org.ops4j.pax.logging.internal.Activator Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of pax-logging-api Show documentation
The Pax Logging API Library is to allow for the Pax Logging Service to be reloaded without stopping the many dependent bundles. It also contains the OSGi Log Service API and the Knopflerfish Log API.
There is a newer version: 2.2.8
Show newest version
/*  Copyright 2007 Niclas Hedhman.
 *
 * 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.ops4j.pax.logging.internal;

import java.util.LinkedList;
import java.util.List;
import java.util.logging.Handler;
import java.util.logging.LogManager;

import org.apache.log4j.helpers.LogLog;
import org.apache.logging.log4j.util.PaxPropertySource;
import org.ops4j.pax.logging.OSGIPaxLoggingManager;
import org.ops4j.pax.logging.PaxLoggingConstants;
import org.ops4j.pax.logging.PaxLoggingManager;
import org.ops4j.pax.logging.PaxLoggingManagerAwareLogger;
import org.ops4j.pax.logging.spi.support.BackendSupport;
import org.ops4j.pax.logging.spi.support.DefaultServiceLog;
import org.ops4j.pax.logging.spi.support.FallbackLogFactory;
import org.ops4j.pax.logging.spi.support.FrameworkHandler;
import org.ops4j.pax.logging.spi.support.OsgiUtil;
import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;

public class Activator implements BundleActivator {

    /**
     * This list will keep facade-specific loggers before {@link PaxLoggingManager} becomes available.
     * Access to this list should be synchronized.
     */
    public static final List m_loggers = new LinkedList<>();

    private PaxLoggingManager manager;

    // optional JUL handler to bridge events to pax-logging
    private JdkHandler m_JdkHandler;

    // bundle/service/framework listener that logs events into log service
    // as required by "101.6 Mapping of Events"
    private FrameworkHandler m_frameworkHandler;
    private BundleContext bundleContext;

    public void start(BundleContext bundleContext) throws Exception {
        this.bundleContext = bundleContext;
        String name = getClass().getName();

        // This class is effectively a tracker of PaxLoggingService services - there should be only one
        // before this instance is created and before it's passed to setPaxLoggingManager() static method of
        // logger factories, other bundles may already call logging factories to obtain loggers.
        // all such obtained loggers (before pax-logging-api starts) have internal m_delegate set to default logger
        // There's no caching at individual logger factory level.
        // when pax-logging-api finally starts, all such loggers need to replace their m_delegate to real TrackingLogger
        // obtained from this OSGIPaxLoggingManager.
        manager = new OSGIPaxLoggingManager(bundleContext);

        // Fallback PaxLogger configuration
        String levelName = BackendSupport.defaultLogLevel(bundleContext);
        DefaultServiceLog.setLogLevel(levelName);

        // Log4j1 debug
        LogLog.setInternalDebugging(DefaultServiceLog.getStaticLogLevel() <= DefaultServiceLog.DEBUG);
        // Log4j2 debug
        PaxPropertySource.debug = DefaultServiceLog.getStaticLogLevel() <= DefaultServiceLog.DEBUG;
        PaxPropertySource.defaultLevel = levelName;

        // for JUL we may install bridging java.util.logging.Handler just like org.slf4j:jul-to-slf4j
        if (!skipJulRegistration()) {
            LogManager logManager = LogManager.getLogManager();

            if (!skipJulReset()) {
                logManager.reset();
            }

            // clear out old handlers
            java.util.logging.Logger rootLogger = logManager.getLogger("");
            Handler[] handlers = rootLogger.getHandlers();
            for (int i = 0; i < handlers.length; i++) {
                rootLogger.removeHandler(handlers[i]);
            }
            rootLogger.setFilter(null);

            m_JdkHandler = new JdkHandler(manager);
            m_JdkHandler.setBundleContext(bundleContext);
            rootLogger.addHandler(m_JdkHandler);
            rootLogger.setLevel(BackendSupport.toJULLevel(levelName));

            java.util.logging.Logger julLogger = java.util.logging.Logger.getLogger(name);
            julLogger.info("Enabling Java Util Logging API support.");
        }

        // for each logging framework/facade supported, we'll:
        // 1. configure the facade/bridge/factory with single instance of PaxLoggingManager
        // 2. obtain the framework specific log(ger)
        // 3. use the log(ger)

        // SLF4J
        org.ops4j.pax.logging.slf4j.Slf4jLoggerFactory.setPaxLoggingManager(manager);
        org.slf4j.Logger slf4jLogger = org.slf4j.LoggerFactory.getLogger(name);
        slf4jLogger.info("Enabling SLF4J API support.");

        // Apache Commons Logging
        org.apache.commons.logging.LogFactory.setPaxLoggingManager(manager);
        org.apache.commons.logging.Log commonsLogger = org.apache.commons.logging.LogFactory.getLog(name);
        commonsLogger.info("Enabling Apache Commons Logging API support.");

        // Apache Juli Logging
        org.apache.juli.logging.LogFactory.setPaxLoggingManager(manager);
        org.apache.juli.logging.Log juliLogger = org.apache.juli.logging.LogFactory.getLog(name);
        juliLogger.info("Enabling JULI Logger API support.");

        // Avalon Logging
        org.ops4j.pax.logging.avalon.AvalonLogFactory.setPaxLoggingManager(manager);
        org.apache.avalon.framework.logger.Logger avalonLogger = org.ops4j.pax.logging.avalon.AvalonLogFactory.getLogger(name);
        avalonLogger.info("Enabling Avalon Logger API support.");

