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/* * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */  package sun.util.logging; import java.lang.reflect.Field;import java.security.AccessController;import java.security.PrivilegedAction;import java.util.Date; /** * Internal API to support JRE implementation to detect if the java.util.logging * support is available but with no dependency on the java.util.logging * classes.  This LoggingSupport class provides several static methods to * access the java.util.logging functionality that requires the caller * to ensure that the logging support is {@linkplain #isAvailable available} * before invoking it. * * @see sun.util.logging.PlatformLogger if you want to log messages even * if the logging support is not available */public class LoggingSupport {    private LoggingSupport() { }     private static final LoggingProxy proxy =        AccessController.doPrivileged(new PrivilegedAction<LoggingProxy>() {            public LoggingProxy run() {                try {                    // create a LoggingProxyImpl instance when                    // java.util.logging classes exist                    Class<?> c = Class.forName("java.util.logging.LoggingProxyImpl", true, null);                    Field f = c.getDeclaredField("INSTANCE");                    f.setAccessible(true);                    return (LoggingProxy) f.get(null);                } catch (ClassNotFoundException cnf) {                    return null;                } catch (NoSuchFieldException e) {                    throw new AssertionError(e);                } catch (IllegalAccessException e) {                    throw new AssertionError(e);                }            }});     /**     * Returns true if java.util.logging support is available.     */    public static boolean isAvailable() {        return proxy != null;    }     private static void ensureAvailable() {        if (proxy == null)            throw new AssertionError("Should not here");    }     public static java.util.List<String> getLoggerNames() {        ensureAvailable();        return proxy.getLoggerNames();    }    public static String getLoggerLevel(String loggerName) {        ensureAvailable();        return proxy.getLoggerLevel(loggerName);    }     public static void setLoggerLevel(String loggerName, String levelName) {        ensureAvailable();        proxy.setLoggerLevel(loggerName, levelName);    }     public static String getParentLoggerName(String loggerName) {        ensureAvailable();        return proxy.getParentLoggerName(loggerName);    }     public static Object getLogger(String name) {        ensureAvailable();        return proxy.getLogger(name);    }     public static Object getLevel(Object logger) {        ensureAvailable();        return proxy.getLevel(logger);    }     public static void setLevel(Object logger, Object newLevel) {        ensureAvailable();        proxy.setLevel(logger, newLevel);    }     public static boolean isLoggable(Object logger, Object level) {        ensureAvailable();        return proxy.isLoggable(logger,level);    }     public static void log(Object logger, Object level, String msg) {        ensureAvailable();        proxy.log(logger, level, msg);    }     public static void log(Object logger, Object level, String msg, Throwable t) {        ensureAvailable();        proxy.log(logger, level, msg, t);    }     public static void log(Object logger, Object level, String msg, Object... params) {        ensureAvailable();        proxy.log(logger, level, msg, params);    }     public static Object parseLevel(String levelName) {        ensureAvailable();        return proxy.parseLevel(levelName);    }     public static String getLevelName(Object level) {        ensureAvailable();        return proxy.getLevelName(level);    }     private static final String DEFAULT_FORMAT =        "%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS %1$Tp %2$s%n%4$s: %5$s%6$s%n";     private static final String FORMAT_PROP_KEY = "java.util.logging.SimpleFormatter.format";    public static String getSimpleFormat() {        return getSimpleFormat(true);    }     // useProxy if true will cause initialization of    // java.util.logging and read its configuration    static String getSimpleFormat(boolean useProxy) {        String format =            AccessController.doPrivileged(                new PrivilegedAction<String>() {                    public String run() {                        return System.getProperty(FORMAT_PROP_KEY);                    }                });         if (useProxy && proxy != null && format == null) {            format = proxy.getProperty(FORMAT_PROP_KEY);        }         if (format != null) {            try {                // validate the user-defined format string                String.format(format, new Date(), "", "", "", "", "");            } catch (IllegalArgumentException e) {                // illegal syntax; fall back to the default format                format = DEFAULT_FORMAT;            }        } else {            format = DEFAULT_FORMAT;        }        return format;    } }