logging.java

JXTA&#8482 is a set of open, generalized peer-to-peer (P2P) protocols that allow any networked devi

/*
 *  Copyright (c) 2001-2004 Sun Microsystems, Inc. All rights reserved.
 *  
 *  The Sun Project JXTA(TM) Software License
 *  
 *  Redistribution and use in source and binary forms, with or without 
 *  modification, are permitted provided that the following conditions are met:
 *  
 *  1. Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *  
 *  2. Redistributions in binary form must reproduce the above copyright notice, 
 *     this list of conditions and the following disclaimer in the documentation 
 *     and/or other materials provided with the distribution.
 *  
 *  3. The end-user documentation included with the redistribution, if any, must 
 *     include the following acknowledgment: "This product includes software 
 *     developed by Sun Microsystems, Inc. for JXTA(TM) technology." 
 *     Alternately, this acknowledgment may appear in the software itself, if 
 *     and wherever such third-party acknowledgments normally appear.
 *  
 *  4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must 
 *     not be used to endorse or promote products derived from this software 
 *     without prior written permission. For written permission, please contact 
 *     Project JXTA at http://www.jxta.org.
 *  
 *  5. Products derived from this software may not be called "JXTA", nor may 
 *     "JXTA" appear in their name, without prior written permission of Sun.
 *  
 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 *  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 
 *  FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SUN 
 *  MICROSYSTEMS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
 *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 
 *  OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 
 *  EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *  
 *  JXTA is a registered trademark of Sun Microsystems, Inc. in the United 
 *  States and other countries.
 *  
 *  Please see the license information page at :
 *  <http://www.jxta.org/project/www/license.html> for instructions on use of 
 *  the license in source files.
 *  
 *  ====================================================================
 *  
 *  This software consists of voluntary contributions made by many individuals 
 *  on behalf of Project JXTA. For more information on Project JXTA, please see 
 *  http://www.jxta.org.
 *  
 *  This license is based on the BSD license adopted by the Apache Foundation. 
 */

package net.jxta.logging;


import java.util.logging.Level;
import java.util.logging.Logger;


/**
 * This class defines constants for JXTA JSE's logging facilities. In this
 * implementation the constants are initialized based upon the value of the
 * Java System property {@code net.jxta.logging.Logging}. This implementation
 * defines all of the public constants as {@code final} which enables the
 * JVM/JIT to optimize out the logging code when appropriately configured.
 * <p/>
 * <p/>Alternate implementations of this class could;
 * <p/>
 * <ul>
 * <li>Initialize the public constants with manifest constants, ie.
 * {@code true} or {@code false} which would allow the Java compiler to
 * optimize out logging code at compile time.</li>
 * <p/>
 * <li>Remove the {@code final} qualifier from the constants and provide
 * additional methods to dynamically set the logging configuration at runtime.
 * </li>
 * </ul>
 *
 * To control logging within applications :
 * 
 * <pre>
 * <code>
 * System.setProperty("net.jxta.logging.Logging", "FINEST");
 * System.setProperty("net.jxta.level", "FINEST");
 * System.setProperty("java.util.logging.config.file", "/home/userhome/logging.properties");
 * </code>
 * </pre>
 *
 * <p/>
 * Sample logging properties :
 * <p/>
 * <pre>
 * <code>
 * # default file output is in user's home directory.
 * java.util.logging.FileHandler.pattern = %h/java%u.log
 * java.util.logging.FileHandler.limit = 50000
 * java.util.logging.FileHandler.count = 1
 * java.util.logging.FileHandler.formatter = java.util.logging.XMLFormatter
 * 
 * # Limit the message that are printed on the console to INFO and above
 * java.util.logging.ConsoleHandler.level = FINEST
 * java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter
 *
 * # Facility specific properties.
 * # Provides extra control for each logger.
 * #
 * # For example, set the net.jxta.impi.pipe.PipeResolver logger to only log SEVERE
 * # messages:
 * net.jxta.impi.pipe.PipeResolver.level = FINEST
 * </code>
 * </pre>
 */
public final class Logging {

    /**
     * Our Logger !
     */
    private final static Logger LOG = Logger.getLogger(Logging.class.getName());

    /**
     * The name of the system property from which we will attempt to read our
     * logging configuration.
     */
    public final static String JXTA_LOGGING_PROPERTY = "net.jxta.logging.Logging";

    /**
     * The default logging level.
     */    
    private final static Level DEFAULT_LOGGING_LEVEL = Level.FINEST;

    /**
     * The logging level for this run.
     */
    public final static Level MIN_SHOW_LEVEL;

    /**
     * Is Level.FINEST enabled?
     */
    public final static boolean SHOW_FINEST;

    /**
     * Is Level.FINER enabled?
     */
    public final static boolean SHOW_FINER;

    /**
     * Is Level.FINE enabled?
     */
    public final static boolean SHOW_FINE;

    /**
     * Is Level.CONFIG enabled?
     */
    public final static boolean SHOW_CONFIG;

    /**
     * Is Level.INFO enabled?
     */
    public final static boolean SHOW_INFO;

    /**
     * Is Level.WARNING enabled?
     */
    public final static boolean SHOW_WARNING;

    /**
     * Is Level.SEVERE enabled?
     */
    public final static boolean SHOW_SEVERE;

    /* Initialize the constants */
    static {
        Level setLevel = DEFAULT_LOGGING_LEVEL;

        try {
            String propertyLevel = System.getProperty(JXTA_LOGGING_PROPERTY);

            if (null != propertyLevel) {
                setLevel = Level.parse(propertyLevel);
            }
        } catch (SecurityException disallowed) {
            LOG.log(Level.WARNING, "Could not read configuration property.", disallowed);
        }

        // Set the default level for the JXTA packages so that everything below
        // inherits our default.
        MIN_SHOW_LEVEL = setLevel;
               
        SHOW_FINEST = MIN_SHOW_LEVEL.intValue() <= Level.FINEST.intValue();
        SHOW_FINER = MIN_SHOW_LEVEL.intValue() <= Level.FINER.intValue();
        SHOW_FINE = MIN_SHOW_LEVEL.intValue() <= Level.FINE.intValue();
        SHOW_CONFIG = MIN_SHOW_LEVEL.intValue() <= Level.CONFIG.intValue();
        SHOW_INFO = MIN_SHOW_LEVEL.intValue() <= Level.INFO.intValue();
        SHOW_WARNING = MIN_SHOW_LEVEL.intValue() <= Level.WARNING.intValue();
        SHOW_SEVERE = MIN_SHOW_LEVEL.intValue() <= Level.SEVERE.intValue();

        if (Logging.SHOW_CONFIG && LOG.isLoggable(Level.CONFIG)) {
            LOG.config("Logging enabled for level : " + MIN_SHOW_LEVEL);
        }
    }

    /**
     * This class is not meant be instantiated.
     */
    private Logging() {}
}