org.apache.logging.log4j.core
Interface Appender

All Superinterfaces:
LifeCycle
All Known Implementing Classes:
AbstractAppender, AbstractDatabaseAppender, AbstractOutputStreamAppender, AsyncAppender, ConsoleAppender, FailoverAppender, FileAppender, JdbcAppender, JmsQueueAppender, JmsTopicAppender, JpaAppender, RandomAccessFileAppender, RewriteAppender, RollingFileAppender, RollingRandomAccessFileAppender, RoutingAppender, SmtpAppender, SocketAppender, SyslogAppender

public interface Appender
extends LifeCycle

Appends log events. An Appender can contain a Layout if applicable as well as an ErrorHandler. Typical Appender implementations coordinate with an implementation of AbstractManager to handle external resources such as streams, connections, and other shared state. As Appenders are plugins, concrete implementations need to be annotated with Plugin and need to provide a static factory method annotated with PluginFactory.

Most core plugins are written using a related Manager class that handle the actual task of serializing a LogEvent to some output location. For instance, many Appenders can take advantage of the OutputStreamManager class.

It is recommended that Appenders don't do any heavy lifting since there can be many instances of the class being used at any given time. When resources require locking (e.g., through FileLock), it is important to isolate synchronized code to prevent concurrency issues.


Nested Class Summary
 
Nested classes/interfaces inherited from interface org.apache.logging.log4j.core.LifeCycle
LifeCycle.State
 
Method Summary
 void append(LogEvent event)
          Logs a LogEvent using whatever logic this Appender wishes to use.
 ErrorHandler getHandler()
           
 Layout<? extends Serializable> getLayout()
          Returns the Layout used by this Appender if applicable.
 String getName()
          Get the name of this Appender.
 boolean ignoreExceptions()
          Some Appenders need to propagate exceptions back to the application.
 void setHandler(ErrorHandler handler)
           
 
Methods inherited from interface org.apache.logging.log4j.core.LifeCycle
isStarted, isStopped, start, stop
 

Method Detail

append

void append(LogEvent event)
Logs a LogEvent using whatever logic this Appender wishes to use. It is typically recommended to use a bridge pattern not only for the benefits from decoupling an Appender from its implementation, but it is also handy for sharing resources which may require some form of locking.

Parameters:
event - The LogEvent.

getName

String getName()
Get the name of this Appender.

Returns:
name, may be null.

getLayout

Layout<? extends Serializable> getLayout()
Returns the Layout used by this Appender if applicable.

Returns:
the Layout for this Appender or null if none is configured.

ignoreExceptions

boolean ignoreExceptions()
Some Appenders need to propagate exceptions back to the application. When ignoreExceptions is false the AppenderControl will allow the exception to percolate.

Returns:
true if exceptions will be logged but not thrown, false otherwise.

getHandler

ErrorHandler getHandler()

setHandler

void setHandler(ErrorHandler handler)


Copyright © 1999-2014 Apache Software Foundation. All Rights Reserved.
Apache Logging, Apache Log4j, Log4j, Apache, the Apache feather logo, the Apache Logging project logo, and the Apache Log4j logo are trademarks of The Apache Software Foundation.