org.apache.logging.log4j.core.config.ConfigurationException: No name attribute provided for Appender layout

Question

I'm using log4j to log into LogOutput.log. I'm getting below error. Can anyone explain the logic. I'm new to logging

'Exception in thread "main" java.lang.ExceptionInInitializerError
Caused by: org.apache.logging.log4j.core.config.ConfigurationException: No name attribute provided for Appender layout
at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationBuilder.createAppender(PropertiesConfigurationBuilder.java:212)
at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationBuilder.build(PropertiesConfigurationBuilder.java:158)
at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationFactory.getConfiguration(PropertiesConfigurationFactory.java:56)
at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationFactory.getConfiguration(PropertiesConfigurationFactory.java:35)
at org.apache.logging.log4j.core.config.ConfigurationFactory$Factory.getConfiguration(ConfigurationFactory.java:532)
at org.apache.logging.log4j.core.config.ConfigurationFactory$Factory.getConfiguration(ConfigurationFactory.java:456)
at org.apache.logging.log4j.core.config.ConfigurationFactory.getConfiguration(ConfigurationFactory.java:318)
at org.apache.logging.log4j.core.LoggerContext.reconfigure(LoggerContext.java:687)
at org.apache.logging.log4j.core.LoggerContext.reconfigure(LoggerContext.java:708)
at org.apache.logging.log4j.core.LoggerContext.start(LoggerContext.java:263)
at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactory.java:153)
at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactory.java:45)
at org.apache.logging.log4j.LogManager.getContext(LogManager.java:194)
at org.apache.logging.log4j.spi.AbstractLoggerAdapter.getContext(AbstractLoggerAdapter.java:138)
at org.apache.logging.log4j.jcl.LogAdapter.getContext(LogAdapter.java:39)
at org.apache.logging.log4j.spi.AbstractLoggerAdapter.getLogger(AbstractLoggerAdapter.java:48)
at org.apache.logging.log4j.jcl.LogFactoryImpl.getInstance(LogFactoryImpl.java:40)
at org.apache.logging.log4j.jcl.LogFactoryImpl.getInstance(LogFactoryImpl.java:55)
at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:655)
at userinterface.PizzaShoppie.<clinit>(PizzaShoppie.java:17)'

here is my properties file

name=LoggerConfigFile

rootlogger.level=DEBUG
rootlogger.appenderRef.file.ref=LoggerAppender

appender.file.name=LoggerAppender
appender.file.type=FILE
appender.file.fileName=log/LogOutput.log

appender.layout.type=PatternLayout
appender.layout.pattern=%d{dd-mmm-yyyy} %level -%m%n

          

Answer 1

TL;DR: replace appender.layout with appender.file.layout.

The purpose of a Log4j 2 configuration file is to build a Configuration object with its tree of subcomponents. Whenever you have a simple JavaBean property like "name" you can use:

<component prefix>.name=My configuration name

For properties that are components you use the syntax:

<component prefix>.<unique identifier>.type=<plugin's name>

to set the property on the component. FileAppender's plugin name is "File", therefore you can write (you use "file" as identifier, but it can be anything, e.g. "1"):

appender.1.type=File

to instantiate it and then you need to configure all JavaBean properties of the FileAppender by prepending the prefix appender.1. to the property name:

appender.1.name=LoggerAppender
appender.1.fileName=log/LogOutput.log
...

The same rules apply to nested components of the appender:

appender.1.layout.type=PatternLayout

and so on recursively.