All Classes

Class	Description
AbsoluteTimeDateFormat	Formats a Date in the format "HH:mm:ss,SSS" for example, "15:49:37,459".
AbstractAction	Abstract base class for implementations of Action.
AbstractAppender	Abstract base class for Appenders.
AbstractAppender.Builder<B extends AbstractAppender.Builder<B>>	Subclasses can extend this abstract Builder.
AbstractAsyncExceptionHandler<T>	Default disruptor exception handler for errors that occur in the AsyncLogger background thread.
AbstractBuilder<T>	Base class for Log4j 1 component builders.
AbstractConfiguration	The base Configuration.
AbstractConfigurationAwareLookup	StrLookup that is ConfigurationAware.
AbstractFileAppender<M extends OutputStreamManager>	Abstract File Appender.
AbstractFileAppender.Builder<B extends AbstractFileAppender.Builder<B>>	Builds FileAppender instances.
AbstractFilter	Users should extend this class to implement filters.
AbstractFilter.AbstractFilterBuilder<B extends AbstractFilter.AbstractFilterBuilder<B>>
AbstractFilterable	Enhances a Class by allowing it to contain Filters.
AbstractFilterable.Builder<B extends AbstractFilterable.Builder<B>>	Subclasses can extend this abstract Builder.
AbstractKeyStoreConfiguration	Configuration of the KeyStore
AbstractLayout<T extends java.io.Serializable>	Abstract base class for Layouts.
AbstractLayout.Builder<B extends AbstractLayout.Builder<B>>	Subclasses can extend this abstract Builder.
AbstractLifeCycle	A life cycle to be extended.
AbstractLogEvent	An abstract log event implementation with default values for all methods.
AbstractLogger	Base implementation of a Logger.
AbstractLoggerAdapter	Abstract Logger registry.
AbstractLoggerAdapter<L>	Provides an abstract base class to use for implementing LoggerAdapter.
AbstractLookup	A default lookup for others to extend.
AbstractManager	Abstract base class used to register managers.
AbstractManager.AbstractFactoryData	Implementations should extend this class for passing data between the getManager method and the manager factory class.
AbstractMessageFactory	Provides an abstract superclass for MessageFactory2 implementations with default implementations (and for MessageFactory by extension).
AbstractOutputStreamAppender<M extends OutputStreamManager>	Appends log events as bytes to a byte output stream.
AbstractOutputStreamAppender.Builder<B extends AbstractOutputStreamAppender.Builder<B>>	Subclasses can extend this abstract Builder.
AbstractPathAction	Abstract action for processing files that are accepted by the specified PathFilters.
AbstractPatternConverter	AbstractPatternConverter is an abstract class that provides the formatting functionality that derived classes need.
AbstractPluginVisitor<A extends java.lang.annotation.Annotation>	Base class for PluginVisitor implementations.
AbstractRolloverStrategy
AbstractScript	Container for the language and body of a script.
AbstractSocketManager	Abstract base class for managing sockets.
AbstractStringLayout	Abstract base class for Layouts that result in a String.
AbstractStringLayout.Builder<B extends AbstractStringLayout.Builder<B>>
AbstractStringLayout.Serializer
AbstractStringLayout.Serializer2	Variation of AbstractStringLayout.Serializer that avoids allocating temporary objects.
AbstractStyleNameConverter	Style pattern converter.
AbstractStyleNameConverter.Black	Black style pattern converter.
AbstractStyleNameConverter.Blue	Blue style pattern converter.
AbstractStyleNameConverter.Cyan	Cyan style pattern converter.
AbstractStyleNameConverter.Green	Green style pattern converter.
AbstractStyleNameConverter.Magenta	Magenta style pattern converter.
AbstractStyleNameConverter.Red	Red style pattern converter.
AbstractStyleNameConverter.White	White style pattern converter.
AbstractStyleNameConverter.Yellow	Yellow style pattern converter.
AbstractTriggeringPolicy	Abstract convenience class for triggering policies that extend AbstractLifeCycle and implement TriggeringPolicy.
AbstractWatcher	Watcher for configuration files.
AbstractWatcher.ReconfigurationRunnable	Helper class for triggering a reconfiguration in a background thread.
AbstractWriterAppender<M extends WriterManager>	Appends log events as strings to a writer.
Action	The Action interface should be implemented by any class that performs file system actions for RollingFileAppenders after the close of the active log file.
Activator	OSGi BundleActivator.
Activator	Consider this class private. OSGi bundle activator.
Advertiser
AnsiConverter	Marks classes that implement ANSI escape code conversions.
AnsiEscape	Converts text into ANSI escape sequences.
ApiLogger	Log4j API implementation of the JUL Logger class.
ApiLoggerAdapter	Logger registry implementation using just log4j-api.
Appender	Implement this interface for your own strategies for outputting log statements.
Appender	Appends LogEvents.
AppenderAdapter	Binds a Log4j 1.x Appender to Log4j 2.
AppenderAdmin	Implementation of the AppenderAdminMBean interface.
AppenderAdminMBean	The MBean interface for monitoring and managing an Appender.
AppenderAttachable	Interface for attaching appenders to objects.
AppenderAttachableImpl	Allows Classes to attach Appenders.
AppenderBuilder<T extends Appender>	Define an Appender Builder.
AppenderComponentBuilder	Builder for constructing Appender Components.
AppenderControl	Wraps an Appender with details an appender implementation shouldn't need to know about.
AppenderControlArraySet	Data structure with similar semantics to CopyOnWriteArraySet, but giving direct access to the underlying array.
AppenderLoggingException	Thrown from an appender when a log event could not be written.
AppenderRef	An Appender reference.
AppenderRefComponentBuilder	Assembler for constructing AppenderRef Components.
AppenderSet	A deferred plugin for appenders.
AppenderSet.Builder
AppenderSkeleton	The base class for Appenders in Log4j 1.
AppenderSkeleton.NoOpErrorHandler
AppendersPlugin	An Appender container.
AppenderWrapper	Wraps a Log4j 2 Appender in an empty Log4j 1 Appender so it can be extracted when constructing the configuration.
Arbiter	Interface used to check for portions of the configuration that may be optionally included.
ArrayBlockingQueueFactory<E>	Factory for creating instances of ArrayBlockingQueue.
ArrayPatternConverter	PatternConverters implement this interface to accept an array of objects when formatting.
ArrayUtils	Copied from Apache Commons Lang (including the @since tags.)
Assert	Utility class providing common validation logic.
AsyncAppender	Appends to one or more Appenders asynchronously.
AsyncAppender.Builder<B extends AsyncAppender.Builder<B>>
AsyncAppenderAdmin	Implementation of the AsyncAppenderAdminMBean interface.
AsyncAppenderAdminMBean	The MBean interface for monitoring and managing an AsyncAppender.
AsyncAppenderBuilder	Build an Asynch Appender
AsyncAppenderEventDispatcher
AsynchronouslyFormattable	Annotation that signals to asynchronous logging components that messages of this type can safely be passed to a background thread without calling Message.getFormattedMessage() first.
AsyncLogger	AsyncLogger is a logger designed for high throughput and low latency logging.
AsyncLoggerConfig	Asynchronous Logger object that is created via configuration and can be combined with synchronous loggers.
AsyncLoggerConfig.Builder<B extends AsyncLoggerConfig.Builder<B>>
AsyncLoggerConfig.RootLogger	An asynchronous root Logger.
AsyncLoggerConfig.RootLogger.Builder<B extends AsyncLoggerConfig.RootLogger.Builder<B>>
AsyncLoggerConfigDefaultExceptionHandler	Default disruptor exception handler for errors that occur in the AsyncLogger background thread.
AsyncLoggerConfigDelegate	Encapsulates the mechanism used to log asynchronously.
AsyncLoggerConfigDisruptor	Helper class decoupling the AsyncLoggerConfig class from the LMAX Disruptor library.
AsyncLoggerConfigDisruptor.Log4jEventWrapper	RingBuffer events contain all information necessary to perform the work in a separate thread.
AsyncLoggerConfigDisruptor.Log4jEventWrapperHandler	EventHandler performs the work in a separate thread.
AsyncLoggerContext	LoggerContext that creates AsyncLogger objects.
AsyncLoggerContextSelector	ContextSelector that manages AsyncLoggerContext instances.
AsyncLoggerDefaultExceptionHandler	Default disruptor exception handler for errors that occur in the AsyncLogger background thread.
AsyncLoggerDisruptor	Helper class for async loggers: AsyncLoggerDisruptor handles the mechanics of working with the LMAX Disruptor, and works with its associated AsyncLoggerContext to synchronize the life cycle of the Disruptor and its thread with the life cycle of the context.
AsyncQueueFullMessageUtil	Consider this class private.
AsyncQueueFullPolicy	Policy for deciding whether to discard the event, enqueue it or log the event on the current thread when the queue is full.
AsyncQueueFullPolicyFactory	Creates AsyncQueueFullPolicy instances based on user-specified system properties.
AuthorizationProvider	Interface to be implemented to add an Authorization header to an HTTP request.
AwaitCompletionReliabilityStrategy	ReliabilityStrategy that counts the number of threads that have started to log an event but have not completed yet, and waits for these threads to finish before allowing the appenders to be stopped.
AwaitUnconditionallyReliabilityStrategy	Reliability strategy that sleeps unconditionally for some time before allowing a Configuration to be stopped.
Base64Converter
Base64Util	Base64 encodes Strings.
BasicAsyncLoggerContextSelector	Returns either this Thread's context or the default AsyncLoggerContext.
BasicAuthorizationProvider	Provides the Basic Authorization header to a request.
BasicCommandLineArguments
BasicConfigurator	Configures the package.
BasicContextSelector	Returns either this Thread's context or the default LoggerContext.
BasicThreadInformation	Generates information about the current Thread.
BiConsumer<K,V>	An operation that accepts two input arguments and returns no result.
BlockingQueueFactory<E>	Factory for creating instances of BlockingQueue.
BooleanHolder	Deprecated. Use AtomicReference.
Booleans	Boolean helpers.
BoundedFIFO	Bounded first-in-first-out buffer.
Builder<T>	A marker interface for Log4j 1.x component builders.
Builder<T>	A type of builder that can be used to configure and create a instances using a Java DSL instead of through a configuration file.
BuilderManager
BuiltConfiguration	This is the general version of the Configuration created by the Builder.
BundleContextSelector	ContextSelector for OSGi bundles.
BurstFilter	The BurstFilter is a logging filter that regulates logging traffic.
BurstFilter.Builder
BurstFilter.LogDelay	Delay object to represent each log event that has occurred within the timespan.
ByteBufferDestination	ByteBufferDestination is the destination that Encoders write binary data to.
ByteBufferDestinationHelper	Helper class for ByteBufferDestination implementors.
ByteStreamLogger
CachedClock	Implementation of the Clock interface that tracks the time in a private long field that is updated by a background thread once every millisecond.
CachedDateFormat	CachedDateFormat optimizes the performance of a wrapped DateFormat.
Cancellable	Interface to cancel a Runnable callback.
CaseConverterResolver	Converts the case of string values.
CaseConverterResolver.ErrorHandlingStrategy
CaseConverterResolverFactory	CaseConverterResolver factory.
Category	Implementation of the Category class for compatibility, despite it having been deprecated a long, long time ago.
CategoryKey	CategoryKey is a wrapper for String that apparently accelerated hash table lookup in early JVM's.
CategoryUtil	Delegates to Logger methods implemented by log4j-core if appropriate.
Chars	Consider this class private.
CharStreamLogger
ClassArbiter	Conditional that determines if the specified class is present.
ClassArbiter.Builder
ClassLoaderContextSelector	This ContextSelector chooses a LoggerContext based upon the ClassLoader of the caller.
ClassNamePatternConverter	Formats the class name of the site of the logging request.
CleanableThreadContextMap	Extension service provider interface to implement additional custom MDC behavior for ThreadContext.
Clearable	Clearable objects may be reset to a reusable state.
Clock	Provides the time stamp used in log events.
ClockFactory	Factory for Clock objects.
CloseableThreadContext	Adds entries to the stack or map and them removes them when the object is closed, e.g.
CloseableThreadContext.Instance
Closer	Closes resources.
CloseShieldOutputStream	A delegating OutputStream that does not close its delegate.
CloseShieldWriter
CoarseCachedClock	This Clock implementation is similar to CachedClock.
CommandLine	CommandLine interpreter that uses reflection to initialize an annotated domain object with values obtained from the command line arguments.
CommandLine.Assert	Utility class providing some defensive coding convenience methods.
CommandLine.BuiltIn	Inner class to group the built-in CommandLine.ITypeConverter implementations.
CommandLine.BuiltIn.BigDecimalConverter
CommandLine.BuiltIn.BigIntegerConverter
CommandLine.BuiltIn.BooleanConverter	Converts "true" or "false" to a Boolean.
CommandLine.BuiltIn.ByteConverter	Converts text to a Byte by delegating to Byte.valueOf(String).
