| /* |
| * 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.util; |
| |
| /** |
| * Log4j API Constants. |
| * |
| * @since 2.6.2 |
| */ |
| public final class Constants { |
| /** |
| * {@code true} if we think we are running in a web container, based on the boolean value of system property |
| * "log4j2.is.webapp", or (if this system property is not set) whether the {@code javax.servlet.Servlet} class |
| * is present in the classpath. |
| */ |
| public static final boolean IS_WEB_APP = PropertiesUtil.getProperties().getBooleanProperty( |
| "log4j2.is.webapp", isClassAvailable("javax.servlet.Servlet")); |
| |
| /** |
| * Kill switch for object pooling in ThreadLocals that enables much of the LOG4J2-1270 no-GC behaviour. |
| * <p> |
| * {@code True} for non-{@link #IS_WEB_APP web apps}, disable by setting system property |
| * "log4j2.enable.threadlocals" to "false". |
| * </p> |
| */ |
| public static final boolean ENABLE_THREADLOCALS = !IS_WEB_APP && PropertiesUtil.getProperties().getBooleanProperty( |
| "log4j2.enable.threadlocals", true); |
| |
| public static final int JAVA_MAJOR_VERSION = getMajorVersion(); |
| |
| /** |
| * Determines if a named Class can be loaded or not. |
| * |
| * @param className The class name. |
| * @return {@code true} if the class could be found or {@code false} otherwise. |
| */ |
| private static boolean isClassAvailable(final String className) { |
| try { |
| return LoaderUtil.loadClass(className) != null; |
| } catch (final Throwable e) { |
| return false; |
| } |
| } |
| |
| /** |
| * Prevent class instantiation. |
| */ |
| private Constants() { |
| } |
| |
| private static int getMajorVersion() { |
| final String version = System.getProperty("java.version"); |
| final String[] parts = version.split("-|\\."); |
| boolean isJEP223; |
| try { |
| final int token = Integer.parseInt(parts[0]); |
| isJEP223 = token != 1; |
| if (isJEP223) { |
| return token; |
| } |
| return Integer.parseInt(parts[1]); |
| } catch (final Exception ex) { |
| return 0; |
| } |
| } |
| } |