1 /* 2 * Copyright (c) 2003, 2015, 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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package com.sun.management.internal; 27 28 import java.util.*; 29 import com.sun.management.VMOption; 30 import com.sun.management.VMOption.Origin; 31 import java.security.AccessController; 32 33 /** 34 * Flag class is a helper class for constructing a VMOption. 35 * It has the static methods for getting the Flag objects, each 36 * corresponds to one VMOption. 37 * 38 */ 39 class Flag { 40 private String name; 41 private Object value; 42 private Origin origin; 43 private boolean writeable; 44 private boolean external; 45 Flag(String name, Object value, boolean writeable, boolean external, Origin origin)46 Flag(String name, Object value, boolean writeable, 47 boolean external, Origin origin) { 48 this.name = name; 49 this.value = value == null ? "" : value ; 50 this.origin = origin; 51 this.writeable = writeable; 52 this.external = external; 53 } 54 getValue()55 Object getValue() { 56 return value; 57 } 58 isWriteable()59 boolean isWriteable() { 60 return writeable; 61 } 62 isExternal()63 boolean isExternal() { 64 return external; 65 } 66 getVMOption()67 VMOption getVMOption() { 68 return new VMOption(name, value.toString(), writeable, origin); 69 } 70 getFlag(String name)71 static Flag getFlag(String name) { 72 String[] names = new String[1]; 73 names[0] = name; 74 75 List<Flag> flags = getFlags(names, 1); 76 if (flags.isEmpty()) { 77 return null; 78 } else { 79 // flags should have only one element 80 return flags.get(0); 81 } 82 } 83 getAllFlags()84 static List<Flag> getAllFlags() { 85 int numFlags = getInternalFlagCount(); 86 87 // Get all internal flags with names = null 88 return getFlags(null, numFlags); 89 } 90 getFlags(String[] names, int numFlags)91 private static List<Flag> getFlags(String[] names, int numFlags) { 92 Flag[] flags = new Flag[numFlags]; 93 int count = getFlags(names, flags, numFlags); 94 95 List<Flag> result = new ArrayList<>(); 96 for (Flag f : flags) { 97 if (f != null) { 98 result.add(f); 99 } 100 } 101 return result; 102 } 103 getAllFlagNames()104 private static native String[] getAllFlagNames(); 105 // getFlags sets each element in the given flags array 106 // with a Flag object only if the name is valid and the 107 // type is supported. The flags array may contain null elements. getFlags(String[] names, Flag[] flags, int count)108 private static native int getFlags(String[] names, Flag[] flags, int count); getInternalFlagCount()109 private static native int getInternalFlagCount(); 110 111 // These set* methods are synchronized on the class object 112 // to avoid multiple threads updating the same flag at the same time. setLongValue(String name, long value)113 static synchronized native void setLongValue(String name, long value); setDoubleValue(String name, double value)114 static synchronized native void setDoubleValue(String name, double value); setBooleanValue(String name, boolean value)115 static synchronized native void setBooleanValue(String name, boolean value); setStringValue(String name, String value)116 static synchronized native void setStringValue(String name, String value); 117 118 static { AccessController.doPrivileged( new java.security.PrivilegedAction<Void>() { public Void run() { System.loadLibrary(R); return null; } })119 AccessController.doPrivileged( 120 new java.security.PrivilegedAction<Void>() { 121 public Void run() { 122 System.loadLibrary("management"); 123 return null; 124 } 125 }); initialize()126 initialize(); 127 } initialize()128 private static native void initialize(); 129 } 130