1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache license, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the license for the specific language governing permissions and 15 * limitations under the license. 16 */ 17 package org.apache.logging.log4j.core.util; 18 19 import java.nio.charset.Charset; 20 import java.nio.charset.StandardCharsets; 21 22 import org.apache.logging.log4j.util.PropertiesUtil; 23 24 /** 25 * Log4j Constants. 26 */ 27 public final class Constants { 28 29 /** 30 * Name of the system property to use to identify the LogEvent factory. 31 */ 32 public static final String LOG4J_LOG_EVENT_FACTORY = "Log4jLogEventFactory"; 33 34 /** 35 * Name of the system property to use to identify the ContextSelector Class. 36 */ 37 public static final String LOG4J_CONTEXT_SELECTOR = "Log4jContextSelector"; 38 39 /** 40 * Property name for the default status (internal log4j logging) level to use if not specified in configuration. 41 */ 42 public static final String LOG4J_DEFAULT_STATUS_LEVEL = "Log4jDefaultStatusLevel"; 43 44 /** 45 * JNDI context name string literal. 46 */ 47 public static final String JNDI_CONTEXT_NAME = "java:comp/env/log4j/context-name"; 48 49 /** 50 * Line separator. 51 */ 52 public static final String LINE_SEPARATOR = PropertiesUtil.getProperties().getStringProperty("line.separator", 53 "\n"); 54 55 /** 56 * Number of milliseconds in a second. 57 */ 58 public static final int MILLIS_IN_SECONDS = 1000; 59 60 /** 61 * Equivalent to StandardCharsets.UTF_8. 62 * 63 * @deprecated Use {@link StandardCharsets#UTF_8}. Will be removed in 2.5. 64 */ 65 @Deprecated 66 public static final Charset UTF_8 = StandardCharsets.UTF_8; 67 68 /** 69 * Supports user request LOG4J2-898 to have the option to format a message in the background thread. 70 */ 71 public static final boolean FORMAT_MESSAGES_IN_BACKGROUND = PropertiesUtil.getProperties().getBooleanProperty( 72 "log4j.format.msg.async", false); 73 74 /** 75 * {@code true} if we think we are running in a web container, based on the boolean value of system property 76 * "log4j2.is.webapp", or (if this system property is not set) whether the {@code javax.servlet.Servlet} class 77 * is present in the classpath. 78 */ 79 public static final boolean IS_WEB_APP = org.apache.logging.log4j.util.Constants.IS_WEB_APP; 80 81 /** 82 * Kill switch for object pooling in ThreadLocals that enables much of the LOG4J2-1270 no-GC behaviour. 83 * <p> 84 * {@code True} for non-{@link #IS_WEB_APP web apps}, disable by setting system property 85 * "log4j2.enable.threadlocals" to "false". 86 * 87 * @since 2.6 88 */ 89 public static final boolean ENABLE_THREADLOCALS = org.apache.logging.log4j.util.Constants.ENABLE_THREADLOCALS; 90 91 /** 92 * Kill switch for garbage-free Layout behaviour that encodes LogEvents directly into 93 * {@link org.apache.logging.log4j.core.layout.ByteBufferDestination}s without creating intermediate temporary 94 * Objects. 95 * <p> 96 * {@code True} by default iff all loggers are asynchronous because system property 97 * {@code Log4jContextSelector} is set to {@code org.apache.logging.log4j.core.async.AsyncLoggerContextSelector}. 98 * Disable by setting system property "log4j2.enable.direct.encoders" to "false". 99 * 100 * @since 2.6 101 */ 102 public static final boolean ENABLE_DIRECT_ENCODERS = PropertiesUtil.getProperties().getBooleanProperty( 103 "log4j2.enable.direct.encoders", true); // enable GC-free text encoding by default 104 // the alternative is to enable GC-free encoding only by default only when using all-async loggers: 105 //AsyncLoggerContextSelector.class.getName().equals(PropertiesUtil.getProperties().getStringProperty(LOG4J_CONTEXT_SELECTOR))); 106 107 /** 108 * Initial StringBuilder size used in RingBuffer LogEvents to store the contents of reusable Messages. 109 * <p> 110 * The default value is {@value}, users can override with system property "log4j.initialReusableMsgSize". 111 * </p> 112 * @since 2.6 113 */ 114 public static final int INITIAL_REUSABLE_MESSAGE_SIZE = size("log4j.initialReusableMsgSize", 128); 115 116 /** 117 * Maximum size of the StringBuilders used in RingBuffer LogEvents to store the contents of reusable Messages. 118 * After a large message has been delivered to the appenders, the StringBuilder is trimmed to this size. 119 * <p> 120 * The default value is {@value}, which allows the StringBuilder to resize three times from its initial size. 121 * Users can override with system property "log4j.maxReusableMsgSize". 122 * </p> 123 * @since 2.6 124 */ 125 public static final int MAX_REUSABLE_MESSAGE_SIZE = size("log4j.maxReusableMsgSize", (128 * 2 + 2) * 2 + 2); 126 127 /** 128 * Size of CharBuffers used by text encoders. 129 * <p> 130 * The default value is {@value}, users can override with system property "log4j.encoder.charBufferSize". 131 * </p> 132 * @since 2.6 133 */ 134 public static final int ENCODER_CHAR_BUFFER_SIZE = size("log4j.encoder.charBufferSize", 2048); 135 136 /** 137 * Default size of ByteBuffers used to encode LogEvents without allocating temporary objects. 138 * <p> 139 * The default value is {@value}, users can override with system property "log4j.encoder.byteBufferSize". 140 * </p> 141 * @see org.apache.logging.log4j.core.layout.ByteBufferDestination 142 * @since 2.6 143 */ 144 public static final int ENCODER_BYTE_BUFFER_SIZE = size("log4j.encoder.byteBufferSize", 8 * 1024); 145 146 147 private static int size(final String property, final int defaultValue) { 148 return PropertiesUtil.getProperties().getIntegerProperty(property, defaultValue); 149 } 150 151 /** 152 * Prevent class instantiation. 153 */ 154 private Constants() { 155 } 156 }