Loading class using System Classloader in Tomcat

Question

I need to provide a custom implementation of RMIClassLoaderSpi for my application running in Tomcat. However, it seems that this class needs to be loaded using the System Classloader.

Does anyone know of a good way to provide a class to Tomcat such that it can be loaded using the System Classloader?

I'm aware that I can set the shared.loader and server.loader properties, but as far as I can see these wont' affect the System Classloader.

If anyone's interested, this is the code which is forcing the use of the System Classloader in RMIClassLoader:

Class providerClass =
            Class.forName(providerClassName, false,
                  ClassLoader.getSystemClassLoader());

Where providerClass is the name of my custom implementation of RMIClassLoaderSpi .

Answer 1

Looking into this a bit more, it seems that I can modify setenv.sh to set the CLASSPATH variable, which is then propagated to the system classpath.

From catalina.sh:

# Ensure that any user defined CLASSPATH variables are not used on startup,
# but allow them to be specified in setenv.sh, in rare case when it is needed.
CLASSPATH=

if [ -r "$CATALINA_BASE/bin/setenv.sh" ]; then
  . "$CATALINA_BASE/bin/setenv.sh"
elif [ -r "$CATALINA_HOME/bin/setenv.sh" ]; then
  . "$CATALINA_HOME/bin/setenv.sh"
fi

So it looks like this is the "intended" way to do it.