1 /*

     2  * Copyright (c) 2009, 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 

    27 package sun.util.logging;

    28 

    29 import java.lang.reflect.Field;

    30 import java.security.AccessController;

    31 import java.security.PrivilegedAction;

    32 import java.time.ZonedDateTime;

    33 

    34 /**

    35  * Internal API to support JRE implementation to detect if the java.util.logging

    36  * support is available but with no dependency on the java.util.logging

    37  * classes.  This LoggingSupport class provides several static methods to

    38  * access the java.util.logging functionality that requires the caller

    39  * to ensure that the logging support is {@linkplain #isAvailable available}

    40  * before invoking it.

    41  *

    42  * @see sun.util.logging.PlatformLogger if you want to log messages even

    43  * if the logging support is not available

    44  */

    45 public class LoggingSupport {

    46     private LoggingSupport() { }

    47 

    48     private static final LoggingProxy proxy =

    49         AccessController.doPrivileged(new PrivilegedAction<LoggingProxy>() {

    50             public LoggingProxy run() {

    51                 try {

    52                     // create a LoggingProxyImpl instance when

    53                     // java.util.logging classes exist

    54                     Class<?> c = Class.forName("java.util.logging.LoggingProxyImpl", true, null);

    55                     Field f = c.getDeclaredField("INSTANCE");

    56                     f.setAccessible(true);

    57                     return (LoggingProxy) f.get(null);

    58                 } catch (ClassNotFoundException cnf) {

    59                     return null;

    60                 } catch (NoSuchFieldException e) {

    61                     throw new AssertionError(e);

    62                 } catch (IllegalAccessException e) {

    63                     throw new AssertionError(e);

    64                 }

    65             }});

    66 

    67     /**

    68      * Returns true if java.util.logging support is available.

    69      */

    70     public static boolean isAvailable() {

    71         return proxy != null;

    72     }

    73 

    74     private static void ensureAvailable() {

    75         if (proxy == null)

    76             throw new AssertionError("Should not here");

    77     }

    78 

    79     public static java.util.List<String> getLoggerNames() {

    80         ensureAvailable();

    81         return proxy.getLoggerNames();

    82     }

    83     public static String getLoggerLevel(String loggerName) {

    84         ensureAvailable();

    85         return proxy.getLoggerLevel(loggerName);

    86     }

    87 

    88     public static void setLoggerLevel(String loggerName, String levelName) {

    89         ensureAvailable();

    90         proxy.setLoggerLevel(loggerName, levelName);

    91     }

    92 

    93     public static String getParentLoggerName(String loggerName) {

    94         ensureAvailable();

    95         return proxy.getParentLoggerName(loggerName);

    96     }

    97 

    98     public static Object getLogger(String name) {

    99         ensureAvailable();

   100         return proxy.getLogger(name);

   101     }

   102 

   103     public static Object getLevel(Object logger) {

   104         ensureAvailable();

   105         return proxy.getLevel(logger);

   106     }

   107 

   108     public static void setLevel(Object logger, Object newLevel) {

   109         ensureAvailable();

   110         proxy.setLevel(logger, newLevel);

   111     }

   112 

   113     public static boolean isLoggable(Object logger, Object level) {

   114         ensureAvailable();

   115         return proxy.isLoggable(logger,level);

   116     }

   117 

   118     public static void log(Object logger, Object level, String msg) {

   119         ensureAvailable();

   120         proxy.log(logger, level, msg);

   121     }

   122 

   123     public static void log(Object logger, Object level, String msg, Throwable t) {

   124         ensureAvailable();

   125         proxy.log(logger, level, msg, t);

   126     }

   127 

   128     public static void log(Object logger, Object level, String msg, Object... params) {

   129         ensureAvailable();

   130         proxy.log(logger, level, msg, params);

   131     }

   132 

   133     public static Object parseLevel(String levelName) {

   134         ensureAvailable();

   135         return proxy.parseLevel(levelName);

   136     }

   137 

   138     public static String getLevelName(Object level) {

   139         ensureAvailable();

   140         return proxy.getLevelName(level);

   141     }

   142 

   143     public static int getLevelValue(Object level) {

   144         ensureAvailable();

   145         return proxy.getLevelValue(level);

   146     }

   147 

   148     // Since JDK 9, logging uses java.time to get more precise time stamps.

   149     // It is possible to configure the simple format to print nano seconds (.%1$tN)

   150     // by specifying:

   151     // java.util.logging.SimpleFormatter.format=%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS.%1$tN %1$Tp %2$s%n%4$s: %5$s%6$s%n

   152     // in the logging configuration

   153     private static final String DEFAULT_FORMAT =

   154         "%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS %1$Tp %2$s%n%4$s: %5$s%6$s%n";

   155 

   156     private static final String FORMAT_PROP_KEY = "java.util.logging.SimpleFormatter.format";

   157     public static String getSimpleFormat() {

   158         return getSimpleFormat(true);

   159     }

   160 

   161     // useProxy if true will cause initialization of

   162     // java.util.logging and read its configuration

   163     static String getSimpleFormat(boolean useProxy) {

   164         String format =

   165             AccessController.doPrivileged(

   166                 new PrivilegedAction<String>() {

   167                     public String run() {

   168                         return System.getProperty(FORMAT_PROP_KEY);

   169                     }

   170                 });

   171 

   172         if (useProxy && proxy != null && format == null) {

   173             format = proxy.getProperty(FORMAT_PROP_KEY);

   174         }

   175 

   176         if (format != null) {

   177             try {

   178                 // validate the user-defined format string

   179                 String.format(format, ZonedDateTime.now(), "", "", "", "", "");

   180             } catch (IllegalArgumentException e) {

   181                 // illegal syntax; fall back to the default format

   182                 format = DEFAULT_FORMAT;

   183             }

   184         } else {

   185             format = DEFAULT_FORMAT;

   186         }

   187         return format;

   188     }

   189 

   190 }