Tomcat logs its output in a file called catalina.out. Such file contains the output from the server itself and from all the web applications that don't specify an alternative output file.
Different loggers can be used to log web application outputs. The following instructions are for Log4j.
Web Application logging with Log4j
To include log4j logging in your web application add the following dependency to your maven project file:
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.13</version>
<type>jar</type>
<properties>
<war.bundle>true</war.bundle>
</properties>
</dependency>
<dependency>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
<version>1.0.4</version>
<type>jar</type>
<url>http://jakarta.apache.org/commons/logging</url>
<properties>
<war.bundle>true</war.bundle>
</properties>
</dependency>
Overview
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