        // JBoss Logging
        org.ops4j.pax.logging.jbosslogging.PaxLoggingLoggerProvider.setPaxLoggingManager(manager);
        org.jboss.logging.Logger jbossLoggingLogger = org.jboss.logging.Logger.getLogger(name);
        jbossLoggingLogger.info("Enabling JBoss Logging API support.");

        // Log4j1 API
        org.apache.log4j.Logger.configurePaxLoggingManager(manager);
        org.apache.log4j.Logger log4j1Logger = org.apache.log4j.Logger.getLogger(name);
        log4j1Logger.info("Enabling Log4J v1 API support.");

        // Log4j2
        org.ops4j.pax.logging.log4jv2.Log4jv2LoggerContext.setPaxLoggingManager(manager);
        org.apache.logging.log4j.Logger log4j2Logger = org.apache.logging.log4j.LogManager.getLogger(name);
        log4j2Logger.info("Enabling Log4J v2 API support.");

        // after all the above facades are configured to get loggers from PaxLoggingManager (and further - from
        // specific PaxLoggingService), we just have to reconfigure already created loggers - the ones
        // that use m_delegate obtained from FallbackLogFactory
        synchronized (m_loggers) {
            // We need to instruct all loggers to ensure they delegate to proper PaxLogger that delegates to
            // actual PaxLoggingService
            for (PaxLoggingManagerAwareLogger logger : m_loggers) {
                logger.setPaxLoggingManager(manager);
            }
            // these loggers can be cleared now because they'll be using TrackingLogger forever
            // and these are cached at OSGiPaxLoggingManager from now on
            m_loggers.clear();
        }

        // handler that logs framework/bundle/service events, according to OSGi Compendium R6 101.6
        m_frameworkHandler = new FrameworkHandler(bundleContext, manager);
        bundleContext.addBundleListener(m_frameworkHandler);
        bundleContext.addFrameworkListener(m_frameworkHandler);
        bundleContext.addServiceListener(m_frameworkHandler);
    }

    public void stop(BundleContext bundleContext) throws Exception {
        // Clean up the listeners.
        if (m_frameworkHandler != null) {
            bundleContext.removeBundleListener(m_frameworkHandler);
            bundleContext.removeFrameworkListener(m_frameworkHandler);
            bundleContext.removeServiceListener(m_frameworkHandler);
        }

        String name = getClass().getName();

        org.slf4j.Logger slf4jLogger = org.slf4j.LoggerFactory.getLogger(name);
        slf4jLogger.info("Disabling SLF4J API support.");
        org.ops4j.pax.logging.slf4j.Slf4jLoggerFactory.setPaxLoggingManager(null);

        org.apache.commons.logging.Log commonsLogger = org.apache.commons.logging.LogFactory.getLog(name);
        commonsLogger.info("Disabling Apache Commons Logging API support.");
        org.apache.commons.logging.LogFactory.setPaxLoggingManager(null);

        org.apache.juli.logging.Log juliLogger = org.apache.juli.logging.LogFactory.getLog(name);
        juliLogger.info("Disabling JULI Logger API support.");
        org.apache.juli.logging.LogFactory.setPaxLoggingManager(null);

        org.apache.avalon.framework.logger.Logger avalonLogger = org.ops4j.pax.logging.avalon.AvalonLogFactory.getLogger(name);
        avalonLogger.info("Disabling Avalon Logger API support.");
        org.ops4j.pax.logging.avalon.AvalonLogFactory.setPaxLoggingManager(null);

        org.jboss.logging.Logger jbossLoggingLogger = org.jboss.logging.Logger.getLogger(name);
        jbossLoggingLogger.info("Disabling JBoss Logging API support.");
        org.ops4j.pax.logging.jbosslogging.PaxLoggingLoggerProvider.setPaxLoggingManager(null);

        org.apache.log4j.Logger log4j1Logger = org.apache.log4j.Logger.getLogger(name);
        log4j1Logger.info("Disabling Log4J v1 API support.");
        org.apache.log4j.Logger.configurePaxLoggingManager(null);

        org.apache.logging.log4j.Logger log4j2Logger = org.apache.logging.log4j.LogManager.getLogger(getClass());
        log4j2Logger.info("Disabling Log4J v2 API support.");
        org.ops4j.pax.logging.log4jv2.Log4jv2LoggerContext.setPaxLoggingManager(null);

        synchronized (m_loggers) {
            // We need to instruct all loggers that they should again switch to fallback loggers
            // this list should however be empty, because it was cleared after proper OSGiPaxLoggingManager
            // was set in all logger factories. But lets leave this loop here.
            for (PaxLoggingManagerAwareLogger logger : m_loggers) {
                logger.setPaxLoggingManager(null);
            }
        }

        // Remove the global handler for all JDK Logging (java.util.logging).
        if (m_JdkHandler != null) {
            java.util.logging.Logger julLogger = java.util.logging.Logger.getLogger(name);
            julLogger.info("Disabling Java Util Logging API support.");

            java.util.logging.Logger rootLogger = LogManager.getLogManager().getLogger("");
            rootLogger.removeHandler(m_JdkHandler);
            m_JdkHandler.flush();
            m_JdkHandler.close();
            m_JdkHandler = null;
        }

        if (manager != null) {
            manager.dispose();
            manager.close();
        }

        FallbackLogFactory.cleanup();
    }

    private boolean skipJulRegistration() {
        String property = OsgiUtil.systemOrContextProperty(bundleContext, PaxLoggingConstants.LOGGING_CFG_SKIP_JUL);
        return Boolean.parseBoolean(property);
    }

    private boolean skipJulReset() {
        String property = OsgiUtil.systemOrContextProperty(bundleContext, PaxLoggingConstants.LOGGING_CFG_SKIP_JUL_RESET);
        return Boolean.parseBoolean(property);
    }

}