opendaylight/adsal/logging/bridge/src/main/java/org/opendaylight/controller/logging/bridge/internal/Activator.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.logging.bridge.internal;
   9
  10 import org.osgi.service.log.LogEntry;
  11
  12 import java.lang.Thread.UncaughtExceptionHandler;
  13 import java.util.Enumeration;
  14
  15 import org.osgi.framework.BundleContext;
  16 import org.osgi.framework.BundleException;
  17 import org.osgi.framework.BundleActivator;
  18 import org.osgi.framework.ServiceReference;
  19 import org.slf4j.Logger;
  20 import org.slf4j.LoggerFactory;
  21 import org.slf4j.ILoggerFactory;
  22 import org.osgi.service.log.LogReaderService;
  23
  24 public class Activator implements BundleActivator {
  25     private static final String UNCAUGHT_EXCEPTION_POLICY_PROP = "controller.uncaughtExceptionPolicy";
  26     private static final UncaughtExceptionPolicy DEFAULT_UNCAUGHT_EXCEPTION_POLICY = UncaughtExceptionPolicy.IGNORE;
  27
  28     private LogListenerImpl listener = null;
  29     private ShutdownHandler shutdownHandler = null;
  30     private Logger log = null;
  31
  32     @Override
  33     public void start(BundleContext context) {
  34         // Lets trigger the resolution of the slf4j logger factory
  35         ILoggerFactory f = LoggerFactory.getILoggerFactory();
  36
  37         // Now retrieve a logger for the bridge
  38         log = f
  39                 .getLogger("org.opendaylight.controller.logging.bridge.OSGI2SLF4J");
  40
  41         if (this.log != null) {
  42             this.listener = new LogListenerImpl(log);
  43
  44             ServiceReference service = null;
  45             service = context.getServiceReference(LogReaderService.class
  46                     .getName());
  47             if (service != null) {
  48                 LogReaderService reader = (LogReaderService) context
  49                         .getService(service);
  50                 if (reader == null) {
  51                     this.log.error("Cannot register the LogListener because "
  52                             + "cannot retrieve LogReaderService");
  53                 } else {
  54                     reader.addLogListener(this.listener);
  55                     // Now lets walk all the exiting messages
  56                     Enumeration<LogEntry> entries = reader.getLog();
  57                     if (entries != null) {
  58                         while (entries.hasMoreElements()) {
  59                             LogEntry entry = entries.nextElement();
  60                             this.listener.logged(entry);
  61                         }
  62                     }
  63                 }
  64
  65                 /*
  66                  * Install the default exception handler so that the uncaught
  67                  * exceptions are handled by our customized handler. This new
  68                  * handler will display the exceptions to OSGI console as well
  69                  * as log to file.
  70                  */
  71                 UncaughtExceptionHandler handler = DEFAULT_UNCAUGHT_EXCEPTION_POLICY;
  72                 final String policy = context.getProperty(UNCAUGHT_EXCEPTION_POLICY_PROP);
  73                 if (policy != null) {
  74                     try {
  75                         handler = UncaughtExceptionPolicy.valueOf(policy.toUpperCase());
  76                     } catch (IllegalArgumentException ex) {
  77                         log.warn("Invalid policy name \"{}\", defaulting to {}", policy, handler);
  78                     }
  79                 }
  80                 log.trace("Setting uncaught exception policy to {}", handler);
  81                 Thread.setDefaultUncaughtExceptionHandler(handler);
  82
  83                 /*
  84                  * Install the Shutdown handler. This will intercept SIGTERM signal and
  85                  * close the system bundle. This allows for a graceful  closing of OSGI
  86                  * framework.
  87                  */
  88                 shutdownHandler = new ShutdownHandler(context);
  89                 Runtime.getRuntime().addShutdownHook(shutdownHandler);
  90             } else {
  91                 this.log.error("Cannot register the LogListener because "
  92                         + "cannot retrieve LogReaderService");
  93             }
  94         } else {
  95             System.err
  96                     .println("Could not initialize the logging bridge subsytem");
  97         }
  98     }
  99
 100     @Override
 101     public void stop(BundleContext context) {
 102         ServiceReference serviceRef = context.getServiceReference(
 103                 LogReaderService.class.getName());
 104         if (serviceRef != null) {
 105             LogReaderService reader = (LogReaderService) context.getService(serviceRef);
 106             reader.removeLogListener(this.listener);
 107         }
 108         if (this.shutdownHandler != null) {
 109             Runtime.getRuntime().removeShutdownHook(this.shutdownHandler);
 110         }
 111         this.listener = null;
 112         this.log = null;
 113         this.shutdownHandler = null;
 114     }
 115
 116     private class ShutdownHandler extends Thread {
 117         BundleContext bundlecontext;
 118         public ShutdownHandler(BundleContext ctxt) {
 119                 this.bundlecontext = ctxt;
 120         }
 121
 122         @Override
 123         public void run () {
 124             try {
 125                 this.bundlecontext.getBundle(0).stop();
 126                 log.debug("shutdown handler thread called");
 127             } catch (BundleException e) {
 128                 log.debug("Bundle couldn't be stopped");
 129             } catch (Exception e) {
 130                 log.debug("Unhandled exception");
 131             }
 132         }
 133     }
 134
 135 }