fr.opensagres.xdocreport.core.logging.LogUtils.java Source code

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Here is the source code for fr.opensagres.xdocreport.core.logging.LogUtils.java

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/**
 * Copyright (C) 2011 Angelo Zerr <angelo.zerr@gmail.com> and Pascal Leclercq <pascal.leclercq@gmail.com>
 *
 * All rights reserved.
 *
 * Permission is hereby granted, free  of charge, to any person obtaining
 * a  copy  of this  software  and  associated  documentation files  (the
 * "Software"), to  deal in  the Software without  restriction, including
 * without limitation  the rights to  use, copy, modify,  merge, publish,
 * distribute,  sublicense, and/or sell  copies of  the Software,  and to
 * permit persons to whom the Software  is furnished to do so, subject to
 * the following conditions:
 *
 * The  above  copyright  notice  and  this permission  notice  shall  be
 * included in all copies or substantial portions of the Software.
 *
 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
 * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
 * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

package fr.opensagres.xdocreport.core.logging;

import static fr.opensagres.xdocreport.core.utils.StringUtils.isEmpty;

import java.lang.reflect.Constructor;
import java.text.MessageFormat;
import java.util.logging.Level;
import java.util.logging.LogRecord;
import java.util.logging.Logger;

/**
 * A container for static utility methods related to logging.
 * <p>
 * Inspired from org.apache.cxf.common.logging.LogUtils
 * </p>
 * 
 * @author pascalleclercq
 */
@SuppressWarnings("unchecked")
public final class LogUtils {

    private static final Object[] NO_PARAMETERS = new Object[0];

    private static Class<? extends AbstractDelegatingLogger> loggerClass;

    // for testing purpose
    static void setLoggerClass(Class<? extends AbstractDelegatingLogger> loggerClass) {
        LogUtils.loggerClass = loggerClass;
    }

    static Class<? extends AbstractDelegatingLogger> getLoggerClass() {
        return loggerClass;
    }

    /**
     * Prevents instantiation.
     */
    private LogUtils() {
    }

    static {

        try {
            String cname = null;

            Class.forName("org.slf4j.impl.StaticLoggerBinder");
            Class<?> cls = Class.forName("org.slf4j.LoggerFactory");
            Class<?> fcls = cls.getMethod("getILoggerFactory").invoke(null).getClass();
            if (fcls.getName().contains("Log4j")) {
                cname = "fr.opensagres.xdocreport.core.logging.Log4jLogger";
            } else if (fcls.getName().contains("JCL")) {
                cls = Class.forName("org.apache.commons.logging.LogFactory");
                fcls = cls.getMethod("getFactory").invoke(null).getClass();
                if (fcls.getName().contains("Log4j")) {
                    cname = "fr.opensagres.xdocreport.core.logging.Log4jLogger";
                }
            } else {
                cname = "fr.opensagres.xdocreport.core.logging.Slf4jLogger";
            }

            if (!isEmpty(cname)) {
                try {

                    loggerClass = (Class<? extends AbstractDelegatingLogger>) Class.forName(cname.trim(), true,
                            Thread.currentThread().getContextClassLoader());
                } catch (Throwable ex) {
                    loggerClass = (Class<? extends AbstractDelegatingLogger>) Class.forName(cname.trim());
                }
                getLogger(LogUtils.class).fine("Using " + loggerClass.getName() + " for logging.");
            }
        } catch (Throwable ex) {
            // ignore - if we get here, some issue prevented the logger class
            // from being loaded.
            // maybe a ClassNotFound or NoClassDefFound or similar. Just use
            // j.u.l
            loggerClass = null;
        }
    }

    /**
     * Get a Logger with the associated default resource bundle for the class.
     * 
     * @param cls the Class to contain the Logger
     * @return an appropriate Logger
     */
    public static Logger getLogger(Class<?> cls) {
        return createLogger(cls.getName());
    }

    /**
     * Create a logger
     */
    protected static Logger createLogger(String loggerName) {
        if (loggerClass != null) {

            try {

                Constructor<? extends AbstractDelegatingLogger> cns = loggerClass.getConstructor(String.class);
                return cns.newInstance(loggerName);

            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
        return Logger.getLogger(loggerName, null);

    }

    /**
     * Allows both parameter substitution and a typed Throwable to be logged.
     * 
     * @param logger the Logger the log to
     * @param level the severity level
     * @param message the log message
     * @param throwable the Throwable to log
     * @param parameter the parameter to substitute into message
     */
    public static void log(Logger logger, Level level, String message, Throwable throwable, Object parameter) {
        if (logger.isLoggable(level)) {
            final String formattedMessage = MessageFormat.format(message, parameter);
            doLog(logger, level, formattedMessage, throwable);
        }
    }

    /**
     * Allows both parameter substitution and a typed Throwable to be logged.
     * 
     * @param logger the Logger the log to
     * @param level the severity level
     * @param message the log message
     * @param throwable the Throwable to log
     * @param parameters the parameters to substitute into message
     */
    public static void log(Logger logger, Level level, String message, Throwable throwable, Object... parameters) {
        if (logger.isLoggable(level)) {
            final String formattedMessage = MessageFormat.format(message, parameters);
            doLog(logger, level, formattedMessage, throwable);
        }
    }

    /**
     * Checks log level and logs
     * 
     * @param logger the Logger the log to
     * @param level the severity level
     * @param message the log message
     */
    public static void log(Logger logger, Level level, String message) {
        log(logger, level, message, NO_PARAMETERS);
    }

    /**
     * Checks log level and logs
     * 
     * @param logger the Logger the log to
     * @param level the severity level
     * @param message the log message
     * @param throwable the Throwable to log
     */
    public static void log(Logger logger, Level level, String message, Throwable throwable) {
        log(logger, level, message, throwable, NO_PARAMETERS);
    }

    /**
     * Checks log level and logs
     * 
     * @param logger the Logger the log to
     * @param level the severity level
     * @param message the log message
     * @param parameter the parameter to substitute into message
     */
    public static void log(Logger logger, Level level, String message, Object parameter) {
        log(logger, level, message, new Object[] { parameter });
    }

    /**
     * Checks log level and logs
     * 
     * @param logger the Logger the log to
     * @param level the severity level
     * @param message the log message
     * @param parameters the parameters to substitute into message
     */
    public static void log(Logger logger, Level level, String message, Object[] parameters) {
        if (logger.isLoggable(level)) {

            doLog(logger, level, message, null);
        }
    }

    private static void doLog(Logger log, Level level, String msg, Throwable t) {
        LogRecord record = new LogRecord(level, msg);

        record.setLoggerName(log.getName());
        record.setResourceBundleName(log.getResourceBundleName());
        record.setResourceBundle(log.getResourceBundle());

        if (t != null) {
            record.setThrown(t);
        }

        // try to get the right class name/method name - just trace
        // back the stack till we get out of this class
        StackTraceElement stack[] = (new Throwable()).getStackTrace();
        String cname = LogUtils.class.getName();
        for (int x = 0; x < stack.length; x++) {
            StackTraceElement frame = stack[x];
            if (!frame.getClassName().equals(cname)) {
                record.setSourceClassName(frame.getClassName());
                record.setSourceMethodName(frame.getMethodName());
                break;
            }
        }
        log.log(record);
    }

    public static Logger getLogger(String name) {
        return createLogger(name);
    }

}