * @param name the name of VM option
+ * @return value parsed as integer
+ * @see #getString(java.lang.String)
+ *
+ */
+ public static int getInt(String name) {
+ return Integer.parseInt(getString(name));
+ }
+
+ /**
+ * Sets the VM option to a new value.
+ *
+ * This is a simple shortcut for {@code new DynamicVMOption(name).setValue(value)}
+ *
+ * @param name the name of VM option
+ * @param value the value to be set
+ * @see #setValue(java.lang.String)
+ */
+ public static void setString(String name, String value) {
+ new DynamicVMOption(name).setValue(value);
+ }
+
+ /**
+ * Sets the VM option value to a new integer value.
+ *
+ * @param name the name of VM option
+ * @param value the integer value to be set
+ * @see #setString(java.lang.String, java.lang.String)
+ */
+ public static void setInt(String name, int value) {
+ new DynamicVMOption(name).setValue(Integer.toString(value));
+ }
+
+}