CommandLine.BuiltIn.CharacterConverter
CommandLine.BuiltIn.CharSequenceConverter
CommandLine.BuiltIn.CharsetConverter
CommandLine.BuiltIn.DoubleConverter
CommandLine.BuiltIn.FileConverter
CommandLine.BuiltIn.FloatConverter
CommandLine.BuiltIn.InetAddressConverter	Converts text to a InetAddress by delegating to InetAddress.getByName(String).
CommandLine.BuiltIn.IntegerConverter	Converts text to an Integer by delegating to Integer.valueOf(String).
CommandLine.BuiltIn.ISO8601DateConverter	Converts text in yyyy-mm-dd format to a java.util.Date.
CommandLine.BuiltIn.ISO8601TimeConverter	Converts text in any of the following formats to a java.sql.Time: HH:mm, HH:mm:ss, HH:mm:ss.SSS, HH:mm:ss,SSS.
CommandLine.BuiltIn.LongConverter	Converts text to a Long by delegating to Long.valueOf(String).
CommandLine.BuiltIn.PathConverter
CommandLine.BuiltIn.PatternConverter
CommandLine.BuiltIn.ShortConverter	Converts text to a Short by delegating to Short.valueOf(String).
CommandLine.BuiltIn.StringBuilderConverter
CommandLine.BuiltIn.StringConverter
CommandLine.BuiltIn.URIConverter
CommandLine.BuiltIn.URLConverter
CommandLine.BuiltIn.UUIDConverter
CommandLine.Command	Annotate your class with @Command when you want more control over the format of the generated help message.
CommandLine.DefaultExceptionHandler	Default exception handler that prints the exception message to the specified PrintStream, followed by the usage message for the command or subcommand whose input was invalid.
CommandLine.DuplicateOptionAnnotationsException	Exception indicating that multiple fields have been annotated with the same Option name.
CommandLine.ExecutionException	Exception indicating a problem while invoking a command or subcommand.
CommandLine.Help	A collection of methods and inner classes that provide fine-grained control over the contents and layout of the usage help message to display to end users when help is requested or invalid input values were specified.
CommandLine.Help.Ansi	Provides methods and inner classes to support using ANSI escape codes in usage help messages.
CommandLine.Help.Ansi.IStyle	Defines the interface for an ANSI escape sequence.
CommandLine.Help.Ansi.Palette256Color	Defines a palette map of 216 colors: 6 * 6 * 6 cube (216 colors): 16 + 36 * r + 6 * g + b (0 <= r, g, b <= 5).
CommandLine.Help.Ansi.Style	A set of pre-defined ANSI escape code styles and colors, and a set of convenience methods for parsing text with embedded markup style names, as well as convenience methods for converting styles to strings with embedded escape codes.
CommandLine.Help.Ansi.StyledSection
CommandLine.Help.ColorScheme	All usage help message are generated with a color scheme that assigns certain styles and colors to common parts of a usage message: the command name, options, positional parameters and option parameters.
CommandLine.Help.Column	Columns define the width, indent (leading number of spaces in a column before the value) and Overflow policy of a column in a TextTable.
CommandLine.Help.Column.Overflow	Policy for handling text that is longer than the column width: span multiple columns, wrap to the next row, or simply truncate the portion that doesn't fit.
CommandLine.Help.DefaultOptionRenderer	The DefaultOptionRenderer converts Options to five columns of text to match the default TextTable column layout.
CommandLine.Help.DefaultParameterRenderer	The DefaultParameterRenderer converts Parameters to five columns of text to match the default TextTable column layout.
CommandLine.Help.DefaultParamLabelRenderer	DefaultParamLabelRenderer separates option parameters from their options with a separator string, surrounds optional values with '[' and ']' characters and uses ellipses ("...") to indicate that any number of values is allowed for options or parameters with variable arity.
CommandLine.Help.IOptionRenderer	When customizing online help for Option details, a custom IOptionRenderer can be used to create textual representation of an Option in a tabular format: one or more rows, each containing one or more columns.
CommandLine.Help.IParameterRenderer	When customizing online help for Parameters details, a custom IParameterRenderer can be used to create textual representation of a Parameters field in a tabular format: one or more rows, each containing one or more columns.
CommandLine.Help.IParamLabelRenderer	When customizing online usage help for an option parameter or a positional parameter, a custom IParamLabelRenderer can be used to render the parameter name or label to a String.
CommandLine.Help.Layout	Use a Layout to format usage help text for options and parameters in tabular format.
CommandLine.Help.MinimalOptionRenderer	The MinimalOptionRenderer converts Options to a single row with two columns of text: an option name and a description.
CommandLine.Help.MinimalParameterRenderer	The MinimalParameterRenderer converts Parameters to a single row with two columns of text: the parameters label and a description.
CommandLine.Help.ShortestFirst	Sorts short strings before longer strings.
CommandLine.Help.SortByOptionArityAndNameAlphabetically	Sorts Option instances by their max arity first, then their min arity, then delegates to super class.
CommandLine.Help.SortByShortestOptionNameAlphabetically	Sorts Option instances by their name in case-insensitive alphabetic order.
CommandLine.Help.TextTable	Responsible for spacing out CommandLine.Help.Ansi.Text values according to the CommandLine.Help.Column definitions the table was created with.
CommandLine.Help.TextTable.Cell	Helper class to index positions in a Help.TextTable.
CommandLine.IExceptionHandler	Represents a function that can handle a ParameterException that occurred while parsing the command line arguments.
CommandLine.InitializationException	Exception indicating a problem during CommandLine initialization.
CommandLine.IParseResultHandler	Represents a function that can process a List of CommandLine objects resulting from successfully parsing the command line arguments.
CommandLine.ITypeConverter<K>	When parsing command line arguments and initializing fields annotated with @Option or @Parameters, String values can be converted to any type for which a ITypeConverter is registered.
CommandLine.MaxValuesforFieldExceededException	Exception indicating that more values were specified for an option or parameter than its arity allows.
CommandLine.MissingParameterException	Exception indicating that a required parameter was not specified.
CommandLine.MissingTypeConverterException	Exception indicating that an annotated field had a type for which no CommandLine.ITypeConverter was registered.
CommandLine.Option	Annotate fields in your class with @Option and picocli will initialize these fields when matching arguments are specified on the command line.
CommandLine.OverwrittenOptionException	Exception indicating that an option for a single-value option field has been specified multiple times on the command line.
CommandLine.ParameterException	Exception indicating something went wrong while parsing command line options.
CommandLine.ParameterIndexGapException	Exception indicating that there was a gap in the indices of the fields annotated with CommandLine.Parameters.
CommandLine.Parameters	Fields annotated with @Parameters will be initialized with positional parameters.
CommandLine.PicocliException	Base class of all exceptions thrown by picocli.CommandLine.
CommandLine.PositionalParametersSorter
CommandLine.Range	Describes the number of parameters required and accepted by an option or a positional parameter.
CommandLine.RunAll	Command line parse result handler that prints help if requested, and otherwise executes the top-level command and all subcommands as Runnable or Callable.
CommandLine.RunFirst	Command line parse result handler that prints help if requested, and otherwise executes the top-level Runnable or Callable command.
CommandLine.RunLast	Command line parse result handler that prints help if requested, and otherwise executes the most specific Runnable or Callable subcommand.
CommandLine.TraceLevel
CommandLine.Tracer
CommandLine.TypeConversionException	Exception thrown by CommandLine.ITypeConverter implementations to indicate a String could not be converted.
CommandLine.UnmatchedArgumentException	Exception indicating that a command line argument could not be mapped to any of the fields annotated with CommandLine.Option or CommandLine.Parameters.
CommonsCompressAction	Compresses a file using bzip2 compression.
Component	Container for building Configurations.
ComponentBuilder<T extends ComponentBuilder<T>>	Builds arbitrary components and is the base type for the provided components.
CompositeAction	A group of Actions to be executed in sequence.
CompositeConfiguration	A Composite Configuration.
CompositeFilter	Composes and invokes one or more filters.
CompositeFilterComponentBuilder	Wraps multiple Filter Component builders.
CompositeTriggeringPolicy	Triggering policy that wraps other triggering policies.
Configuration	Interface that must be implemented to create a configuration.
ConfigurationAware	Indicates that a class requests the current Configuration to be injected.
ConfigurationBuilder<T extends Configuration>	Interface for building logging configurations.
ConfigurationBuilderFactory	Provides methods to create ConfigurationBuilders.
ConfigurationException	This exception is thrown when an error occurs reading from, parsing, using, or initializing the Log4j 2 configuration.
ConfigurationFactory	Factory class for parsed Configuration objects from a configuration file.
ConfigurationFactory.Factory	Default Factory.
ConfigurationFactoryData	Factory Data that carries a configuration.
ConfigurationFileWatcher	Watcher for configuration files.
ConfigurationListener	Interface used to allow components to be notified when the configuration changes.
ConfigurationScheduler
ConfigurationSource	Represents the source for the logging configuration.
ConfigurationStrSubstitutor	RuntimeStrSubstitutor is a StrSubstitutor which only supports recursive evaluation of lookups.
Configurator	Log4j 1.x Configurator interface.
Configurator	Initializes and configure the Logging system.
ConsoleAppender	Placeholder for Log4j 1.2 Console Appender.
ConsoleAppender	Appends log events to System.out or System.err using a layout specified by the user.
ConsoleAppender.Builder<B extends ConsoleAppender.Builder<B>>	Builds ConsoleAppender instances.
ConsoleAppender.ConsoleManagerFactory	Factory to create the Appender.
ConsoleAppender.FactoryData	Data to pass to factory method.Unable to instantiate
ConsoleAppender.SystemErrStream	An implementation of OutputStream that redirects to the current System.err.
ConsoleAppender.SystemOutStream	An implementation of OutputStream that redirects to the current System.out.
ConsoleAppender.Target	Enumeration of console destinations.
ConsoleAppenderBuilder	Build a Console Appender
Constants	Constants used internally throughout log4j.
Constants	Log4j Constants.
Constants	Constants for the JUL adapter.
Constants	Log4j API Constants.
Constraint	Meta annotation to mark an annotation as a validation constraint.
ConstraintValidator<A extends java.lang.annotation.Annotation>	Interface that Constraint annotations must implement to perform validation logic.
ConstraintValidators	Utility class to locate an appropriate ConstraintValidator implementation for an annotation.
Container	Definition of a Docker Container
ContextAnchor	Anchor for the ThreadContext.
ContextDataFactory	Factory for creating the StringMap instances used to initialize LogEvents' context data.
ContextDataInjector	Responsible for initializing the context data of LogEvents.
ContextDataInjectorFactory	Factory for ContextDataInjectors.
ContextDataProvider	Source of context data to be added to each log event.
ContextMapLookup	Looks up keys from the context.
ContextSelector	Interface used to locate a LoggerContext.
ContextSelectorAdmin	Implementation of the ContextSelectorAdminMBean interface.
ContextSelectorAdminMBean	The MBean interface for monitoring and managing the ContextSelector.
ContextUtil	Delegates to LoggerContext methods implemented by log4j-core if appropriate.
ConverterKeys	Identifies the keys that are associated with a PatternConverter.
CopyOnWrite	Marker interface indicating that the implementing class is a copy-on-write data structure.
CopyOnWriteSortedArrayThreadContextMap	SortedArrayStringMap-based implementation of the ThreadContextMap interface that creates a copy of the data structure on every modification.
Core
CoreContextSelectors
CoreLogger	Log4j Core implementation of the JUL Logger class.
CoreLoggerAdapter	Logger registry implementation that uses log4j-core.
CounterResolver	Resolves a number from an internal counter.
CounterResolver.AtomicBigInteger
CounterResolverFactory	CounterResolver factory.
CountingNoOpAppender	No-Operation Appender that counts events.
CountingQuietWriter	Counts the number of bytes written.
CronExpression	Provides a parser and evaluator for unix-like cron expressions.
CronScheduledFuture<V>
CronTriggeringPolicy	Rolls a file over based on a cron schedule.
CustomLevelComponentBuilder	Assembler for constructing CustomLevel Components.
CustomLevelConfig	Descriptor of a custom Level object that is created via configuration.
CustomLevels	Container for CustomLevelConfig objects.
CustomLoggerGenerator	Wrapper around Generate.CustomLogger.
CyclicBuffer	Holds LoggingEvents for immediate or differed display.
CyclicBuffer<T>	A bounded buffer containing elements of type T.
DailyRollingFileAppenderBuilder	Build a Daily Rolling File Appender
DatagramOutputStream	OutputStream for UDP connections.
DatagramSocketManager	Socket Manager for UDP connections.
DatagramSocketManager.DatagramSocketManagerFactory	Factory to create the DatagramSocketManager.
DatagramSocketManager.FactoryData	Data for the factory.
DateLayout	This abstract layout takes care of all the date related options and formatting work.
