CentralLoggerFile.java

/*
 ** Module   : CentralLoggerFile.java
 ** Abstract : CentralLogger concrete version for using a custom file.
 **
 ** Copyright (c) 2024, Golden Code Development Corporation.
 **
 ** -#- -I- --Date-- ----------------------------Description-----------------------------
 ** 001 ICP 20240813 Initial version.
 */
/*
 ** This program is free software: you can redistribute it and/or modify
 ** it under the terms of the GNU Affero General Public License as
 ** published by the Free Software Foundation, either version 3 of the
 ** License, or (at your option) any later version.
 **
 ** This program 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 Affero General Public License for more details.
 **
 ** You may find a copy of the GNU Affero GPL version 3 at the following
 ** location: https://www.gnu.org/licenses/agpl-3.0.en.html
 **
 ** Additional terms under GNU Affero GPL version 3 section 7:
 **
 **   Under Section 7 of the GNU Affero GPL version 3, the following additional
 **   terms apply to the works covered under the License.  These additional terms
 **   are non-permissive additional terms allowed under Section 7 of the GNU
 **   Affero GPL version 3 and may not be removed by you.
 **
 **   0. Attribution Requirement.
 **
 **     You must preserve all legal notices or author attributions in the covered
 **     work or Appropriate Legal Notices displayed by works containing the covered
 **     work.  You may not remove from the covered work any author or developer
 **     credit already included within the covered work.
 **
 **   1. No License To Use Trademarks.
 **
 **     This license does not grant any license or rights to use the trademarks
 **     Golden Code, FWD, any Golden Code or FWD logo, or any other trademarks
 **     of Golden Code Development Corporation. You are not authorized to use the
 **     name Golden Code, FWD, or the names of any author or contributor, for
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 **
 **   2. No Misrepresentation of Affiliation.
 **
 **     You may not represent yourself as Golden Code Development Corporation or FWD.
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 **     Golden Code Development Corporation, FWD, or any author or contributor to
 **     the covered work, without written authorization.
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 **     versions of the covered work must be marked in a reasonable way to make it
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 **     Corporation or FWD.  All modified versions must contain the notices of
 **     attribution required in this license.
 */
package com.goldencode.p2j.util.logging;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.logging.*;

/**
 * CentralLogger concrete version for logging into a custom file, supporting multiple configurations.
 */
public class CentralLoggerFile
extends CentralLogger
{
    /** Logger */
    private static final CentralLogger LOG = CentralLogger.get(CentralLoggerFile.class);

    /** The log formatter. */
    private static final Formatter LOG_FORMATTER = new CentralLogFormatter();

    /**  A map that stores instances of CentralLoggerFile keyed by their unique logger names. */
    private static final Map<String, CentralLoggerFile> fileLoggers = new HashMap<>();

    /** A map that stores FileHandler instances keyed by their associated logger names. */
    private static final Map<String, FileHandler> fileHandlers = new HashMap<>();

    /** File handler used by each instance to write log records to a file. */
    private FileHandler customFileHandler;

    /**
     * Private constructor for CentralLoggerFile.
     *
     * @param    loggerName
     *           The name of the logger.
     * @param    level
     *           The level of the logger.
     * @param    checkParentLevels
     *           Flag to prevent recursion for class loaders.
     * @param    excludeSMContext
     *           Flag to prevent deadlock on SecurityManager.
     */
    private CentralLoggerFile(String loggerName,
                              Level level,
                              boolean checkParentLevels,
                              boolean excludeSMContext)
    {
        super(loggerName, level, checkParentLevels, excludeSMContext);
    }

    /**
     * Initializes a file logger for the given configuration.
     *
     * @param    loggerName
     *           Unique name for the logger.
     * @param    filePath
     *           The path of the log file where logs will be written.
     * @param    fileLimit
     *           The maximum size limit for a single log file before it gets rotated.
     * @param    fileCount
     *           The maximum number of log files to maintain in rotation.
     * @return   CentralLoggerFile
     *           The initialized logger instance.
     */
    public static synchronized CentralLoggerFile initialize(String loggerName,
                                                            String filePath,
                                                            int fileLimit,
                                                            int fileCount)
    {
        CentralLoggerFile fileLogger = fileLoggers.get(loggerName);
        if (fileLogger != null)
        {
            return fileLogger;
        }

        fileLogger = new CentralLoggerFile(loggerName, Level.ALL, true, false);

        if (filePath == null || filePath.isEmpty())
        {
            LOG.severe("File path is null or empty. Cannot initialize FileHandler.");
            return fileLogger;
        }

        int resolvedFileLimit = fileLimit == 0 ? 0 : Math.max(fileLimit, MIN_FILE_LIMIT_BYTES);
        int resolvedFileCount = fileCount == 0 ? 0 : Math.max(fileCount, MIN_FILE_COUNT);


        try
        {
            FileHandler fileHandler = (resolvedFileLimit == 0 || resolvedFileCount == 0) ?
                                      new FileHandler(filePath) :
                                      new FileHandler(filePath, resolvedFileLimit, resolvedFileCount);


            fileHandler.setLevel(Level.ALL);
            fileHandler.setFormatter(LOG_FORMATTER);
            fileLogger.customFileHandler = fileHandler;

            fileHandlers.put(loggerName, fileHandler);
            fileLoggers.put(loggerName, fileLogger);
        }
        catch (IOException io)
        {
            LOG.severe("FileHandler couldn't be initialized:", io);
        }

        return fileLogger;
    }

    /**
     * Overloaded method to initialize a file logger with default file limit and file count.
     *
     * @param    loggerName
     *           Unique name for the logger.
     * @param    filePath
     *           The path of the log file where logs will be written.
     * @return   CentralLoggerFile
     *           The initialized logger instance.
     */
    public static synchronized CentralLoggerFile initialize(String loggerName,
                                                            String filePath)
    {
        return initialize(loggerName, filePath, DEFAULT_FILE_LIMIT_BYTES, DEFAULT_FILE_COUNT);
    }

    /**
     * Publishes a log record.
     *
     * @param    logRecord
     *           The log record.
     */
    @Override
    protected void publish(ContextLogRecord logRecord)
    {
        if (customFileHandler != null)
        {
            customFileHandler.publish(logRecord);
            customFileHandler.flush();
        }
        else
        {
            LOG.severe("Attempted to publish log to an uninitialized FileHandler.");
        }
    }

    /**
     * Closes all file handlers associated with this logger.
     */
    public static void closeAllFiles()
    {
        fileHandlers.values().forEach(FileHandler::close);
        fileHandlers.clear();
        fileLoggers.clear();
    }
}