001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache license, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the license for the specific language governing permissions and
015 * limitations under the license.
016 */
017 package org.apache.logging.log4j.core.appender.rolling;
018
019 import java.lang.reflect.Method;
020
021 import org.apache.logging.log4j.core.LogEvent;
022 import org.apache.logging.log4j.core.config.plugins.Plugin;
023 import org.apache.logging.log4j.core.config.plugins.PluginFactory;
024 import org.apache.logging.log4j.core.util.Loader;
025 import org.apache.logging.log4j.status.StatusLogger;
026
027 /**
028 * Triggers a rollover on every restart. The target file's timestamp is compared with the JVM start time
029 * and if it is older isTriggeringEvent will return true. After isTriggeringEvent has been called it will
030 * always return false.
031 */
032 @Plugin(name = "OnStartupTriggeringPolicy", category = "Core", printObject = true)
033 public class OnStartupTriggeringPolicy implements TriggeringPolicy {
034 private static long JVM_START_TIME = initStartTime();
035
036 private boolean evaluated = false;
037 private RollingFileManager manager;
038
039 /**
040 * Provide the RollingFileManager to the policy.
041 * @param manager The RollingFileManager.
042 */
043 @Override
044 public void initialize(final RollingFileManager manager) {
045 this.manager = manager;
046 if (JVM_START_TIME == 0) {
047 evaluated = true;
048 }
049 }
050
051 /**
052 * Returns the result of {@code ManagementFactory.getRuntimeMXBean().getStartTime()},
053 * or the current system time if JMX is not available.
054 */
055 private static long initStartTime() {
056 // LOG4J2-379:
057 // We'd like to call ManagementFactory.getRuntimeMXBean().getStartTime(),
058 // but Google App Engine throws a java.lang.NoClassDefFoundError
059 // "java.lang.management.ManagementFactory is a restricted class".
060 // The reflection is necessary because without it, Google App Engine
061 // will refuse to initialize this class.
062 try {
063 final Class<?> factoryClass = Loader.loadSystemClass("java.lang.management.ManagementFactory");
064 final Method getRuntimeMXBean = factoryClass.getMethod("getRuntimeMXBean");
065 final Object runtimeMXBean = getRuntimeMXBean.invoke(null);
066
067 final Class<?> runtimeMXBeanClass = Loader.loadSystemClass("java.lang.management.RuntimeMXBean");
068 final Method getStartTime = runtimeMXBeanClass.getMethod("getStartTime");
069 final Long result = (Long) getStartTime.invoke(runtimeMXBean);
070
071 return result.longValue();
072 } catch (final Throwable t) {
073 StatusLogger.getLogger().error("Unable to call ManagementFactory.getRuntimeMXBean().getStartTime(), " //
074 + "using system time for OnStartupTriggeringPolicy", t);
075 // We have little option but to declare "now" as the beginning of time.
076 return System.currentTimeMillis();
077 }
078 }
079
080 /**
081 * Determine if a rollover should be triggered.
082 * @param event A reference to the current event.
083 * @return true if the target file's timestamp is older than the JVM start time.
084 */
085 @Override
086 public boolean isTriggeringEvent(final LogEvent event) {
087 if (evaluated) {
088 return false;
089 }
090 evaluated = true;
091 return manager.getFileTime() < JVM_START_TIME;
092 }
093
094 @Override
095 public String toString() {
096 return "OnStartupTriggeringPolicy";
097 }
098
099 @PluginFactory
100 public static OnStartupTriggeringPolicy createPolicy() {
101 return new OnStartupTriggeringPolicy();
102 }
103 }