Runtime Dependencies

Some Log4j features depend on external libraries. This page lists the required and optional dependencies.

The Log4j API is a Java module (with a module-info.java). Many of the other jars are also JPMS modules. The characteristics of the modules are:

Artifact Name Module Name Module Characteristics

log4j-api

org.apache.logging.log4j

Module Directive Notes

exports org.apache.logging.log4j

exports org.apache.logging.log4j.message

exports org.apache.logging.log4j.simple

exports org.apache.logging.log4j.spi

exports org.apache.logging.log4j.status

exports org.apache.logging.log4j.util

Some classes in this package are used by the logging implementation and should be considered private. The module info definition may be modified in the future to export these only to the logging implementation.

requires static java.sql

requires static org.osgi.framework

uses org.apache.logging.log4j.spi.Provider

Service that must be provided by the logging implementation.

uses PropertySource

Service that must be provided by the logging implementation.

uses org.apache.logging.log4j.message.ThreadDumpMessage.ThreadInfoFactory

Service that must be provided by the logging implementation.

provides PropertySource with EnvironmentPropertySource, SystemPropertiesPropertySource

log4j-core

org.apache.logging.log4j.core

Module Directive Notes

exports org.apache.logging.log4j.core

exports org.apache.logging.log4j.core.appender

exports org.apache.logging.log4j.core.appender.db

exports org.apache.logging.log4j.core.appender.nosql

exports org.apache.logging.log4j.core.appender.rewrite

exports org.apache.logging.log4j.core.appender.rolling

exports org.apache.logging.log4j.core.appender.rolling.action

exports org.apache.logging.log4j.core.appender.routing

exports org.apache.logging.log4j.core.async

exports org.apache.logging.log4j.core.config

exports org.apache.logging.log4j.core.config.arbiters

exports org.apache.logging.log4j.core.config.builder.api

exports org.apache.logging.log4j.core.config.builder.impl

exports org.apache.logging.log4j.core.config.composite

exports org.apache.logging.log4j.core.config.json

exports org.apache.logging.log4j.core.config.plugins

exports org.apache.logging.log4j.core.config.plugins.convert

exports org.apache.logging.log4j.core.config.plugins.util

exports org.apache.logging.log4j.core.config.plugins.visit

exports org.apache.logging.log4j.core.config.properties

exports org.apache.logging.log4j.core.config.status

exports org.apache.logging.log4j.core.config.xml

exports org.apache.logging.log4j.core.config.yaml

exports org.apache.logging.log4j.core.filter

exports org.apache.logging.log4j.core.impl

exports org.apache.logging.log4j.core.jmx

exports org.apache.logging.log4j.core.layout

exports org.apache.logging.log4j.core.lookup

exports org.apache.logging.log4j.core.message

exports org.apache.logging.log4j.core.net

exports org.apache.logging.log4j.core.net.ssl

exports org.apache.logging.log4j.core.osgi

exports org.apache.logging.log4j.core.parser

exports org.apache.logging.log4j.core.pattern

exports org.apache.logging.log4j.core.script

exports org.apache.logging.log4j.core.selector

exports org.apache.logging.log4j.core.time

exports org.apache.logging.log4j.core.tools

exports org.apache.logging.log4j.core.tools.picocli

exports org.apache.logging.log4j.core.util

exports org.apache.logging.log4j.core.util.datetime

// Required Dependencies

requires transitive org.apache.logging.log4j

requires transitive org.apache.logging.log4j.plugins

// Optional Dependencies

requires static java.desktop

requires static java.management

requires static java.sql

requires static java.rmi

requires static java.xml

requires static com.lmax.disruptor

requires static org.osgi.framework

requires static com.conversantmedia.disruptor

requires static com.fasterxml.jackson.core

requires static com.fasterxml.jackson.databind

requires static com.fasterxml.jackson.dataformat.xml

requires static com.fasterxml.jackson.dataformat.yaml

requires static org.apache.commons.compress

requires static org.fusesource.jansi

requires static jdk.unsupported

uses ContextDataProvider

uses WatchEventService

uses ScriptManagerFactory

provides ThreadInfoFactory with ExtendedThreadInfoFactory

provides ContextDataProvider with ThreadContextDataProvider

provides Provider with Log4jProvider

provides PluginService with Log4jPlugins

provides InjectorCallback with DefaultCallback

log4j-1.2-api

org.apache.log4j

Automatic Module - It is unlikely any application using JPMS would use Log4j 1.x.

log4j-docker

org.apache.logging.log4j.docker

Automatic Module

log4j-flume-ng

org.apache.logging.log4j.flume

Automatic Module

log4j-iostreams

org.apache.logging.log4j.iostreams

Automatic Module

log4j-jpl

org.apache.logging.log4j.jpl

Module Directive Notes

exports org.apache.logging.log4j.jpl to junit

requires org.apache.logging.log4j

requires transitive org.apache.logging.log4j.core

provides java.lang.System.LoggerFinder with org.apache.logging.log4j.jpl.Log4jSystemLoggerFinder

