| /* |
| * Copyright (c) 2008, 2018, 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 vm.share; |
| |
| import com.sun.management.HotSpotDiagnosticMXBean; |
| import com.sun.management.VMOption; |
| |
| import java.lang.management.ManagementFactory; |
| import java.util.Objects; |
| |
| public class VMRuntimeEnvUtils { |
| private static HotSpotDiagnosticMXBean DIAGNOSTIC_BEAN |
| = ManagementFactory.getPlatformMXBean(HotSpotDiagnosticMXBean.class); |
| |
| private VMRuntimeEnvUtils() { |
| } |
| |
| public static boolean isJITEnabled() { |
| boolean isJITEnabled = ManagementFactory.getCompilationMXBean() != null; |
| |
| return isJITEnabled; |
| } |
| |
| /** |
| * Returns value of VM option. |
| * |
| * @param name option's name |
| * @return value of option or {@code null}, if option doesn't exist |
| * @throws NullPointerException if name is null |
| * @see HotSpotDiagnosticMXBean#getVMOption(String) |
| */ |
| public static String getVMOption(String name) { |
| Objects.requireNonNull(name); |
| VMOption tmp; |
| try { |
| tmp = DIAGNOSTIC_BEAN.getVMOption(name); |
| } catch (IllegalArgumentException e) { |
| tmp = null; |
| } |
| return (tmp == null ? null : tmp.getValue()); |
| } |
| |
| /** |
| * Returns value of VM option or default value. |
| * |
| * @param name option's name |
| * @param defaultValue default value |
| * @return value of option or {@code defaultValue}, if option doesn't exist |
| * @throws NullPointerException if name is null |
| * @see #getVMOption(String) |
| */ |
| public static String getVMOption(String name, String defaultValue) { |
| String result = getVMOption(name); |
| return result == null ? defaultValue : result; |
| } |
| |
| /** |
| * Returns if a boolean VM option is enabled or not. |
| * |
| * @param name option's name |
| * @return true iff enabled |
| * @throws IllegalArgumentException if naming non-boolean or non-existing option |
| */ |
| public static boolean isVMOptionEnabled(String name) { |
| String isSet = getVMOption(name, "error"); |
| if (isSet.equals("true")) { |
| return true; |
| } else if (isSet.equals("false")) { |
| return false; |
| } |
| throw new IllegalArgumentException(name + " is not a boolean option."); |
| } |
| |
| /** |
| * Sets a specified value for VM option of given name. |
| * |
| * @param name option's name |
| * @param value new value |
| * @throws NullPointerException if name is null |
| * @throws IllegalArgumentException if new value is invalid or if vm option |
| * is not writable. |
| * @see HotSpotDiagnosticMXBean#setVMOption(String, String) |
| */ |
| public static void setVMOption(String name, String value) { |
| Objects.requireNonNull(name); |
| DIAGNOSTIC_BEAN.setVMOption(name, value); |
| } |
| } |