Glassfish example source code file (FileLogger.java)

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Java - Glassfish tags/keywords

file, file, filelogger, filewriter, io, ioexception, jdbc, lifecycleexception, lifecycleexception, loggerbase, printwriter, printwriter, sql, string, string, stringmanager, timestamp

The Glassfish FileLogger.java source code

/*
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 *
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 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
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 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
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 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 *
 *
 * This file incorporates work covered by the following copyright and
 * permission notice:
 *
 * Copyright 2004 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.catalina.logger;


import org.apache.catalina.LifecycleException;
import org.apache.catalina.util.StringManager;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Timestamp;


/**
 * Implementation of <b>Logger that appends log messages to a file
 * named {prefix}.{date}.{suffix} in a configured directory, with an
 * optional preceding timestamp.
 *
 * @author Craig R. McClanahan
 * @version $Revision: 1.3 $ $Date: 2006/10/03 20:19:12 $
 */

public class FileLogger
    extends LoggerBase {


    // ----------------------------------------------------- Instance Variables


    /**
     * The as-of date for the currently open log file, or a zero-length
     * string if there is no open log file.
     */
    private String date = "";


    /**
     * The directory in which log files are created.
     */
    private String directory = "logs";


    /**
     * The descriptive information about this implementation.
     */
    protected static final String info =
        "org.apache.catalina.logger.FileLogger/1.0";


    /**
     * The prefix that is added to log file filenames.
     */
    private String prefix = "catalina.";


    /**
     * The string manager for this package.
     */
    private static final StringManager sm =
        StringManager.getManager(Constants.Package);


    /**
     * Has this component been started?
     */
    private boolean started = false;


    /**
     * The suffix that is added to log file filenames.
     */
    private String suffix = ".log";


    /**
     * Should logged messages be date/time stamped?
     */
    private boolean timestamp = false;


    /**
     * The PrintWriter to which we are currently logging, if any.
     */
    private PrintWriter writer = null;


    // ------------------------------------------------------------- Properties


    /**
     * Return the directory in which we create log files.
     */
    public String getDirectory() {

        return (directory);

    }


    /**
     * Set the directory in which we create log files.
     *
     * @param directory The new log file directory
     */
    public void setDirectory(String directory) {

        String oldDirectory = this.directory;
        this.directory = directory;
        support.firePropertyChange("directory", oldDirectory, this.directory);

    }


    /**
     * Return the log file prefix.
     */
    public String getPrefix() {

        return (prefix);

    }


    /**
     * Set the log file prefix.
     *
     * @param prefix The new log file prefix
     */
    public void setPrefix(String prefix) {

        String oldPrefix = this.prefix;
        this.prefix = prefix;
        support.firePropertyChange("prefix", oldPrefix, this.prefix);

    }


    /**
     * Return the log file suffix.
     */
    public String getSuffix() {

        return (suffix);

    }


    /**
     * Set the log file suffix.
     *
     * @param suffix The new log file suffix
     */
    public void setSuffix(String suffix) {

        String oldSuffix = this.suffix;
        this.suffix = suffix;
        support.firePropertyChange("suffix", oldSuffix, this.suffix);

    }


    /**
     * Return the timestamp flag.
     */
    public boolean getTimestamp() {

        return (timestamp);

    }


    /**
     * Set the timestamp flag.
     *
     * @param timestamp The new timestamp flag
     */
    public void setTimestamp(boolean timestamp) {

        boolean oldTimestamp = this.timestamp;
        this.timestamp = timestamp;
        support.firePropertyChange("timestamp", Boolean.valueOf(oldTimestamp),
                                   Boolean.valueOf(this.timestamp));

    }


    // --------------------------------------------------------- Public Methods


    /**
     * Writes the specified message to a servlet log file, usually an event
     * log.  The name and type of the servlet log is specific to the
     * servlet container.
     *
     * @param msg A <code>String specifying the message to be written
     *  to the log file
     */
    public void log(String msg) {

        // Construct the timestamp we will use, if requested
        Timestamp ts = new Timestamp(System.currentTimeMillis());
        String tsString = ts.toString().substring(0, 19);
        String tsDate = tsString.substring(0, 10);

        // If the date has changed, switch log files
        if (!date.equals(tsDate)) {
            synchronized (this) {
                if (!date.equals(tsDate)) {
                    close();
                    date = tsDate;
                    open();
                }
            }
        }

        // Log this message, timestamped if necessary
        if (writer != null) {
            if (timestamp) {
                writer.println(tsString + " " + msg);
            } else {
                writer.println(msg);
            }
        }

    }


    // -------------------------------------------------------- Private Methods


    /**
     * Close the currently open log file (if any)
     */
    private void close() {

        if (writer == null)
            return;
        writer.flush();
        writer.close();
        writer = null;
        date = "";

    }


    /**
     * Open the new log file for the date specified by <code>date.
     */
    private void open() {

        // Create the directory if necessary
        File dir = new File(directory);
        if (!dir.isAbsolute())
            dir = new File(System.getProperty("catalina.base"), directory);
        dir.mkdirs();

        // Open the current log file
        try {
            String pathname = dir.getAbsolutePath() + File.separator +
                prefix + date + suffix;
            writer = new PrintWriter(new FileWriter(pathname, true), true);
        } catch (IOException e) {
            writer = null;
        }

    }


    // ------------------------------------------------------ Lifecycle Methods


    /**
     * Prepare for the beginning of active use of the public methods of this
     * component.  This method should be called after <code>configure(),
     * and before any of the public methods of the component are utilized.
     *
     * @exception LifecycleException if this component detects a fatal error
     *  that prevents this component from being used
     */
    public void start() throws LifecycleException {

        // Validate and update our current component state
        if (started)
            throw new LifecycleException
                (sm.getString("fileLogger.alreadyStarted"));
        lifecycle.fireLifecycleEvent(START_EVENT, null);
        started = true;
        
        super.start();

    }


    /**
     * Gracefully terminate the active use of the public methods of this
     * component.  This method should be the last one called on a given
     * instance of this component.
     *
     * @exception LifecycleException if this component detects a fatal error
     *  that needs to be reported
     */
    public void stop() throws LifecycleException {

        // Validate and update our current component state
        if (!started)
            throw new LifecycleException
                (sm.getString("fileLogger.notStarted"));
        lifecycle.fireLifecycleEvent(STOP_EVENT, null);
        started = false;

        close();
        
        super.stop();

    }


}