DateLookup	Formats the current date or the date in the LogEvent.
DateParser	DateParser is the "missing" interface for the parsing methods of DateFormat.
DatePatternConverter	Converts and formats the event's date in a StringBuilder.
DatePatternConverter.FixedFormatter
DatePatternConverter.Formatter
DatePatternConverter.PatternFormatter
DatePatternConverter.UnixFormatter
DatePatternConverter.UnixMillisFormatter
DatePrinter	DatePrinter is the "missing" interface for the format methods of DateFormat.
DateTimeDateFormat	Formats a Date in the format "dd MMM yyyy HH:mm:ss,SSS" for example, "06 Nov 1994 15:49:37,459".
DateTypeConverter	Utility methods for Date classes.
DefaultAdvertiser	The default advertiser does not do anything.
DefaultAppenderComponentBuilder	Holds the Appender Component attributes and subcomponents.
DefaultAppenderRefComponentBuilder	Holds the Appender Component attributes and subcomponents.
DefaultArbiter	Default Condition for a Select Condition.
DefaultArbiter.Builder
DefaultAsyncQueueFullPolicy	Default router: enqueue the event for asynchronous logging in the background thread, unless the current thread is the background thread and the queue is full (enqueueing would cause a deadlock).
DefaultCategoryFactory
DefaultComponentAndConfigurationBuilder<T extends ComponentBuilder<T>>	Extends DefaultComponentBuilder to specify DefaultConfigurationBuilder<? extends Configuration> as the ConfigurationBuilder type.
DefaultComponentBuilder<T extends ComponentBuilder<T>,CB extends ConfigurationBuilder<? extends Configuration>>	Generic component that captures attributes and Components in preparation for assembling the Appender's Component.
DefaultCompositeFilterComponentBuilder
DefaultConfiguration	The default configuration writes all output to the Console using the default logging level.
DefaultConfigurationBuilder<T extends BuiltConfiguration>
DefaultCustomLevelComponentBuilder
DefaultErrorHandler	The default ErrorHandler implementation falling back to StatusLogger.
DefaultFilterComponentBuilder
DefaultFlowMessageFactory	Default factory for flow messages.
DefaultFlowMessageFactory.AbstractFlowMessage
DefaultFlowMessageFactory.SimpleEntryMessage
DefaultFlowMessageFactory.SimpleExitMessage
DefaultKeyValuePairComponentBuilder
DefaultLayoutComponentBuilder
DefaultLevelConverter	Default implementation of LevelConverter strategy.
DefaultLevelConverter.JulLevelComparator
DefaultLogBuilder	Collects data for a log event and then logs it.
DefaultLogEventFactory	Always creates new LogEvent instances.
DefaultLoggerComponentBuilder
DefaultLoggerContextAccessor	Default implementation using the Core LoggerContext.
DefaultLookupResult	Default internal implementation of LookupResult.
DefaultMergeStrategy	The default merge strategy for composite configurations.
DefaultPropertyComponentBuilder
DefaultReliabilityStrategy	Reliability strategy that assumes reconfigurations will never take place.
DefaultRenderer	The default ObjectRenderer renders objects by calling their toString() method.
DefaultRepositorySelector
DefaultRolloverStrategy	When rolling over, DefaultRolloverStrategy renames files according to an algorithm as described below.
DefaultRolloverStrategy.Builder	Builds DefaultRolloverStrategy instances.
DefaultRootLoggerComponentBuilder
DefaultScriptComponentBuilder
DefaultScriptFileComponentBuilder	Creates a ScriptFile ComponentBuilder.
DefaultShutdownCallbackRegistry	ShutdownRegistrationStrategy that simply uses Runtime.addShutdownHook(Thread).
DefaultShutdownCallbackRegistry.RegisteredCancellable
DefaultThreadContextMap	The actual ThreadContext Map.
DefaultThreadContextStack	A copy-on-write thread-safe variant of org.apache.logging.log4j.spi.ThreadContextStack in which all mutative operations (add, pop, and so on) are implemented by making a fresh copy of the underlying list.
DefaultThrowableRenderer	Default implementation of ThrowableRenderer using Throwable.printStackTrace(PrintWriter).
DeleteAction	Rollover or scheduled action for deleting old log files that are accepted by the specified PathFilters.
DeletingVisitor	FileVisitor that deletes files that are accepted by all PathFilters.
DenyAllFilter	Denies all logging events.
DenyAllFilter	This filter causes all logging events to be dropped.
DenyAllFilter.Builder
DenyAllFilterBuilder	Build a Pattern Layout
DirectFileRolloverStrategy	Created by rgoers on 1/12/17.
DirectWriteRolloverStrategy	When rolling over, DirectWriteRolloverStrategy writes directly to the file as resolved by the file pattern.
DirectWriteRolloverStrategy.Builder	Builds DirectWriteRolloverStrategy instances.
DiscardingAsyncQueueFullPolicy	Discarding router extends the DefaultAsyncQueueFullPolicy by first verifying if the queue is fuller than the specified threshold ratio; if this is the case, log events more specific than the specified threshold level are dropped.
DisruptorUtil	Utility methods for getting Disruptor related configuration.
DockerLookup	Lookups up keys for for a Docker container.
DOMConfigurator	Use this class to initialize the log4j environment using a DOM tree.
DummyNanoClock	Implementation of the NanoClock interface that always returns a fixed value.
DummyRecycler<V>
DummyRecyclerFactory
Duration	Simplified implementation of the ISO-8601 Durations standard.
DynamicThresholdFilter	Compares against a log level that is associated with a context value.
Encoder<T>	Objects implementing the Encoder interface know how to convert an object to some binary representation and write the result to a ByteBuffer, ideally without creating temporary objects.
EncodingPatternConverter	Converter that encodes the output from a pattern using a specified format.
EncodingPatternConverter.EscapeFormat
EndOfBatchPatternConverter	Formats the EndOfBatch.
EndOfBatchResolver	endOfBatch indicator resolver.
EndOfBatchResolverFactory	EndOfBatchResolver factory.
EnglishEnums	Consider this class private.
EntryMessage	Entry flow messages
EnumConverter<E extends java.lang.Enum<E>>	Converts a String into a Enum.
EnvironmentLookup	Looks up keys from environment variables.
EnvironmentPasswordProvider	PasswordProvider implementation that obtains the password value from a system environment variable.
EnvironmentPropertySource	PropertySource implementation that uses environment variables as a source.
EqualsBaseReplacementConverter	Equals pattern converter.
EqualsIgnoreCaseReplacementConverter	Equals ignore case pattern converter.
EqualsReplacementConverter	Equals pattern converter.
ErrorCode	This interface defines commonly encoutered error codes.
ErrorHandler	Appenders may delegate their error handling to ErrorHandlers.
ErrorHandler	Appenders may delegate their error handling to ErrorHandlers.
ErrorHandlerAdapter	Makes a Log4j 1 ErrorHandler usable by a Log4j 2 Appender.
EventAdditionalFieldInterceptor	Interceptor to add additional fields after event template read.
EventLogger	Logs "Events" that are represented as StructuredDataMessage.
EventLookup	Looks up values from the log event.
EventResolver	TemplateResolver specialized for LogEvents.
EventResolverContext	TemplateResolverContext specialized for LogEvents.
EventResolverContext.Builder
EventResolverFactories	Utility class for EventResolverFactory.
EventResolverFactory	TemplateResolverFactory specialized for LogEvents.
EventResolverInterceptor	TemplateResolverInterceptor specialized for LogEvents.
EventResolverInterceptors	Utility class for EventResolverInterceptor.
EventResolverStringSubstitutor	TemplateResolverStringSubstitutor specialized for LogEvents.
EventRootObjectKeyInterceptor	Interceptor to add a root object key to the event template.
EventRoute	Enumeration over the different destinations where a log event can be sent.
ExceptionResolver	Exception resolver.
ExceptionResolverFactory	ExceptionResolver factory.
ExceptionRootCauseResolver	Exception root cause resolver.
ExceptionRootCauseResolverFactory	ExceptionRootCauseResolver factory.
ExcludeChecker	Excludes the listed keys.
ExecutorServices
ExitMessage	Exit flow messages
ExtendedClassInfo	Class and package data used with a StackTraceElement in a ExtendedStackTraceElement.
ExtendedLogger	Extends the Logger interface with methods that facilitate implementing or extending Loggers.
ExtendedLoggerGenerator	Wrapper around Generate.ExtendedLogger.
ExtendedLoggerWrapper	Wrapper class that exposes the protected AbstractLogger methods to support wrapped loggers.
ExtendedStackTraceElement	Wraps and extends the concept of the JRE's final class StackTraceElement by adding more location information.
ExtendedThreadInfoFactory	Factory to create extended thread information.
ExtendedThreadInformation	Provides information on locks and monitors in the thread dump.
ExtendedThrowablePatternConverter	Outputs the Throwable portion of the LoggingEvent as a full stack trace unless this converter's option is 'short', where it just outputs the first line of the trace, or if the number of lines to print is explicitly specified.
ExtensionLanguageMapping
Facility	The facility codes used by the Syslog system.
FailoverAppender	The FailoverAppender will capture exceptions in an Appender and then route the event to a different appender.
FailoversPlugin	The array of failover Appenders.
FallbackErrorHandler	An ErrorHandler with a secondary appender.
FastDateFormat	FastDateFormat is a fast and thread-safe version of SimpleDateFormat.
FastDateParser	FastDateParser is a fast and thread-safe version of SimpleDateFormat.
FastDateParser.CaseInsensitiveTextStrategy	A strategy that handles a text field in the parsing pattern
FastDateParser.CopyQuotedStrategy	A strategy that copies the static or quoted field in the parsing pattern
FastDateParser.ISO8601TimeZoneStrategy
FastDateParser.NumberStrategy	A strategy that handles a number field in the parsing pattern
FastDateParser.PatternStrategy	A strategy to parse a single field from the parsing pattern
FastDateParser.Strategy	A strategy to parse a single field from the parsing pattern
FastDateParser.StrategyAndWidth	Holds strategy and field width
FastDateParser.TimeZoneStrategy	A strategy that handles a timezone field in the parsing pattern
FastDateParser.TimeZoneStrategy.TzInfo
FastDatePrinter	FastDatePrinter is a fast and thread-safe version of SimpleDateFormat.
FastDatePrinter.CharacterLiteral	Inner class to output a constant single character.
FastDatePrinter.DayInWeekField	Inner class to output the numeric day in week.
FastDatePrinter.Iso8601_Rule	Inner class to output a time zone as a number +/-HHMM or +/-HH:MM.
FastDatePrinter.NumberRule	Inner class defining a numeric rule.
FastDatePrinter.PaddedNumberField	Inner class to output a padded number.
FastDatePrinter.Rule	Inner class defining a rule.
FastDatePrinter.StringLiteral	Inner class to output a constant string.
FastDatePrinter.TextField	Inner class to output one of a set of values.
FastDatePrinter.TimeZoneDisplayKey	Inner class that acts as a compound key for time zone names.
FastDatePrinter.TimeZoneNameRule	Inner class to output a time zone name.
FastDatePrinter.TimeZoneNumberRule	Inner class to output a time zone as a number +/-HHMM or +/-HH:MM.
FastDatePrinter.TwelveHourField	Inner class to output the twelve hour field.
FastDatePrinter.TwentyFourHourField	Inner class to output the twenty four hour field.
FastDatePrinter.TwoDigitMonthField	Inner class to output a two digit month.
FastDatePrinter.TwoDigitNumberField	Inner class to output a two digit number.
FastDatePrinter.TwoDigitYearField	Inner class to output a two digit year.
FastDatePrinter.UnpaddedMonthField	Inner class to output an unpadded month.
FastDatePrinter.UnpaddedNumberField	Inner class to output an unpadded number.
FastDatePrinter.WeekYear	Inner class to output the numeric day in week.
FileAppender	FileAppender appends log events to a file.
FileAppender	File Appender.
FileAppender.Builder<B extends FileAppender.Builder<B>>	Builds FileAppender instances.
FileAppenderBuilder	Build a File Appender
FileDatePatternConverter	Formats a date by delegating to DatePatternConverter.
FileExtension	Enumerates over supported file extensions for compression.
FileLocationPatternConverter	Returns the event's line location information in a StringBuilder.
FileManager	Manages actual File I/O for File Appenders.
FileManager.FactoryData	Factory Data.
FileManager.FileManagerFactory	Factory to create a FileManager.
FilePasswordProvider	PasswordProvider that reads password from a file.
FileRenameAction	File rename action.
FileSize	FileSize utility class.
FileUtils	File utilities.
FileWatchdog	Checks every now and then that a certain file has not changed.
FileWatcher	Watches for changes in a File and performs an action when the file is modified.
Filter
Filter	Interface that must be implemented to allow custom event filtering.
Filter.Result	The result that can returned from a filter method call.
Filterable	Interface implemented by Classes that allow filtering to occur.
