defaultlog.java

来自「JfreeChart 常用图表例子」· Java 代码 · 共 118 行

/* ========================================================================
 * JCommon : a free general purpose class library for the Java(tm) platform
 * ========================================================================
 *
 * (C) Copyright 2000-2004, by Object Refinery Limited and Contributors.
 * 
 * Project Info:  http://www.jfree.org/jcommon/index.html
 *
 * This library is free software; you can redistribute it and/or modify it under the terms
 * of the GNU Lesser General Public License as published by the Free Software Foundation;
 * either version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
 * in the United States and other countries.]
 * 
 * ---------------
 * DefaultLog.java
 * ---------------
 * (C) Copyright 2004, by Object Refinery Limited.
 *
 * Original Author:  Thomas Morgner;
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *
 * $Id: DefaultLog.java,v 1.3 2005/06/01 14:12:28 taqua Exp $
 *
 * Changes
 * -------
 * 07-Jun-2004 : Added JCommon header (DG);
 *
 */

package org.jfree.base.log;

import org.jfree.util.Log;
import org.jfree.util.LogTarget;
import org.jfree.util.PrintStreamLogTarget;

/**
 * A default log implementation. The Log class defines how to create Logger-contexts
 * and how to forward messages to the logtargets.
 *
 * @author Thomas Morgner
 */
public class DefaultLog extends Log {

    /** The default log target. */
    private static final PrintStreamLogTarget DEFAULT_LOG_TARGET =
          new PrintStreamLogTarget();

    /** The JFreeReport log instance. */
    private static final DefaultLog defaultLogInstance;

    /**
     * Creates a new log.
     */
    public DefaultLog () {
        // nothing required
    }

    static {
        defaultLogInstance = new DefaultLog();
        Log.defineLog(defaultLogInstance);
        defaultLogInstance.addTarget(DEFAULT_LOG_TARGET);
        try {
            // check the system property. This is the developers backdoor to activate
            // debug output as soon as possible.
            if (Boolean.getBoolean("org.jfree.DebugDefault")) {
                defaultLogInstance.setDebuglevel(LogTarget.DEBUG);
            }
            else {
                defaultLogInstance.setDebuglevel(LogTarget.WARN);
            }
        }
        catch (SecurityException se) {
            defaultLogInstance.setDebuglevel(LogTarget.WARN);
        }
    }

    /**
     * Initializes the log system after the log module was loaded and a log target
     * was defined. This is the second step of the log initialisation.
     */
    public void init() {
        removeTarget(DEFAULT_LOG_TARGET);
        final String logLevel = LogConfiguration.getLogLevel();
        if (logLevel.equalsIgnoreCase("error")) {
            setDebuglevel(LogTarget.ERROR);
        }
        else if (logLevel.equalsIgnoreCase("warn")) {
            setDebuglevel(LogTarget.WARN);
        }
        else if (logLevel.equalsIgnoreCase("info")) {
            setDebuglevel(LogTarget.INFO);
        }
        else if (logLevel.equalsIgnoreCase("debug")) {
            setDebuglevel(LogTarget.DEBUG);
        }
    }

    /**
     * Returns the default log.
     * 
     * @return The default log.
     */
    public static DefaultLog getDefaultLog() {
        return defaultLogInstance;
    }
    
}