1 /* 2 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 package com.oracle.java.testlibrary; 25 26 import java.lang.management.RuntimeMXBean; 27 import java.lang.management.ManagementFactory; 28 import java.util.List; 29 30 /** 31 * This class provides access to the input arguments to the VM. 32 */ 33 public class InputArguments { 34 private static final List<String> args; 35 36 static { 37 RuntimeMXBean runtimeMxBean = ManagementFactory.getRuntimeMXBean(); 38 args = runtimeMxBean.getInputArguments(); 39 } 40 41 /** 42 * Returns true if {@code arg} is an input argument to the VM. 43 * 44 * This is useful for checking boolean flags such as -XX:+UseSerialGC or 45 * -XX:-UsePerfData. 46 * 47 * @param arg The name of the argument. 48 * @return {@code true} if the given argument is an input argument, 49 * otherwise {@code false}. 50 */ 51 public static boolean contains(String arg) { 52 return args.contains(arg); 53 } 54 55 /** 56 * Returns true if {@code prefix} is the start of an input argument to the 57 * VM. 58 * 59 * This is useful for checking if flags describing a quantity, such as 60 * -XX:+MaxMetaspaceSize=100m, is set without having to know the quantity. 61 * To check if the flag -XX:MaxMetaspaceSize is set, use 62 * {@code InputArguments.containsPrefix("-XX:MaxMetaspaceSize")}. 63 * 64 * @param prefix The start of the argument. 65 * @return {@code true} if the given argument is the start of an input 66 * argument, otherwise {@code false}. 67 */ 68 public static boolean containsPrefix(String prefix) { 69 for (String arg : args) { 70 if (arg.startsWith(prefix)) { 71 return true; 72 } 73 } 74 return false; 75 } 76 }