FilterableComponentBuilder<T extends ComponentBuilder<T>>	Component builder that can add Filters.
FilterAdapter	Binds a Log4j 1.x Filter with Log4j 2.
FilterBuilder	Define a Filter Builder.
FilterComponentBuilder	Assembler for constructing Filter Components.
FilteredObjectInputStream	Extends ObjectInputStream to only allow some built-in Log4j classes and caller-specified classes to be deserialized.
FilterWrapper	This acts as a container for Log4j 2 Filters to be attached to Log4j 1 components.
FixedDateFormat	Custom time formatter that trades flexibility for performance.
FixedDateFormat.FixedFormat	Enumeration over the supported date/time format patterns.
FixedDateFormat.FixedTimeZoneFormat	Fixed time zone formats.
FixedPreciseClock	Implementation of the PreciseClock interface that always returns a fixed time value.
FlowMessage	Flow messages
FlowMessageFactory	Creates flow messages.
Format	The basic methods for performing date formatting.
FormatCache<F extends Format>	FormatCache is a cache and factory for Formats.
FormatCache.MultipartKey	Helper class to hold multi-part Map keys
FormattedMessage	Handles messages that contain a format String.
FormattedMessageFactory	Creates FormattedMessage instances for MessageFactory2 methods (and MessageFactory by extension.)
FormattingInfo	FormattingInfo instances contain the information obtained when parsing formatting modifiers in conversion modifiers.
FormattingInfo	Modifies the output of a pattern converter for a specified minimum and maximum width and alignment.
FormattingInfo	Modifies the output of a pattern converter for a specified minimum and maximum width and alignment.
FullLocationPatternConverter	Format the event's line location information.
GarbageFreeSortedArrayThreadContextMap	SortedArrayStringMap-based implementation of the ThreadContextMap interface that attempts not to create temporary objects.
Generate	Generates source code for custom or extended logger wrappers.
Generate.CustomLogger	Generates source code for custom logger wrappers that only provide convenience methods for the specified custom levels, not for the standard built-in levels.
Generate.ExtendedLogger	Generates source code for extended logger wrappers that provide convenience methods for the specified custom levels, and by extending org.apache.logging.log4j.spi.ExtendedLoggerWrapper, inherit the convenience methods for the built-in levels provided by the Logger interface.
Generate.LevelInfo
Generate.Type
GzCompressAction	Compresses a file using GZ compression.
GzCompressAction.ConfigurableLevelGZIPOutputStream
HexConverter	Converts Strings to hex.
Hierarchy	This class is specialized in retrieving loggers by name and also maintaining the logger hierarchy.
Hierarchy.PrivateLoggerAdapter
Hierarchy.PrivateLogManager	Private LogManager.
HierarchyEventListener	Listen to events occurring within a Hierarchy.
HighlightConverter	Highlight pattern converter.
Holder<V>	Deprecated. Use AtomicReference.
HostConfig
HtmlLayout	Outputs events as rows in an HTML table on an HTML page.
HtmlLayout.Builder
HtmlLayout.FontSize	Possible font sizes
HtmlLayoutBuilder	Build a Pattern Layout
HtmlTextRenderer	TODO Renders an input as HTML output.
HttpAppender	Sends log events over HTTP.
HttpAppender.Builder<B extends HttpAppender.Builder<B>>	Builds HttpAppender instances.
HttpManager
HttpURLConnectionManager
HttpWatcher
IdlePurgePolicy	Policy is purging appenders that were not in use specified time in minutes
IfAccumulatedFileCount	PathCondition that accepts paths after some count threshold is exceeded during the file tree walk.
IfAccumulatedFileSize	PathCondition that accepts paths after the accumulated file size threshold is exceeded during the file tree walk.
IfAll	Composite PathCondition that only accepts objects that are accepted by all component conditions.
IfAny	Composite PathCondition that accepts objects that are accepted by any component conditions.
IfFileName	PathCondition that accepts files for deletion if their relative path matches either a glob pattern or a regular expression.
IfLastModified	PathCondition that accepts paths that are older than the specified duration.
IfNot	Wrapper PathCondition that accepts objects that are rejected by the wrapped component filter.
IncludeChecker	Includes only the listed keys.
IndexedReadOnlyStringMap	An extension of ReadOnlyStringMap that imposes a total ordering on its keys.
IndexedStringMap	An extension of StringMap that imposes a total ordering on its keys.
InputStreamWrapper
Instant	Models a point in time, suitable for event timestamps.
InstantFormatter	A composite Instant formatter trying to employ either FixedDateFormat, FastDateFormat, or DateTimeFormatter in the given order due to performance reasons.
InstantFormatter.Builder
InstantFormatter.Formatter
InstantFormatter.FormatterFactory
InstantFormatter.JavaDateTimeFormatter
InstantFormatter.JavaDateTimeFormatterFactory
InstantFormatter.Log4jFastFormatter
InstantFormatter.Log4jFastFormatterFactory
InstantFormatter.Log4jFixedFormatter
InstantFormatter.Log4jFixedFormatterFactory
IntegerPatternConverter	Formats an integer.
Integers	Helps deal with integers.
InternalAsyncUtil	Helper class providing some async logging-related functionality.
InternalBufferedInputStream	Internal class that exists primarly to allow location calculations to work.
InternalBufferedReader	Internal class that exists primarly to allow location calculations to work.
InternalFilterOutputStream	Internal class that exists primarly to allow location calculations to work.
InternalFilterWriter	Internal class that exists primarily to allow location calculation to work.
InternalInputStream	Internal class that exists primarily to allow location calculation to work.
InternalLoggerReader	Internal class that exists primarily to allow location calculation to work.
InternalOutputStream	Internal class that exists primarily to allow location calculation to work.
InternalPrintStream	Internal class used primarily to allow location calculations to work properly.
InternalPrintWriter	Internal class that exists primarly to allow location calculations to work.
InternalReader	Internal class that exists primarly to allow location calculations to work.
InternalWriter	Internal class that exists primarly to allow location calculations to work.
Interpolator	Proxies all the other StrLookups.
IoBuilder	Builder class to wrap Loggers into Java IO compatible classes.
IOUtils	Copied from Apache Commons IO revision 1686747.
IPAMConfig
ISO8601DateFormat	Formats a Date in the format "yyyy-MM-dd HH:mm:ss,SSS" for example "1999-11-27 15:49:37,459".
JAnsiTextRenderer	Renders an input as ANSI escaped output.
JavaLookup	Looks up keys related to Java: Java version, JRE version, VM version, and so on.
JCToolsBlockingQueueFactory<E>	Factory for creating instances of BlockingQueues backed by JCTools MpscArrayQueue.
JCToolsBlockingQueueFactory.Idle
JCToolsBlockingQueueFactory.MpscBlockingQueue<E>	BlockingQueue wrapper for JCTools multiple producer single consumer array queue.
JCToolsBlockingQueueFactory.WaitStrategy
JdkMapAdapterStringMap	Provides a read-only StringMap view of a Map<String, String>.
JmxRuntimeInputArgumentsLookup	Maps JVM input arguments (but not main arguments) using JMX to acquire JVM arguments.
JndiCloser	Helper class for closing JNDI resources.
JndiContextSelector	This class can be used to define a custom logger repository.
JndiLookup	Looks up keys from JNDI resources.
JndiManager	Manages a JNDI DirContext.
JndiManager.JndiManagerFactory
JsonConfiguration	Creates a Node hierarchy from a JSON file.
JsonConfiguration.ErrorType	The error that occurred.
JsonConfiguration.Status	Status for recording errors.
JsonConfigurationFactory
JsonReader	A simple JSON parser mapping tokens to basic Java types.
JsonReader.Delimiter
JsonTemplateLayout
JsonTemplateLayout.Builder
JsonTemplateLayout.Context
JsonTemplateLayout.EventTemplateAdditionalField
JsonTemplateLayout.EventTemplateAdditionalField.Builder
JsonTemplateLayout.EventTemplateAdditionalField.Format
JsonTemplateLayoutDefaults
JsonUtils	This class is borrowed from Jackson.
JsonWriter	A simple JSON writer with support for common Java data types.
JsonWriter.Builder
JULLogger	Implementation of Logger that's backed by a Logger.
JULLoggerContext	Implementation of Log4j LoggerContext SPI.
JULLoggerContextFactory	Implementation of Log4j LoggerContextFactory SPI.
JULProvider	Bind the Log4j API to JUL.
KeyStoreConfiguration	Configuration of the KeyStore
KeyStoreConfigurationException
KeyValuePair	Key/Value pair configuration item.
KeyValuePair.Builder
KeyValuePairComponentBuilder	Assembler for constructing KeyValuePair Components.
LambdaUtil	Utility class for lambda support.
LaxHostnameVerifier	An HostnameVerifier which accepts everything.
Layout
Layout<T extends java.io.Serializable>	Lays out a LogEvent in different formats.
LayoutAdapter	Class Description goes here.
LayoutBuilder	Define a Layout Builder.
LayoutComponentBuilder	Assembler for constructing Layout Components.
LayoutWrapper	Bridge between the Log4j 1 Layout and a Log4j 2 Layout.
LazyLog4jLogRecord	Extension of LogRecord with lazy get source related methods based on Log4j's StackLocatorUtil.calcLocation(String).
Level	Defines the minimum set of levels recognized by the system, that is OFF, FATAL, ERROR, WARN, INFO, DEBUG and ALL.
Level	Levels used for identifying the severity of an event.
LevelConverter	Strategy interface to convert between custom Log4j Levels and JUL Levels.
LevelMatchFilter	Simple filter based on level matching.
LevelMatchFilter	This filter returns the onMatch result if the logging level in the event matches the specified logging level exactly.
LevelMatchFilter.Builder
LevelMatchFilterBuilder	Build a Level match failter.
LevelPatternConverter	Returns the event's level in a StringBuilder.
LevelPatternConverter.LevelMapLevelPatternConverter
LevelPatternConverter.SimpleLevelPatternConverter
LevelPatternSelector	Selects the pattern to use based on the Level in the LogEvent.
LevelPatternSelector.Builder	Custom MarkerPatternSelector builder.
LevelRangeFilter	This is a very simple filter based on level matching, which can be used to reject messages with priorities outside a certain range.
LevelRangeFilter	This filter returns the onMatch result if the level in the LogEvent is in the range of the configured min and max levels, otherwise it returns onMismatch value .
LevelRangeFilterBuilder	Build a Level match failter.
LevelResolver	Level resolver.
LevelResolverFactory	LevelResolver factory.
LevelTranslator	Utility class to convert between JDK Levels and Log4j 2 Levels.
LifeCycle	All proper Java frameworks implement some sort of object life cycle.
LifeCycle.State	Status of a life cycle like a LoggerContext.
LifeCycle2	Extends the LifeCycle interface.
LineLocationPatternConverter	Returns the event's line location information in a StringBuilder.
LineSeparatorPatternConverter	Formats a line separator.
LinkedTransferQueueFactory<E>	Factory for creating instances of LinkedTransferQueue.
ListChecker	Class Description goes here.
ListChecker.NoopChecker	Does nothing.
LiteralPatternConverter	Formats a string literal.
Loader	Loads resources (or images) from various sources.
Loader	Load resources (or images) from various sources.
LoaderUtil	Consider this class private. Utility class for ClassLoaders.
LoaderUtil.ThreadContextClassLoaderGetter
LoaderUtil.UrlResource	URL and ClassLoader pair.
LocalizedMessage	Provides some level of compatibility with Log4j 1.x and convenience but is not the recommended way to Localize messages.
LocalizedMessageFactory	Creates FormattedMessage instances for MessageFactory2 methods (and MessageFactory by extension.)
LocationAware	Classes that use location information should implement this interface.
LocationAwareLogEventFactory
LocationAwareLogger	Logger that accepts the location of the caller.
LocationAwareReliabilityStrategy	Interface to ensure delivery of log events to the appropriate Appenders while including location information.
LocationInfo	The internal representation of caller location information.
LockingReliabilityStrategy	ReliabilityStrategy that uses read/write locks to prevent the LoggerConfig from stopping while it is in use.
LockingStringBuilderEncoder	Encoder for StringBuilders that locks on the ByteBufferDestination.
Log4j1Configuration	Class Description goes here.
Log4j1ConfigurationConverter	Tool for converting a Log4j 1.x properties configuration file to Log4j 2.x XML configuration file.
Log4j1ConfigurationConverter.CommandLineArguments
Log4j1ConfigurationFactory	Experimental ConfigurationFactory for Log4j 1.2 properties configuration files.
Log4j1ConfigurationParser	Experimental parser for Log4j 1.2 properties configuration files.
Log4j1MdcPatternConverter	Able to handle the contents of the LogEvent's MDC and either output the entire contents of the properties, or to output the value of a specific key within the property bundle when this pattern converter has the option set.
Log4j1NdcPatternConverter	Returns the event's NDC in a StringBuilder.
