| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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.apache.logging.log4j.core.time; |
| |
| import org.apache.logging.log4j.core.time.internal.CachedClock; |
| import org.apache.logging.log4j.core.time.internal.CoarseCachedClock; |
| import org.apache.logging.log4j.core.time.internal.SystemClock; |
| import org.apache.logging.log4j.core.time.internal.SystemMillisClock; |
| import org.apache.logging.log4j.core.util.Loader; |
| import org.apache.logging.log4j.status.StatusLogger; |
| import org.apache.logging.log4j.util.PropertiesUtil; |
| import org.apache.logging.log4j.util.Supplier; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| /** |
| * Factory for {@code Clock} objects. |
| * |
| * @since 2.11 |
| */ |
| public final class ClockFactory { |
| |
| /** |
| * Name of the system property that can be used to specify a {@code Clock} |
| * implementation class. The value of this property is {@value}. |
| */ |
| public static final String PROPERTY_NAME = "log4j.Clock"; |
| private static final StatusLogger LOGGER = StatusLogger.getLogger(); |
| |
| // private static final Clock clock = createClock(); |
| |
| private ClockFactory() { |
| } |
| |
| /** |
| * Returns a {@code Clock} instance depending on the value of system |
| * property {@link #PROPERTY_NAME}. |
| * <p> |
| * If system property {@code log4j.Clock=CachedClock} is specified, |
| * this method returns an instance of {@link CachedClock}. If system |
| * property {@code log4j.Clock=CoarseCachedClock} is specified, this |
| * method returns an instance of {@link CoarseCachedClock}. |
| * </p> |
| * <p> |
| * If another value is specified, this value is taken as the fully qualified |
| * class name of a class that implements the {@code Clock} interface. An |
| * object of this class is instantiated and returned. |
| * </p> |
| * <p> |
| * If no value is specified, or if the specified value could not correctly |
| * be instantiated or did not implement the {@code Clock} interface, then an |
| * instance of {@link SystemClock} is returned. |
| * </p> |
| * |
| * @return a {@code Clock} instance |
| */ |
| public static Clock getClock() { |
| return createClock(); |
| } |
| |
| private static Map<String, Supplier<Clock>> aliases() { |
| final Map<String, Supplier<Clock>> result = new HashMap<>(); |
| result.put("SystemClock", SystemClock::new); |
| result.put("SystemMillisClock", SystemMillisClock::new); |
| result.put("CachedClock", CachedClock::instance); |
| result.put("CoarseCachedClock", CoarseCachedClock::instance); |
| result.put("org.apache.logging.log4j.core.time.internal.CachedClock", CachedClock::instance); |
| result.put("org.apache.logging.log4j.core.time.internal.CoarseCachedClock", CoarseCachedClock::instance); |
| return result; |
| } |
| |
| private static Clock createClock() { |
| final String userRequest = PropertiesUtil.getProperties().getStringProperty(PROPERTY_NAME); |
| if (userRequest == null) { |
| LOGGER.trace("Using default SystemClock for timestamps."); |
| return logSupportedPrecision(new SystemClock()); |
| } |
| final Supplier<Clock> specified = aliases().get(userRequest); |
| if (specified != null) { |
| LOGGER.trace("Using specified {} for timestamps.", userRequest); |
| return logSupportedPrecision(specified.get()); |
| } |
| try { |
| final Clock result = Loader.newCheckedInstanceOf(userRequest, Clock.class); |
| LOGGER.trace("Using {} for timestamps.", result.getClass().getName()); |
| return logSupportedPrecision(result); |
| } catch (final Exception e) { |
| final String fmt = "Could not create {}: {}, using default SystemClock for timestamps."; |
| LOGGER.error(fmt, userRequest, e); |
| return logSupportedPrecision(new SystemClock()); |
| } |
| } |
| |
| private static Clock logSupportedPrecision(final Clock clock) { |
| final String support = clock instanceof PreciseClock ? "supports" : "does not support"; |
| LOGGER.debug("{} {} precise timestamps.", clock.getClass().getName(), support); |
| return clock; |
| } |
| } |