Unless explicitly compiled ahead of time, JSP files are compiled the first time they are accessed. On large production sites, or in situations involving complicated JSP files, compilation may cause unacceptable delays to users first accessing the JSP page.

Resin provides a JspPrecompileListener that causes jsp to be compiled when the web application starts. As an alternative, Resin also provides a JspCompiler that is used to explicitly compile jsp files before they are accessed for the first time.

is a ServletContextListener that compiles jsp files when the web-app starts. It is activated using the <listener> Servlet configuration tag in web.xml.

The following configuration causes Resin to compile all files in the web-app that have an extension of .jsp or .jspx when the application first starts.

<web-app xmlns="http://caucho.com/ns/resin"> <listener> <listener-class>com.caucho.jsp.JspPrecompileListener</listener-class> <init> <extension>jsp</extension> <extension>jspx</extension> </init> </listener> </web-app>

It can also be configured in resin.conf to apply to all web-app's.

<web-app-default> <listener> <listener-class>com.caucho.jsp.JspPrecompileListener</listener-class> <init> <extension>jsp</extension> <extension>jspx</extension> <extension>xtp</extension> </init> </listener> </web-app-default>

You can also use a for more control over which jsp are precompiled:

<web-app> <listener> <listener-class>com.caucho.jsp.JspPrecompileListener</listener-class> <init> <fileset> <include>**/*.jsp</include> <exclude>/a.jsp</exclude> <exclude>/foo/c.jsp</exclude> </fileset> </init> </listener> </web-app> The first line includes all jsp's, it's the same as specifying jsp. The following lines exclude specific jsp.