Log4j1XmlLayout	Port of XMLLayout in Log4j 1.x.
Log4jBridgeHandler	Bridge from JUL to log4j2. This is an alternative to log4j.jul.LogManager (running as complete JUL replacement), especially useful for webapps running on a container for which the LogManager cannot or should not be used. Installation/usage: Declaratively inside JUL's logging.properties: handlers = org.apache.logging.log4j.jul.Log4jBridgeHandler (and typically also: org.apache.logging.log4j.jul.Log4jBridgeHandler.propagateLevels = true ) Note: in a webapp running on Tomcat, you may create a WEB-INF/classes/logging.properties file to configure JUL for this webapp only: configured handlers and log levels affect your webapp only! This file is then the complete JUL configuration, so JUL's defaults (e.g.
Log4jContextFactory	Factory to locate a ContextSelector and then load a LoggerContext.
Log4jEntityResolver	An EntityResolver specifically designed to return log4j.dtd which is embedded within the log4j jar file.
Log4jLog
Log4jLogEvent	Implementation of a LogEvent.
Log4jLogEvent.Builder	LogEvent Builder helper class.
Log4jLogEvent.LogEventProxy	Proxy pattern used to serialize the LogEvent.
Log4jLogger	SLF4J logger implementation that uses Log4j.
Log4jLoggerFactory	Log4j implementation of SLF4J ILoggerFactory interface.
Log4jLookup	Lookup properties of Log4j
Log4jMarker	Log4j/SLF4J Marker type bridge.
Log4jMarkerFactory	Log4j/SLF4J bridge to create SLF4J Markers based on name or based on existing SLF4J Markers.
Log4jMDCAdapter
Log4jProvider	Binding for the Log4j API.
Log4jServletContainerInitializer	In a Servlet 3.0 or newer environment, this initializer is responsible for starting up Log4j logging before anything else happens in application initialization.
Log4jServletContextListener	In environments older than Servlet 3.0, this initializer is responsible for starting up Log4j logging before anything else happens in application initialization.
Log4jServletFilter	This is responsible for the following: Clearing the logger context when the application has finished starting up. Setting the logger context before processing a request and clearing it after processing a request. Setting the logger context when the application is starting to shut down. This filter is a once-per-request filter.
Log4jShutdownOnContextDestroyedListener
Log4jSystemLogger	JPL logger implementation that uses Log4j.
Log4jSystemLoggerAdapter	System.Logger registry implementation using just log4j-api.
Log4jSystemLoggerFinder
Log4jThread	Prefixes thread names with "Log4j2-".
Log4jThreadFactory	Creates Log4jThreads.
Log4jWebInitializerImpl	This class initializes and deinitializes Log4j no matter how the initialization occurs.
Log4jWebLifeCycle	Specifies an interface for initializing and deinitializing Log4j in a Java EE web application.
Log4jWebSupport	Specifies an interface for setting and clearing a thread-bound LoggerContext in a Java EE web application.
LogAdapter	Commons Logging adapter registry.
LogBuilder	Interface for constructing log events before logging them.
LogEvent	Provides contextual information about a logged message.
LogEventAdapter	Converts a Log4j 2 LogEvent into the components needed by a Log4j 1.x LoggingEvent.
LogEventFactory
LogEventListener	Base class for server classes that listen to LogEvents.
LogEventPatternConverter	LoggingEventPatternConverter is a base class for pattern converters that can format information from instances of LoggingEvent.
LogEventWrapper	Exposes a Log4j 1 logging event as a Log4j 2 LogEvent.
LogEventWrapper.ContextDataMap
LogFactoryImpl	Log4j binding for Commons Logging.
LoggableComponentBuilder<T extends ComponentBuilder<T>>	Common component builder for Logger and RootLogger elements.
Logger
Logger	The core implementation of the Logger interface.
Logger	This is the central interface in the log4j package.
Logger.LoggerProxy	Serialization proxy class for Logger.
LoggerAdapter<L>	A basic registry for LoggerContext objects and their associated external Logger classes.
LoggerBufferedInputStream
LoggerBufferedReader
LoggerComponentBuilder	Assembler for constructing Logger Components.
LoggerConfig	Logger object that is created via configuration.
LoggerConfig.Builder<B extends LoggerConfig.Builder<B>>	Builds LoggerConfig instances.
LoggerConfig.LevelAndRefs
LoggerConfig.LoggerConfigPredicate
LoggerConfig.RootLogger	The root Logger.
LoggerConfig.RootLogger.Builder<B extends LoggerConfig.RootLogger.Builder<B>>	Builds LoggerConfig instances.
LoggerConfigAdmin	Implementation of the LoggerConfigAdminMBean interface.
LoggerConfigAdminMBean	The MBean interface for monitoring and managing a LoggerConfig.
LoggerContext	The LoggerContext is the anchor for the logging system.
LoggerContext	Anchor point for logging implementations.
LoggerContextAccessor	Provides access to a Core Logger Context.
LoggerContextAdmin	Implementation of the LoggerContextAdminMBean interface.
LoggerContextAdminMBean	The MBean interface for monitoring and managing a LoggerContext.
LoggerContextFactory	Implemented by factories that create LoggerContext objects.
LoggerContextKey	Deprecated. with no replacement - no longer used
LoggerContextShutdownAware	Interface allowing interested classes to know when a LoggerContext has shutdown - if the LoggerContext implementation provides a way to register listeners.
LoggerContextShutdownEnabled	LoggerContexts implementing this are able register LoggerContextShutdownAware classes.
LoggerFactory	Implement this interface to create new instances of Logger or a sub-class of Logger.
LoggerFields	A LoggerFields container.
LoggerFilterOutputStream	Logs each line written to a pre-defined level.
LoggerFilterWriter	Logs each line written to a pre-defined level.
LoggerFqcnPatternConverter	Formats the Logger FQCN.
LoggerInputStream	Logs each line read to a pre-defined level.
LoggerNameAwareMessage	Message that is interested in the name of the Logger.
LoggerNameLevelRewritePolicy	Rewrites log event levels for a given logger name.
LoggerOutputStream	Logs each line written to a pre-defined level.
LoggerPatternConverter	Formats a logger name.
LoggerPrintStream	Logs each line written to a pre-defined level.
LoggerPrintWriter	Logs each line written to a pre-defined level.
LoggerReader	Logs each line read to a pre-defined level.
LoggerRegistry<T extends ExtendedLogger>	Convenience class to be used by LoggerContext implementations.
LoggerRegistry.ConcurrentMapFactory<T extends ExtendedLogger>	Generates ConcurrentHashMaps for use by the registry to store the Loggers.
LoggerRegistry.MapFactory<T extends ExtendedLogger>	Interface to control the data structure used by the registry to store the Loggers.
LoggerRegistry.WeakMapFactory<T extends ExtendedLogger>	Generates WeakHashMaps for use by the registry to store the Loggers.
LoggerRepository	A LoggerRepository is used to create and retrieve Loggers.
LoggerResolver	Logger resolver.
LoggerResolverFactory	LoggerResolver factory.
Loggers
LoggersPlugin	Container of Logger objects.
LoggerWriter	Logs each line written to a pre-defined level.
LoggingEvent	No-op version of Log4j 1.2 LoggingEvent.
LoggingException	Exception thrown when an error occurs while logging.
LogLog	Logs statements from within Log4j.
LogManager	The main entry point to Log4j 1.
LogManager	Log4j implementation of LogManager.
LogManager	The anchor point for the Log4j logging system.
LogManagerStatus	Keeps track of LogManager initialization status;
LookupResult
LowerLookup	Converts values to lower case.
LowLevelLogUtil	PrintWriter-based logging utility for classes too low level to use StatusLogger.
MainMapLookup	A map-based lookup for main arguments.
MainMapResolver	An index-based resolver for the main() method arguments.
MainMapResolverFactory	MainMapResolver factory.
ManagerFactory<M,T>	Creates Manager objects.
MapAccessor
MapFilter	A Filter that operates on a Map.
MapLookup	A map-based lookup.
MapMessage<M extends MapMessage<M,V>,V>	Represents a Message that consists of a Map.
MapMessage.MapFormat	When set as the format specifier causes the Map to be formatted as XML.
MapMessageJsonFormatter	The default JSON formatter for MapMessages.
MapPatternConverter	Able to handle the contents of the LogEvent's MapMessage and either output the entire contents of the properties in a similar format to the java.util.Hashtable.toString(), or to output the value of a specific key within the Map.
MapResolver	MapMessage resolver.
MapResolverFactory	MapResolver factory.
MapRewritePolicy	This policy rewrites events where the message of the original event implements java.util.Map.
MapRewritePolicy	This policy modifies events by replacing or possibly adding keys and values to the MapMessage.
MapRewritePolicy.Mode	An enumeration to identify whether keys not in the MapMessage should be added or whether only existing keys should be updated.
Marker	Markers are objects that are used to add easily filterable information to log messages.
MarkerFilter	This filter returns the onMatch result if the marker in the LogEvent is the same as or has the configured marker as a parent.
MarkerLookup	Looks-up markers.
MarkerManager	Applications create Markers by using the Marker Manager.
MarkerManager.Log4jMarker	Consider this class private, it is only public to satisfy Jackson for XML and JSON IO.
MarkerPatternConverter	Returns events' full marker string in a StringBuilder.
MarkerPatternSelector	Selects the pattern to use based on the Marker in the LogEvent.
MarkerPatternSelector.Builder	Custom MarkerPatternSelector builder.
MarkerResolver	A Marker resolver.
MarkerResolverFactory	MarkerResolver factory.
MarkerSimpleNamePatternConverter	Appends an event's maker name to a StringBuilder.
MaxLengthConverter	Max length pattern converter.
MDC	This class behaves just like Log4j's MDC would - and so can cause issues with the redeployment of web applications if the Objects stored in the threads Map cannot be garbage collected.
MDCContextMap	Bind the ThreadContextMap to the SLF4J MDC.
MdcPatternConverter	Able to handle the contents of the LogEvent's MDC and either output the entire contents of the properties in a similar format to the java.util.Hashtable.toString(), or to output the value of a specific key within the property bundle when this pattern converter has the option set.
MementoMessage	Consider this class private. MementoMessage is intended to be used when we need to make an immutable copy of a Message without forgetting the original Message.getFormat() and Message.getParameters() values.
MemoryMappedFileAppender	Memory Mapped File Appender.
MemoryMappedFileAppender.Builder<B extends MemoryMappedFileAppender.Builder<B>>	Builds RandomAccessFileAppender instances.
MemoryMappedFileManager	Extends OutputStreamManager but instead of using a buffered output stream, this class maps a region of a file into memory and writes to this memory region.
MemoryMappedFileManager.FactoryData	Factory Data.
MemoryMappedFileManager.MemoryMappedFileManagerFactory	Factory to create a MemoryMappedFileManager.
MemoryPasswordProvider	Simple PasswordProvider implementation that keeps the password char[] array in memory.
MergeStrategy	Merges two configurations together
Message	An interface for various Message implementations that can be logged.
MessageCollectionMessage<T>	A Message that is a collection of Messages.
MessageFactory	Creates messages.
MessageFactory2	Creates messages.
MessageFactory2Adapter	Adapts a legacy MessageFactory to the new MessageFactory2 interface.
MessageFormatMessage	Handles messages that consist of a format string conforming to java.text.MessageFormat.
MessageFormatMessageFactory	Creates FormattedMessage instances for MessageFactory2 methods (and MessageFactory by extension.)
MessageLayout	Formats a LogEvent in its Message form.
MessageParameterResolver	Message parameter (i.e., Message.getParameters()) resolver.
MessageParameterResolver.ParameterConsumerState
MessageParameterResolverFactory	MessageParameterResolver factory.
MessagePatternConverter	Returns the event's rendered message in a StringBuilder.
MessagePatternConverter.FormattedMessagePatternConverter
MessagePatternConverter.RenderingPatternConverter
MessagePatternConverter.SimpleMessagePatternConverter
MessageResolver	Message resolver.
MessageResolverFactory
MessageSupplier	Classes implementing this interface know how to supply Messages.
MethodLocationPatternConverter	Returns the event's line location information in a StringBuilder.
MimeMessageBuilder	Builder for MimeMessage instances.
Mount
MulticastDnsAdvertiser	Advertise an entity via ZeroConf/MulticastDNS and the JmDNS library.
MultiformatMessage	A Message that can render itself in more than one way.
MultiFormatStringBuilderFormattable	A Message that can render itself in more than one way.
MutableInstant	An instantaneous point on the time line, used for high-precision log event timestamps.
MutableLogEvent	Mutable implementation of the LogEvent interface.
MutableThreadContextStack	TODO
NameAbbreviator	NameAbbreviator generates abbreviated logger and class names.
NameAbbreviator	NameAbbreviator generates abbreviated logger and class names.
NameAbbreviator.DropElementAbbreviator	Abbreviator that drops starting path elements.
