| 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.log4j; |
| 20 | |
| 21 | import java.util.Enumeration; |
| 22 | import java.util.Iterator; |
| 23 | import java.util.Vector; |
| 24 | |
| 25 | import org.apache.log4j.LogManager; |
| 26 | import org.apache.log4j.Logger; |
| 27 | |
| 28 | import org.lttng.ust.agent.LogFrameworkSkeleton; |
| 29 | |
| 30 | public class LTTngLog4j extends LogFrameworkSkeleton { |
| 31 | |
| 32 | private LTTngLogAppender appender; |
| 33 | private Boolean attached; |
| 34 | |
| 35 | public LTTngLog4j(Boolean isRoot) { |
| 36 | super(); |
| 37 | this.appender = new LTTngLogAppender(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 counts 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<?> loggers = LogManager.getCurrentLoggers(); loggers.hasMoreElements(); ) { |
| 73 | Logger logger = (Logger) loggers.nextElement(); |
| 74 | String name = logger.getName(); |
| 75 | logs.add(name); |
| 76 | } |
| 77 | |
| 78 | return logs.iterator(); |
| 79 | } |
| 80 | |
| 81 | @Override |
| 82 | public Boolean isRoot() { |
| 83 | return appender.isRoot(); |
| 84 | } |
| 85 | |
| 86 | @Override |
| 87 | public void reset() { |
| 88 | super.reset(); |
| 89 | detachFromRootLogger(); |
| 90 | } |
| 91 | |
| 92 | private void attachToRootLogger() { |
| 93 | if (this.attached) { |
| 94 | return; |
| 95 | } |
| 96 | |
| 97 | Logger logger = Logger.getRootLogger(); |
| 98 | logger.addAppender(this.appender); |
| 99 | this.attached = true; |
| 100 | } |
| 101 | |
| 102 | private void detachFromRootLogger() { |
| 103 | if (!this.attached) { |
| 104 | return; |
| 105 | } |
| 106 | |
| 107 | Logger logger = Logger.getRootLogger(); |
| 108 | logger.removeAppender(this.appender); |
| 109 | this.attached = false; |
| 110 | } |
| 111 | } |