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