NameAbbreviator.MaxElementAbbreviator	Abbreviator that drops starting path elements.
NameAbbreviator.MaxElementAbbreviator	Abbreviator that drops starting path elements.
NameAbbreviator.MaxElementAbbreviator.Strategy	When the name is reduced in length by cutting parts, there can be two ways to do it.
NameAbbreviator.NOPAbbreviator	Abbreviator that simply appends full name to buffer.
NameAbbreviator.NOPAbbreviator	Abbreviator that simply appends full name to buffer.
NameAbbreviator.PatternAbbreviator	Pattern abbreviator.
NameAbbreviator.PatternAbbreviator	Pattern abbreviator.
NameAbbreviator.PatternAbbreviatorFragment	Fragment of an pattern abbreviator.
NameAbbreviator.PatternAbbreviatorFragment	Fragment of an pattern abbreviator.
NamedContextSelector	ContextSelectors that have a name.
NamePatternConverter	Abstract base class for other pattern converters which can return only parts of their name.
NameUtil
NanoClock	Provides the high-resolution time stamp used in log events.
NanoTimePatternConverter	Converts and formats the event's nanoTime in a StringBuilder.
NDC	This class does not use generics to provide better source compatibility.
NdcPatternConverter	Returns the event's NDC in a StringBuilder.
NetUtils	Networking-related convenience methods.
Network
NetworkSettings
Node	A Configuration node.
NoMarkerFilter	This filter returns the onMatch result if there is no marker in the LogEvent.
NoMarkerFilter.Builder
NoOpLogger	Dummy version of a java.util.Logger.
NoOpThreadContextMap	ThreadContextMap implementation used when either of system properties disableThreadContextMap or .
NoOpTriggeringPolicy
NOPLogger	No-operation implementation of Logger used by NOPLoggerRepository.
NOPLoggerRepository	No-operation implementation of LoggerRepository which is used when LogManager.repositorySelector is erroneously nulled during class reloading.
NotANumber
NullAppender	A NullAppender never outputs a message to any device.
NullAppender	An Appender that ignores log events.
NullAppenderBuilder	Build a Null Appender
NullConfiguration	This configuration defaults to no logging.
NullEnumeration	An always-empty Enumerator.
NullOutputStream	Writes all data to the famous /dev/null.
ObjectArrayIterator<E>	An Iterator over an array of objects.
ObjectArrayMessage	Handles messages that contain an Object[].
ObjectMessage	Handles messages that contain an Object.
ObjectRenderer	Converts objects to Strings.
ObjectThreadContextMap	Extension service provider interface to allow putting Object values in the ThreadContext.
OnStartupTriggeringPolicy	Triggers a rollover on every restart, but only if the file size is greater than zero.
OptionConverter	A convenience class to convert property values to specific types.
OptionConverter	A convenience class to convert property values to specific types.
OptionConverter.CharMap
OptionHandler	Log4j 1 Interface for dealing with configuration.
Order	Identifies the relative ordering of a ConfigurationFactory plugin.
OrderComparator	Comparator for classes annotated with Order.
OutputStreamAppender	Appends log events to a given output stream using a layout.
OutputStreamAppender.Builder<B extends OutputStreamAppender.Builder<B>>	Builds OutputStreamAppender instances.
OutputStreamAppender.FactoryData	Holds data to pass to factory method.
OutputStreamAppender.OutputStreamManagerFactory	Creates the manager.
OutputStreamManager	Manages an OutputStream so that it can be shared by multiple Appenders and will allow appenders to reconfigure without requiring a new stream.
ParameterConsumer<S>	An operation that accepts two input arguments and returns no result.
ParameterFormatter	Supports parameter formatting as used in ParameterizedMessage and ReusableParameterizedMessage.
ParameterizedMessage	Handles messages that consist of a format string containing '{}' to represent each replaceable token, and the parameters.
ParameterizedMessageFactory	Creates FormattedMessage instances for MessageFactory2 methods (and MessageFactory by extension.)
ParameterizedNoReferenceMessageFactory	Creates FormattedMessage instances for MessageFactory2 methods (and MessageFactory by extension.)
ParameterizedNoReferenceMessageFactory.StatusMessage	Message implementation that only keeps a reference to the error text and the error (if any), not to the message parameters, in order to avoid memory leaks.
ParameterVisitable	Allows message parameters to be iterated over without any allocation or memory copies.
Parser<T>	Parses DOM and properties.
PasswordDecryptor	Decrypt passwords.
PasswordProvider	PasswordProvider implementations are able to produce a password from somewhere.
PathCondition	Filter that accepts or rejects a candidate Path for deletion.
PathSortByModificationTime	PathSorter that sorts path by their LastModified attribute.
PathSorter	Defines the interface of classes that can sort Paths.
PathWithAttributes	Tuple of a Path and BasicFileAttributes, used for sorting.
PatternConverter	PatternConverter is an abtract class that provides the formatting functionality that derived classes need.
PatternConverter	Interface that all PatternConverters must implement.
PatternFormatter
PatternLayout
PatternLayout	A flexible layout configurable with pattern string.
PatternLayout.Builder	Custom PatternLayout builder.
PatternLayout.NoFormatPatternSerializer
PatternLayout.PatternFormatterPatternSerializer
PatternLayout.PatternSelectorSerializer
PatternLayout.PatternSerializer
PatternLayout.PatternSerializerWithReplacement
PatternLayout.SerializerBuilder
PatternLayoutBuilder	Build a Pattern Layout
PatternMatch	PatternMatch configuration item.
PatternMatch.Builder
PatternParser	Most of the work of the PatternLayout class is delegated to the PatternParser class.
PatternParser	Most of the work of the PatternLayout class is delegated to the PatternParser class.
PatternParser.BasicPatternConverter
PatternParser.DatePatternConverter
PatternParser.LiteralPatternConverter
PatternParser.MDCPatternConverter
PatternParser.NamedPatternConverter
PatternParser.ParserState	The states the parser can be in while parsing the pattern.
PatternProcessor	Parses the rollover pattern.
PatternResolver	Resolver delegating to PatternLayout.
PatternResolverFactory	PatternResolver factory.
Patterns	Pattern strings used throughout Log4j.
PatternSelector	Allows different patterns to be used with the PatternLayout based on some selection criteria.
PerformanceSensitive	Indicates that a particular annotated construct was written with certain performance constraints in mind that should be considered when modifying or testing.
PlainTextRenderer	Renders input unchanged.
Plugin	Annotation that identifies a Class as a Plugin.
PluginAliases	Identifies a list of aliases for a Plugin, PluginAttribute, or PluginBuilderAttribute.
PluginAttribute	Identifies a Plugin Attribute and its default value.
PluginAttributeVisitor	PluginVisitor implementation for PluginAttribute.
PluginBuilder	Builder class to instantiate and configure a Plugin object using a PluginFactory method or PluginBuilderFactory builder class.
PluginBuilderAttribute	Marks a field as a Plugin Attribute.
PluginBuilderAttributeVisitor	PluginVisitor for PluginBuilderAttribute.
PluginBuilderFactory	Marks a method as a factory for custom Plugin builders.
PluginCache
PluginConfiguration	Identifies a parameter or field as a Configuration.
PluginConfigurationVisitor	PluginVisitor implementation for PluginConfiguration.
PluginElement	Identifies a parameter as a Plugin and corresponds with an XML element (or equivalent) in configuration files.
PluginElementVisitor	PluginVisitor implementation for PluginElement.
PluginEntry	Memento object for storing a plugin entry to a cache file.
PluginFactory	Identifies a Method as the factory to create the plugin.
PluginManager	Loads and manages all the plugins.
PluginNode	Identifies a Plugin configuration Node.
PluginNodeVisitor	PluginVisitor implementation for PluginNode.
PluginProcessor	Annotation processor for pre-scanning Log4j 2 plugins.
PluginProcessor.PluginAliasesElementVisitor	ElementVisitor to scan the PluginAliases annotation.
PluginProcessor.PluginElementVisitor	ElementVisitor to scan the Plugin annotation.
PluginRegistry	Registry singleton for PluginType maps partitioned by source type and then by category names.
PluginRegistry.PluginTest	A Test that checks to see if each class is annotated with the 'Plugin' annotation.
PluginType<T>	Plugin Descriptor.
PluginUtil	Plugin utilities.
PluginValue	Identifies a parameter as a value.
PluginValueVisitor	PluginVisitor implementation for PluginValue.
PluginVisitor<A extends java.lang.annotation.Annotation>	Visitor strategy for parsing data from a Node, doing any relevant type conversion, and returning a parsed value for that variable.
PluginVisitors	Utility class to locate an appropriate PluginVisitor implementation for an annotation.
PluginVisitorStrategy	Meta-annotation to denote the class name to use that implements PluginVisitor for the annotated annotation.
PortDefinition
PosixViewAttributeAction	File POSIX attribute view action.
PosixViewAttributeAction.Builder	Builder for the POSIX view attribute action.
PreciseClock	Extension of the Clock interface that is able to provide more accurate time information than milliseconds since the epoch.
Priority	Refrain from using this class directly, use the Level class instead.
Priority	The Priority used in the Syslog system.
PrivateSecurityManagerStackTraceUtil	Internal utility to share a fast implementation of #getCurrentStackTrace() with the java 9 implementation of StackLocator.
PrivateSecurityManagerStackTraceUtil.PrivateSecurityManager
ProcessIdPatternConverter
ProcessIdUtil
PropertiesConfiguration	Constructs a configuration based on Log4j 1 properties.
PropertiesConfiguration	Configuration created from a properties file.
PropertiesConfiguration.NameValue
PropertiesConfigurationBuilder	Helper builder for parsing properties files into a PropertiesConfiguration.
PropertiesConfigurationFactory	Configures Log4j from a log4j 1 format properties file.
PropertiesConfigurationFactory	Creates a PropertiesConfiguration from a properties file.
PropertiesLookup	A lookup designed for Properties defined in the configuration.
PropertiesLookup.ConfigurationPropertyResult
PropertiesLookup.ContextPropertyResult
PropertiesPlugin	Handles properties defined in the configuration.
PropertiesPlugin.NullLookup
PropertiesPropertySource	PropertySource backed by a Properties instance.
PropertiesRewritePolicy	This policy modifies events by replacing or possibly adding keys and values to the MapMessage.
PropertiesUtil	Consider this class private.
PropertiesUtil.Environment	Provides support for looking up global configuration properties via environment variables, property files, and system properties, in three variations:
PropertiesUtil.TimeUnit
Property	Represents a key/value pair in the configuration.
PropertyComponentBuilder	Assembler for constructing Property Components.
PropertyConfigurator	Configures Log4j from properties.
PropertyConfigurator.NameValue
PropertyConfigurator.PropertyWatchdog
PropertyFilePropertySource	PropertySource backed by a properties file.
PropertyRewritePolicy	This policy rewrites events by adding a user-specified list of properties to the event.
PropertySetter	General purpose Object property setter.
PropertySetterException	Thrown when an error is encountered whilst attempting to set a property using the PropertySetter utility class.
PropertySource	A source for global configuration properties.
PropertySource.Comparator	Comparator for ordering PropertySource instances by priority.
PropertySource.Util	Utility methods useful for PropertySource implementations.
Protocol	Enumerates the supported protocols.
Provider	Model class for a Log4j 2 provider.
ProviderUtil	Consider this class private. Utility class for Log4j Providers.
ProvisionNode
PurgePolicy	Policy for purging routed appenders
QueueingRecycler<V>
QueueingRecyclerFactory
QuietWriter	QuietWriter does not throw exceptions when things go wrong.
RandomAccessFileAppender	File Appender.
RandomAccessFileAppender.Builder<B extends RandomAccessFileAppender.Builder<B>>	Builds RandomAccessFileAppender instances.
RandomAccessFileManager	Extends OutputStreamManager but instead of using a buffered output stream, this class uses a ByteBuffer and a RandomAccessFile to do the I/O.
RandomAccessFileManager.FactoryData	Factory Data.
RandomAccessFileManager.RandomAccessFileManagerFactory	Factory to create a RandomAccessFileManager.
ReadOnlyStringMap	A read-only collection of String keys mapped to values of arbitrary type.
ReadOnlyStringMapResolver	ReadOnlyStringMap resolver.
ReadOnlyStringMapResolver.LoopContext
ReadOnlyStringMapResolver.LoopMethod
ReadOnlyThreadContextMap	Read-only view of the data structure that implements MDC behavior for ThreadContext.
Reconfigurable	Implemented by Configurations that can be reconfigured at runtime.
Recycler<V>
RecyclerFactories
RecyclerFactory
RecyclerFactoryConverter	The default string (i.e., recycler factory spec) to RecyclerFactory type converter.
ReflectionUtil	Utility class for performing common reflective operations.
RegexFilter	This filter returns the onMatch result if the message matches the regular expression.
RegexReplacement	Replace tokens in the LogEvent message.
