The Loader Component
Table of Contents
The Loader element represents the web application class loader that will be used to load Java classes and resources for your web application. Such a class loader must follow the requirements of the Servlet Specification, and load classes from the following locations:
- From the
/WEB-INF/classesdirectory inside your web application.
- From JAR files in the
/WEB-INF/libdirectory inside your web application.
- From resources made available by Catalina to all web applications globally.
A Loader element MAY be nested inside a Context component. If it is not included, a default Loader configuration will be created automatically, which is sufficient for most requirements.
For a more in-depth description of the class loader hierarchy that is implemented by Catalina, see the ClassLoader HowTo.
The description below uses the variable name $CATALINA_BASE to refer the base directory against which most relative paths are resolved. If you have not configured Tomcat for multiple instances by setting a CATALINA_BASE directory, then $CATALINA_BASE will be set to the value of $CATALINA_HOME, the directory into which you have installed Tomcat.
All implementations of Loader support the following attributes:
Java class name of the implementation to use. This class must
NOTE - This attribute has been deprecated in Tomcat 9 and will be removed in Tomcat 10. Use the equivalent attribute on the surrounding Context component.
NOTE - The value for this property will be
inherited from the
The standard implementation of Loader is org.apache.catalina.loader.WebappLoader. It supports the following additional attributes (in addition to the common attributes listed above):
Java class name of the
If not specified, the default value is
No components may be nested inside a Loader element.
A loader is associated with the log category based on its classname.