liblttng-ust-java-agent/java/org/lttng/ust/agent/jul/LTTngJUL.java

   1 /*
   2  * Copyright (C) 2014 - Christian Babeux <christian.babeux@efficios.com>
   3  *
   4  *
   5  * This library is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU Lesser General Public License, version 2.1 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This library is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
  12  * for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public License
  15  * along with this library; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 package org.lttng.ust.agent.jul;
  20
  21 import java.util.Enumeration;
  22 import java.util.Iterator;
  23 import java.util.Vector;
  24
  25 import java.util.logging.LogManager;
  26 import java.util.logging.Logger;
  27
  28 import org.lttng.ust.agent.LogFrameworkSkeleton;
  29
  30 public class LTTngJUL extends LogFrameworkSkeleton {
  31
  32         private LTTngLogHandler handler;
  33         private Boolean attached;
  34
  35         public LTTngJUL(Boolean isRoot) {
  36                 super();
  37                 this.handler = new LTTngLogHandler(isRoot);
  38                 this.attached = false;
  39         }
  40
  41         @Override
  42         public Boolean enableLogger(String name) {
  43                 if(!super.enableLogger(name)) {
  44                         return false;
  45                 }
  46
  47                 /* The first enable of any event triggers the attachment to the root logger */
  48                 if (getEventCount() == 1 && !this.attached) {
  49                         attachToRootLogger();
  50                 }
  51
  52                 return true;
  53         }
  54
  55         @Override
  56         public Boolean disableLogger(String name) {
  57                 if(!super.disableLogger(name)) {
  58                         return false;
  59                 }
  60
  61                 /* Detach from the root logger when the event count reach zero */
  62                 if (getEventCount() == 0 && this.attached) {
  63                         detachFromRootLogger();
  64                 }
  65
  66                 return true;
  67         }
  68
  69         @Override
  70         public Iterator<String> listLoggers() {
  71                 Vector<String> logs = new Vector<String>();
  72                 for (Enumeration<String> loggers = LogManager.getLogManager().getLoggerNames(); loggers.hasMoreElements(); ) {
  73                         String name = loggers.nextElement();
  74                         /* Skip the root logger */
  75                         if (name.equals("")) {
  76                                 continue;
  77                         }
  78
  79                         logs.add(name);
  80                 }
  81
  82                 return logs.iterator();
  83         }
  84
  85         @Override
  86         public Boolean isRoot() {
  87                 return handler.isRoot();
  88         }
  89
  90         @Override
  91         public void reset() {
  92                 super.reset();
  93                 detachFromRootLogger();
  94         }
  95
  96         private void attachToRootLogger() {
  97                 if (this.attached) {
  98                         return;
  99                 }
 100
 101                 Logger rootLogger = LogManager.getLogManager().getLogger("");
 102                 rootLogger.addHandler(this.handler);
 103                 this.attached = true;
 104         }
 105
 106         private void detachFromRootLogger() {
 107                 if (!this.attached) {
 108                         return;
 109                 }
 110
 111                 Logger rootLogger = LogManager.getLogManager().getLogger("");
 112                 rootLogger.removeHandler(this.handler);
 113                 this.attached = false;
 114         }
 115 }