RegexReplacementConverter	Replacement pattern converter.
RelativeTimeDateFormat	Formats a Date by printing the number of milliseconds elapsed since construction of the format.
RelativeTimePatternConverter	Returns the relative time in milliseconds since JVM Startup.
ReliabilityStrategy	Interface for objects that know how to ensure delivery of log events to the appropriate appenders, even during and after the configuration has been modified while the system is actively used.
ReliabilityStrategyFactory	Factory for ReliabilityStrategies.
ReloadingPropertyConfigurator
RenderedMessage	Implements object rendering for Log4j 1.x compatibility.
RendererMap	Map class objects to an ObjectRenderer.
RendererSupport
RepeatPatternConverter	Equals pattern converter.
RepositorySelector	The LogManager uses one (and only one) RepositorySelector implementation to select the LoggerRepository for a particular application context.
Required	Marks a plugin builder field or plugin factory parameter as required.
RequiredValidator	Validator that checks an object for emptiness.
ResolverUtil	ResolverUtil is used to locate classes that are available in the/a class path and meet arbitrary conditions.
ResolverUtil.Test	A simple interface that specifies how to test classes to determine if they are to be included in the results produced by the ResolverUtil.
ResourceBundleLookup	Looks up keys from resource bundles.
ReusableLogEventFactory	Garbage-free LogEventFactory that reuses a single mutable log event.
ReusableMessage	Messages implementing this interface are reused between logging calls.
ReusableMessageFactory	Implementation of the MessageFactory interface that avoids allocating temporary objects where possible.
ReusableObjectMessage	Mutable Message wrapper around an Object message.
ReusableParameterizedMessage	Reusable parameterized message.
ReusableSimpleMessage	Mutable Message wrapper around a String message.
RewriteAppender	This Appender allows the logging event to be manipulated before it is processed by other Appenders.
RewriteAppenderBuilder	Build an Asynch Appender
RewritePolicy	This interface is implemented to provide a rewrite strategy for RewriteAppender.
RewritePolicy	Interface to be implemented by components that support modifications to the LogEvent.
RewritePolicyAdapter	Binds a Log4j 1.x RewritePolicy to Log4j 2.
RewritePolicyBuilder	Define a RewritePolicy Builder.
RewritePolicyWrapper	Binds a Log4j 2 RewritePolicy to Log4j 1.
Rfc1349TrafficClass	Enumerates the RFC 1349 TOS field.
Rfc5424Layout	Formats a log event in accordance with RFC 5424.
RingBufferAdmin	Instruments an LMAX Disruptor ring buffer.
RingBufferAdminMBean	The MBean interface for monitoring and managing an LMAX Disruptor ring buffer.
RingBufferLogEvent	When the Disruptor is started, the RingBuffer is populated with event objects.
RingBufferLogEvent.Factory	Creates the events that will be put in the RingBuffer.
RingBufferLogEventHandler	This event handler gets passed messages from the RingBuffer as they become available.
RingBufferLogEventTranslator	This class is responsible for writing elements that make up a log event into the ringbuffer RingBufferLogEvent.
RollingFileAppender	RollingFileAppender extends FileAppender to backup the log files when they reach a certain size.
RollingFileAppender	An appender that writes to files and can roll over at intervals.
RollingFileAppender.Builder<B extends RollingFileAppender.Builder<B>>	Builds FileAppender instances.
RollingFileAppenderBuilder	Build a File Appender
RollingFileManager	The Rolling File Manager.
RollingFileManager.AsyncAction	Performs actions asynchronously.
RollingFileManager.EmptyQueue
RollingFileManager.FactoryData	Factory data.
RollingFileManager.RollingFileManagerFactory	Factory to create a RollingFileManager.
RollingRandomAccessFileAppender	An appender that writes to random access files and can roll over at intervals.
RollingRandomAccessFileAppender.Builder<B extends RollingRandomAccessFileAppender.Builder<B>>
RollingRandomAccessFileManager	Extends RollingFileManager but instead of using a buffered output stream, this class uses a ByteBuffer and a RandomAccessFile to do the I/O.
RollingRandomAccessFileManager.FactoryData	Factory data.
RollingRandomAccessFileManager.RollingRandomAccessFileManagerFactory	Factory to create a RollingRandomAccessFileManager.
RolloverDescription	Description of actions needed to complete rollover.
RolloverDescriptionImpl	Description of actions needed to complete rollover.
RolloverFrequency	Enumeration of rollover frequency values.
RolloverListener	Implementations of this interface that are registered with the RollingFileManager will be notified before and after a rollover occurs.
RolloverStrategy	A RollingPolicy specifies the actions taken on a logging file rollover.
RootLogger	RootLogger sits at the top of the logger hierarchy.
RootLoggerComponentBuilder	Assembler for constructing the root Logger Components.
RootThrowablePatternConverter	Outputs the Throwable portion of the LoggingEvent as a full stack trace unless this converter's option is 'short', where it just outputs the first line of the trace, or if the number of lines to print is explicitly specified.
Route	A Route to an appender.
Routes	Contains the individual Route elements.
Routes.Builder
RoutingAppender	This Appender "routes" between various Appenders, some of which can be references to Appenders defined earlier in the configuration while others can be dynamically created within this Appender as required.
RoutingAppender.Builder<B extends RoutingAppender.Builder<B>>
RoutingAppender.CreatedRouteAppenderControl
RoutingAppender.ReferencedRouteAppenderControl
RoutingAppender.RouteAppenderControl	LOG4J2-2629: PurgePolicy implementations can invoke RoutingAppender.deleteAppender(String) after we have looked up an instance of a target appender but before events are appended, which could result in events not being recorded to any appender.
RuntimeStrSubstitutor	RuntimeStrSubstitutor is a StrSubstitutor which only supports evaluation of top-level lookups.
Scheduled	Annotation that identifies a Class as requiring a Scheduled thread.
Script	Container for the language and body of a script.
ScriptAppenderSelector
ScriptAppenderSelector.Builder	Builds an appender.
ScriptArbiter	Condition that evaluates a script.
ScriptArbiter.Builder
ScriptComponentBuilder	Assembler for constructing Layout Components.
ScriptCondition	A condition of the DeleteAction where a user-provided script selects the files to delete from a provided list.
ScriptFile	Container for the language and body of a script file along with the file location.
ScriptFileComponentBuilder	Assembler for constructing ScriptFile Components.
ScriptFilter	Returns the onMatch result if the script returns True and returns the onMismatch value otherwise.
ScriptManager	Manages the scripts use by the Configuration.
ScriptManager.ScriptRunner
ScriptPatternSelector	Selects the pattern to use based on the result of executing a Script.
ScriptPatternSelector.Builder	Custom ScriptPatternSelector builder.
ScriptRef	Contains a reference to a script defined elsewhere in the configuration.
ScriptsPlugin	A container of Scripts.
SecretKeyProvider	Factory class to provide a SecretKey instance.
SelectArbiter	Class Description goes here.
SelectArbiter.Builder
SequenceNumberPatternConverter	Formats the event sequence number.
SerializedLayout	Deprecated. Java Serialization has inherent security weaknesses, see https://www.owasp.org/index.php/Deserialization_of_untrusted_data .
Server	Creates MBeans to instrument various classes in the log4j class hierarchy.
ServletAppender	Logs using the ServletContext's log method
ServletAppender.Builder<B extends ServletAppender.Builder<B>>
ServletRequestThreadContext
Severity	Severity values used by the Syslog system.
ShutdownCallbackRegistry	Registry used for Runnable shutdown callback instances.
SimpleLayout	Simple-layout.
SimpleLayoutBuilder	Build a Pattern Layout
SimpleLiteralPatternConverter	Formats a string literal without substitution.
SimpleLiteralPatternConverter.Noop
SimpleLiteralPatternConverter.Space
SimpleLiteralPatternConverter.StringValue
SimpleLogger	This is the default logger that is used when no suitable logging implementation is available.
SimpleLoggerContext	A simple LoggerContext implementation.
SimpleLoggerContextFactory	Simple and stateless LoggerContextFactory.
SimpleMessage	The simplest possible implementation of Message.
SimpleMessageFactory	Creates FormattedMessage instances for MessageFactory2 methods (and MessageFactory by extension.)
SizeBasedTriggeringPolicy
SLF4JLogger
SLF4JLoggerContext
SLF4JLoggerContextFactory
SLF4JLoggingException	Exception thrown when the SLF4J adapter encounters a problem.
SLF4JProvider	Bind the Log4j API to SLF4J.
SmtpAppender	Send an e-mail when a specific logging event occurs, typically on errors or fatal errors.
SmtpAppender.Builder
SmtpManager	Manager for sending SMTP events.
SmtpManager.FactoryData	Factory data.
SmtpManager.SMTPManagerFactory	Factory to create the SMTP Manager.
SocketAddress	Plugin to hold a hostname and port (socket address).
SocketAddress.Builder
SocketAppender	An Appender that delivers events over socket connections.
SocketAppender.AbstractBuilder<B extends SocketAppender.AbstractBuilder<B>>	Subclasses can extend this abstract Builder.
SocketAppender.Builder	Builds a SocketAppender.
SocketAppenderBuilder	Build a Console Appender
SocketOptions	Holds all socket options settable via Socket methods.
SocketPerformancePreferences	Holds all socket options settable via Socket.setPerformancePreferences(int, int, int).
SortedArrayStringMap	Consider this class private. Array-based implementation of the ReadOnlyStringMap interface.
SortingVisitor	FileVisitor that sorts files.
Source	Represents the source for the logging configuration as an immutable object.
SourceResolver	Resolver for the StackTraceElement returned by LogEvent.getSource().
SourceResolverFactory	SourceResolver factory.
SslConfiguration	SSL Configuration
SslConfigurationDefaults
SslConfigurationException
SslConfigurationFactory	Creates an SSL configuration from Log4j properties.
SslSocketManager
SslSocketManager.SslFactoryData
SslSocketManager.SslSocketManagerFactory
StackLocator	Consider this class private. Provides various methods to determine the caller class.
StackLocatorUtil	Consider this class private. Provides various methods to determine the caller class.
StackTraceElementResolver	StackTraceElement resolver.
StackTraceElementResolverContext	TemplateResolverContext specialized for StackTraceElements.
StackTraceElementResolverContext.Builder
StackTraceElementResolverFactory	StackTraceElementResolver factory.
StackTraceElementResolverStringSubstitutor	TemplateResolverStringSubstitutor specialized for StackTraceElements.
StackTraceObjectResolver	Exception stack trace to JSON object resolver used by ExceptionResolver.
StackTraceResolver	TemplateResolver specialized for Throwables.
StackTraceStringResolver	Exception stack trace to JSON string resolver used by ExceptionResolver.
StandardLevel	Standard Logging Levels as an enumeration for use internally.
StaticLoggerBinder	SLF4J LoggerFactoryBinder implementation using Log4j.
StaticMarkerBinder	SLF4J MarkerFactoryBinder implementation using Log4j.
StaticMDCBinder
StatusConfiguration	Configuration for setting up StatusConsoleListener instances.
StatusConfiguration.Verbosity	Specifies how verbose the StatusLogger should be.
StatusConsoleListener	StatusListener that writes to the Console.
StatusData	The Status data.
StatusListener	Interface that allows implementers to be notified of events in the logging system.
StatusLogger	Records events that occur in the logging system.
StatusLoggerAdmin	Implementation of the StatusLoggerAdminMBean interface.
StatusLoggerAdminMBean	The MBean interface for monitoring and managing the StatusLogger.
StoreConfiguration<T>
StoreConfigurationException
StringBuilderEncoder	Encoder for StringBuilders that uses ThreadLocals to avoid locking as much as possible.
StringBuilderFormattable	Objects that implement this interface can be converted to text, ideally without allocating temporary objects.
StringBuilders	Consider this class private.
StringBuilderWriter	Writer implementation that outputs to a StringBuilder.
StringEncoder	Encodes Strings to bytes.
StringFormattedMessage	Handles messages that consist of a format string conforming to Formatter.
StringFormatterMessageFactory	Creates FormattedMessage instances for MessageFactory2 methods (and MessageFactory by extension.)
StringLayout	Instantiates the @{link Layout} type for String-based layouts.
StringMap	Exposes methods to add and remove key-value pairs to and from ReadOnlyStringMap.
StringMapMessage	A StringMapMessage typed to String-only values.
StringMatchFilter	Simple filter based on string matching.
StringMatchFilter	This filter returns the onMatch result if the logging level in the event matches the specified logging level exactly.
StringMatchFilter.Builder
StringMatchFilterBuilder	Build a String match filter.
StringParameterParser
StringParameterParser.DoubleQuotedStringValue
StringParameterParser.NullValue
StringParameterParser.Parser
StringParameterParser.State
StringParameterParser.StringValue
StringParameterParser.Value
StringParameterParser.Values
Strings	Consider this class private.
StrLookup	Lookup a String key to a String value.
