1 /* 2 * Copyright (c) 2012, 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. 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 package java.util; 26 27 import sun.util.logging.PlatformLogger; 28 29 import java.security.AccessController; 30 import java.security.PrivilegedAction; 31 32 /** 33 * Utility class for detecting inadvertent uses of boxing in 34 * {@code java.util} classes. The detection is turned on or off based on 35 * whether the system property {@code org.openjdk.java.util.stream.tripwire} is 36 * considered {@code true} according to {@link Boolean#getBoolean(String)}. 37 * This should normally be turned off for production use. 38 * 39 * @apiNote 40 * Typical usage would be for boxing code to do: 41 * <pre>{@code 42 * if (Tripwire.ENABLED) 43 * Tripwire.trip(getClass(), "{0} calling PrimitiveIterator.OfInt.nextInt()"); 44 * }</pre> 45 * 46 * @since 1.8 47 */ 48 final class Tripwire { 49 private static final String TRIPWIRE_PROPERTY = "org.openjdk.java.util.stream.tripwire"; 50 51 /** Should debugging checks be enabled? */ 52 static final boolean ENABLED = AccessController.doPrivileged( 53 (PrivilegedAction<Boolean>) () -> Boolean.getBoolean(TRIPWIRE_PROPERTY)); 54 55 private Tripwire() { } 56 57 /** 58 * Produces a log warning, using {@code PlatformLogger.getLogger(className)}, 59 * using the supplied message. The class name of {@code trippingClass} will 60 * be used as the first parameter to the message. 61 * 62 * @param trippingClass Name of the class generating the message 63 * @param msg A message format string of the type expected by 64 * {@link PlatformLogger} 65 */ 66 static void trip(Class<?> trippingClass, String msg) { 67 PlatformLogger.getLogger(trippingClass.getName()).warning(msg, trippingClass.getName()); 68 } 69 } 70