log4j-jul

org.apache.logging.log4j.jul

Module Directive Notes

exports org.apache.logging.log4j.jul

opens org.apache.logging.log4j.jul to org.apache.logging.log4j

requires org.apache.logging.log4j

requires org.apache.logging.log4j.core

requires java.desktop

requires java.logging

log4j-layout-template-json

org.apache.logging.log4j.layout.template.json

Module Directive Notes

exports org.apache.logging.log4j.layout.template.json

exports org.apache.logging.log4j.layout.template.json.resolver

exports org.apache.logging.log4j.layout.template.json.util

opens org.apache.logging.log4j.layout.template.json

opens org.apache.logging.log4j.layout.template.json.resolver

opens org.apache.logging.log4j.layout.template.json.util

requires org.apache.logging.log4j

requires org.apache.logging.log4j.plugins

requires org.apache.logging.log4j.core

log4j-plugin-processor

org.apache.logging.log4j.plugin.processor

Module Directive Notes

exports org.apache.logging.log4j.plugin.processor

requires java.compiler

requires org.apache.logging.log4j

requires org.apache.logging.log4j.plugins

requires transitive org.osgi.framework

provides javax.annotation.processing.Processor with org.apache.logging.log4j.plugin.processor.PluginProcessor

log4j-plugins

org.apache.logging.log4j.plugins

Module Directive Notes

exports org.apache.logging.log4j.plugins

exports org.apache.logging.log4j.plugins.condition

exports org.apache.logging.log4j.plugins.convert

exports org.apache.logging.log4j.plugins.di

exports org.apache.logging.log4j.plugins.model

exports org.apache.logging.log4j.plugins.name

exports org.apache.logging.log4j.plugins.util

exports org.apache.logging.log4j.plugins.validation

exports org.apache.logging.log4j.plugins.validation.constraints

exports org.apache.logging.log4j.plugins.validation.validators

exports org.apache.logging.log4j.plugins.visit

requires org.apache.logging.log4j

requires static org.osgi.framework

uses PluginService

uses InjectorCallback

log4j-script

org.apache.logging.log4j.script

Module Directive Notes

exports org.apache.logging.log4j.script

exports org.apache.logging.log4j.script.appender

opens org.apache.logging.log4j.script.appender to org.apache.logging.log4j.core

exports org.apache.logging.log4j.script.appender.rolling.action

exports org.apache.logging.log4j.script.config.arbiter

opens org.apache.logging.log4j.script.config.arbiter to org.apache.logging.log4j.core

exports org.apache.logging.log4j.script.filter

exports org.apache.logging.log4j.script.layout

opens org.apache.logging.log4j.script.layout to org.apache.logging.log4j.core

exports org.apache.logging.log4j.script.plugins

requires org.apache.logging.log4j

requires org.apache.logging.log4j.core

requires org.apache.logging.log4j.plugins

requires java.scripting

provides PluginService with Log4jPlugins

provides ScriptManagerFactory with ScriptManagerFactoryImpl

log4j-slf4j-impl

org.apache.logging.log4j.slf4j.impl

Automatic Module. May require renaming should SLF4J ever require all implementations to have the same module name.

log4j-to-jul

org.apache.logging.log4j.tojul

Module Directive Notes

exports org.apache.logging.log4j.tojul to org.apache.logging.log4j, org.apache.logging.log4j.tojul.test

requires org.apache.logging.log4j

requires java.logging

provides org.apache.logging.log4j.spi.Provider with org.apache.logging.log4j.tojul.JULProvider

log4j-to-slf4j

org.apache.logging.log4j.slf4j

Automatic Module

log4j-api: The Log4j API module has no required external dependencies.
log4j-core: The Log4j Implementation has no required exterbak dependencies but has several optional dependencies. See the Dependency Tree for the exact list of JAR files needed for these features.

Table 1. Optional Dependencies per Feature in Log4j Implementation
Feature	Requirements
XML configuration	-
Properties configuration	-
JSON configuration	Jackson core and databind
YAML configuration	Jackson databind and YAML data format
CSV Layout	Apache Commons CSV
Async Loggers	LMAX Disruptor
Windows console color support	Jansi
JDBC Appender	a JDBC driver for the database you choose to write events to
NoSQL Appender with MongoDB provider	MongoDB Java Client driver and Log4j MongoDB library
Bzip2, Deflate, Pack200, and XZ compression on rollover	Apache Commons Compress. In addition, XZ requires XZ for Java.
log4j-1.2-api	The Log4j 1.2 Bridge has no external dependencies. This only requires the Log4j API. Including Log4j Core provides optional, extra functionality.
log4j-api-scala	The Log4j Scala API requires Scala runtime library and reflection in addition to the Log4j API.
log4j-docker	Log4j Docker Support requires Jackson annotations, core, and databind. See the Dependency Tree for the exact list of JAR files needed.
log4j-flume-ng	The Flume Appender requires Apache Flume and Apache Avro. The persistent agent uses Berkeley DB. See the Dependency Tree for the exact list of JAR files needed.
log4j-iostreams	The Log4j IO Streams module has no external dependencies. This only requires the Log4j API.
log4j-jmx-gui	The Log4j JMX GUI requires the JConsole jar when run as a JConsole plugin. Otherwise it has no external dependencies. See the Dependency Tree for the exact list of JAR files needed.
log4j-jul	The Log4j 2 Java Util Logging Adapter has no external dependencies. It optionally depends on the Log4j Core library. The only required module is the Log4j API.
log4j-mongodb4	The Log4j MongoDB module depends on the MongoDB Java Client driver.
log4j-slf4j-impl	The Log4j 2 SLF4J Binding depends on the SLF4J API. See the Dependency Tree for the exact list of JAR files needed. WARNING: Do not use this with the log4j-to-slf4j module.
log4j-spring-cloud-config-client	Log4j Spring Cloud Config Client requires Spring Cloud Config. Spring Cloud Bus is required if notification of logging configuration changes is desired. Spring Boot is required but applications do not have to be packaged as a Spring Boot application.
log4j-to-slf4j	The Log4j 2 to SLF4J Adapter requires the SLF4J API and an SLF4J implementation. See the Dependency Tree for the exact list of JAR files needed. WARNING: Do not use this with the log4j-slf4j-impl module.