StrMatcher	A matcher class that can be queried to determine if a character array portion matches.
StrMatcher.CharMatcher	Class used to define a character for matching purposes.
StrMatcher.CharSetMatcher	Class used to define a set of characters for matching purposes.
StrMatcher.NoMatcher	Class used to match no characters.
StrMatcher.StringMatcher	Class used to define a set of characters for matching purposes.
StrMatcher.TrimMatcher	Class used to match whitespace as per trim().
StrSubstitutor	Substitutes variables within a string by values.
StructuredDataCollectionMessage	A collection of StructuredDataMessages.
StructuredDataFilter	Filter based on data in a StructuredDataMessage.
StructuredDataId	The StructuredData identifier.
StructuredDataLookup	Looks up keys from StructuredDataMessage log messages.
StructuredDataMessage	Represents a Message that conforms to an RFC 5424 StructuredData element along with the syslog message.
StructuredDataMessage.Format	Supported formats.
StyleConverter	Style pattern converter.
Supplier<T>	Consider this class private. Classes implementing this interface know how to supply a value.
SyslogAppender	The Syslog Appender.
SyslogAppender.Builder<B extends SyslogAppender.Builder<B>>
SyslogAppenderBuilder	Build a File Appender
SyslogLayout	Formats a log event as a BSD Log record.
SyslogLayout.Builder<B extends SyslogLayout.Builder<B>>	Builds a SyslogLayout.
SystemClock	Implementation of the Clock interface that returns the system time.
SystemMillisClock	Implementation of the Clock interface that returns the system time in millisecond granularity.
SystemNanoClock	Implementation of the NanoClock interface that returns the system nano time.
SystemPropertiesLookup	Looks up keys from system properties.
SystemPropertiesPropertySource	PropertySource backed by the current system properties.
SystemPropertyArbiter	Condition that determines if the specified property is set.
SystemPropertyArbiter.Builder
TcpSocketManager	Manager of TCP Socket connections.
TcpSocketManager.FactoryData	Data for the factory.
TcpSocketManager.HostResolver
TcpSocketManager.TcpSocketManagerFactory<M extends TcpSocketManager,T extends TcpSocketManager.FactoryData>	Factory to create a TcpSocketManager.
TemplateResolver<V>
TemplateResolverConfig	Accessor to the resolver configuration JSON object read from the template.
TemplateResolverContext<V,C extends TemplateResolverContext<V,C>>	Context used to compile a template and passed to template resolver factory creators.
TemplateResolverFactories	Utility class for TemplateResolverFactory.
TemplateResolverFactory<V,C extends TemplateResolverContext<V,C>>	TemplateResolver factory.
TemplateResolverInterceptor<V,C extends TemplateResolverContext<V,C>>	Main TemplateResolver compilation interception interface.
TemplateResolverInterceptors	Utility class for TemplateResolverInterceptor.
TemplateResolvers	Main class for compiling TemplateResolvers from a template.
TemplateResolvers.UnresolvableTemplateResolver
TemplateResolverStringSubstitutor<V>	A contextual StrSubstitutor abstraction.
Terminable	Interface to be implemented by LoggerContext's that provide a shutdown method.
TextEncoderHelper	Helper class to encode text to binary data without allocating temporary objects.
TextRenderer	Renders an input to an output.
ThreadContext	The ThreadContext allows applications to store information either in a Map or a Stack.
ThreadContext.ContextStack	The ThreadContext Stack interface.
ThreadContext.EmptyIterator<E>	An empty iterator.
ThreadContext.EmptyThreadContextStack	An empty read-only ThreadContextStack.
ThreadContextDataInjector	ThreadContextDataInjector contains a number of strategies for copying key-value pairs from the various ThreadContext map implementations into a StringMap.
ThreadContextDataInjector.ForCopyOnWriteThreadContextMap	The ContextDataInjector used when the ThreadContextMap implementation is a copy-on-write StringMap-based data structure.
ThreadContextDataInjector.ForDefaultThreadContextMap	Default ContextDataInjector for the legacy Map<String, String>-based ThreadContext (which is also the ThreadContext implementation used for web applications).
ThreadContextDataInjector.ForGarbageFreeThreadContextMap	The ContextDataInjector used when the ThreadContextMap implementation is a garbage-free StringMap-based data structure.
ThreadContextDataProvider	ContextDataProvider for ThreadContext data.
ThreadContextDataResolver	Mapped Diagnostic Context (MDC), aka.
ThreadContextDataResolverFactory	ThreadContextDataResolver factory.
ThreadContextMap	Service provider interface to implement custom MDC behavior for ThreadContext.
ThreadContextMap2	Extension service provider interface to implement additional custom MDC behavior for ThreadContext.
ThreadContextMapFactory	Creates the ThreadContextMap instance used by the ThreadContext.
ThreadContextMapFilter	Filter based on a value in the Thread Context Map (MDC).
ThreadContextStack	Service provider interface to implement custom NDC behavior for ThreadContext.
ThreadContextStackResolver	Nested Diagnostic Context (NDC), aka.
ThreadContextStackResolverFactory	ThreadContextStackResolver factory.
ThreadDumpMessage	Captures information about all running Threads.
ThreadDumpMessage.BasicThreadInfoFactory	Factory to create basic thread information.
ThreadDumpMessage.ThreadDumpMessageProxy	Proxy pattern used to serialize the ThreadDumpMessage.
ThreadDumpMessage.ThreadInfoFactory	Factory to create Thread information.
ThreadGroupRenderer
ThreadIdPatternConverter	Formats the event thread ID.
ThreadInformation	Interface used to print basic or extended thread information.
ThreadLocalRecycler<V>
ThreadLocalRecyclerFactory
ThreadNameCachingStrategy	Strategy for deciding whether thread name should be cached or not.
ThreadNamePatternConverter	Formats the event thread name.
ThreadPriorityPatternConverter	Formats the event thread priority.
ThreadResolver	Thread resolver.
ThreadResolverFactory	ThreadResolver factory.
ThresholdFilter	This filter returns the onMatch result if the level in the LogEvent is the same or more specific than the configured level and the onMismatch value otherwise.
ThrowableFormatOptions	Contains options which control how a Throwable pattern is formatted.
ThrowableInformation	Log4j's internal representation of throwables.
ThrowablePatternConverter	Outputs the Throwable portion of the LoggingEvent as a full stack trace unless this converter's option is 'short', where it just outputs the first line of the trace, or if the number of lines to print is explicitly specified.
ThrowableProxy	Wraps a Throwable to add packaging information about each stack trace element.
ThrowableProxyHelper	ThrowableProxyHelper provides utilities required to initialize a new ThrowableProxy instance.
ThrowableProxyHelper.CacheEntry	Cached StackTracePackageElement and ClassLoader.
ThrowableProxyRenderer	ThrowableProxyRenderer is an internal utility providing the code to render a ThrowableProxy to a StringBuilder.
ThrowableRenderer	Implemented by classes that render instances of java.lang.Throwable (exceptions and errors) into a string representation.
ThrowableRendererSupport	Implemented by logger repositories that support configurable rendering of Throwables.
Throwables	Helps with Throwable objects.
TimeBasedTriggeringPolicy	Rolls a file over based on time.
TimeBasedTriggeringPolicy.Builder
TimeFilter	Filters events that fall within a specified time period in each day.
Timer	Primarily used in unit tests, but can be used to track elapsed time for a request or portion of any other operation so long as all the timer methods are called on the same thread in which it was started.
Timer.Status
TimestampMessage	Messages that use this interface will cause the timestamp in the message to be used instead of the timestamp in the LogEvent.
TimestampResolver	Timestamp resolver.
TimestampResolver.EpochResolutionRecord
TimestampResolver.EpochResolver
TimestampResolver.PatternResolver
TimestampResolver.PatternResolverContext
TimestampResolverFactory	TimestampResolver factory.
TlsSyslogFrame	Wraps messages that are formatted according to RFC 5425.
Transform	Utility class for transforming strings.
TriConsumer<K,V,S>	An operation that accepts three input arguments and returns no result.
TriggeringEventEvaluator	Implementors decide when to perform an appender specific action.
TriggeringPolicy	A TriggeringPolicy controls the conditions under which rollover occurs.
TruncatingBufferedPrintWriter
TruncatingBufferedWriter
TrustStoreConfiguration	Configuration of the TrustStore
TrustStoreConfigurationException
TTCCLayoutBuilder	Build a Pattern Layout
TypeConverter<T>	Interface for doing automatic String conversion to a specific type.
TypeConverterRegistry	Registry for TypeConverter plugins.
TypeConverters	Collection of basic TypeConverter implementations.
TypeConverters.BigDecimalConverter	Parses a String into a BigDecimal.
TypeConverters.BigIntegerConverter	Parses a String into a BigInteger.
TypeConverters.BooleanConverter	Converts a String into a Boolean.
TypeConverters.ByteArrayConverter	Converts a String into a byte[].
TypeConverters.ByteConverter	Converts a String into a Byte.
TypeConverters.CharacterConverter	Converts a String into a Character.
TypeConverters.CharArrayConverter	Converts a String into a char[].
TypeConverters.CharsetConverter	Converts a String into a Charset.
TypeConverters.ClassConverter	Converts a String into a Class.
TypeConverters.CronExpressionConverter
TypeConverters.DoubleConverter	Converts a String into a Double.
TypeConverters.DurationConverter	Converts a String into a Duration.
TypeConverters.FileConverter	Converts a String into a File.
TypeConverters.FloatConverter	Converts a String into a Float.
TypeConverters.InetAddressConverter	Converts a String into an InetAddress.
TypeConverters.IntegerConverter	Converts a String into a Integer.
TypeConverters.LevelConverter	Converts a String into a Log4j Level.
TypeConverters.LongConverter	Converts a String into a Long.
TypeConverters.PathConverter	Converts a String into a Path.
TypeConverters.PatternConverter	Converts a String into a Pattern.
TypeConverters.SecurityProviderConverter	Converts a String into a Provider.
TypeConverters.ShortConverter	Converts a String into a Short.
TypeConverters.StringConverter	Returns the given String, no conversion takes place.
TypeConverters.UriConverter	Converts a String into a URI.
TypeConverters.UrlConverter	Converts a String into a URL.
TypeConverters.UuidConverter	Converts a String into a UUID.
TypeUtil	Utility class for working with Java Types and derivatives.
Unbox	Utility for preventing primitive parameter values from being auto-boxed.
Unbox.State
Unbox.WebSafeState	State implementation that only puts JDK classes in ThreadLocals, so this is safe to be used from web applications.
UnrecognizedElementHandler	When implemented by an object configured by DOMConfigurator, the handle method will be called when an unrecognized child element is encountered.
UpperLookup	Converts values to upper case.
Uris
UrlConnectionFactory	Constructs an HTTPURLConnection.
UtilLoggingLevel	An extension of the Level class that provides support for java.util.logging Levels.
UuidPatternConverter	Formats the event sequence number.
UuidUtil	Generates a unique ID.
ValidHost	Indicates that a plugin attribute must be a valid host.
ValidHostValidator	Validator that checks an object to verify it is a valid hostname or IP address.
ValidPort	Indicates that a plugin attribute must be a valid port number.
ValidPortValidator	Validator that checks an object to verify it is a valid port number (an integer between 0 and 65535).
VariablesNotEmptyReplacementConverter	VariablesNotEmpty pattern converter.
VectorAppender	Appends logging events to a vector.
Version
Watcher	Watches for changes in a Source and performs an action when it is modified.
WatcherFactory	Creates Watchers of various types.
WatchEventService
WatchManager	Manages FileWatchers.
WatchManager.LocalUUID
WebLoggerContextUtils	Convenience methods for retrieving the LoggerContext associated with a particular ServletContext.
WebLookup
WrappedFileWatcher
WrappedLogger	Wrapper class to ensure proper FQCN support in Logger calls.
WriterAppender	WriterAppender appends log events to a Writer or an OutputStream depending on the user's choice.
WriterAppender	Appends log events to a Writer.
WriterAppender.Builder<B extends WriterAppender.Builder<B>>	Builds WriterAppender instances.
WriterAppender.FactoryData	Holds data to pass to factory method.
WriterAppender.WriterManagerFactory
WriterManager	Manages a Writer so that it can be shared by multiple Appenders and will allow appenders to reconfigure without requiring a new writer.
XmlConfiguration	Class Description goes here.
XmlConfiguration	Creates a Node hierarchy from an XML file.
XmlConfiguration.ConsumerException
XmlConfiguration.ErrorType	The error that occurred.
XmlConfiguration.ParseAction
XmlConfiguration.SAXErrorHandler
XmlConfiguration.Status	Status for recording errors.
XmlConfigurationFactory	Constructs a Configuration usable in Log4j 2 from a Log4j 1 configuration file.
XmlConfigurationFactory	Factory to construct an XmlConfiguration.
XMLWatchdog
ZipCompressAction	Compresses a file using Zip compression.