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.stream;

    26 

    27 import java.security.AccessController;

    28 import java.security.PrivilegedAction;

    29 

    30 import sun.util.logging.PlatformLogger;

    31 

    32 /**

    33  * Utility class for detecting inadvertent uses of boxing in

    34  * {@code java.util.stream} 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 Sink.OfInt.accept(Integer)");

    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 }