StandardWrapper

This image depicts some key aspects of the org.apache.catalina.core.StandardWrapper component. As shown, this component extends ContainerBase, marking it as a container. However, a wrapper exists at the lowest level of the container hierarchy, and any attempt to add a child to it will be met with scorn, and an IllegalStateException.

As the web.xml deployment descriptor is parsed, any<servlet> elements within it are converted into StandardWrapper instances and are added as children of the context.

Key members of the StandardWrapper instance include the following:

• a mappings ArrayList which represents the collection of<servlet-mappings> elements in the web.xml file that are associated with this servlet

• a parameters HashMap which holds the servlet's initialization parameters

• a servletClass member that holds the implementation class for the servlet

• a loadOnStartup integer which indicates whether this servlet should be loaded and initialized at context startup.

T...