Is it possible to dynamically configure Tomcat?

It can be done partially. By including the Tomcat library into a servlet you can access a lot of internal stuff from Tomcat. You can get access to the real underlying objects instead of using the javax.* facade objects. You would have to learn more about Tomcat to be able to do a lot with it. I suggest you generate the API from the Tomcat source (like I did) and experiment with it.

For example, this is the source I used to obtain all the current active web applications running in Tomcat 3.2.1. I hope this is useful for you.

import java.util.Enumeration;
import java.util.ArrayList;
import javax.servlet.http.*;

import org.apache.tomcat.core.Request;
import org.apache.tomcat.core.FacadeManager;
import org.apache.tomcat.core.Context;
import org.apache.tomcat.core.ContextManager;
import org.apache.tomcat.util.RequestUtil;

public class ContextTree {
	private ContextManager cm;

	public ContextTree(HttpServletRequest request) {
      FacadeManager facadeM = (FacadeManager)request.getAttribute( FacadeManager.FACADE_ATTRIBUTE);

      if (facadeM == null) {
         cm = null;
         return;
      }

      this.cm = facadeM.getRealRequest(request).getContext().getContextManager();
	}

	public WebLink[] getContextNames() {
      ArrayList list = new ArrayList();
   Enumeration e = cm.getContexts();

      while(e.hasMoreElements()) {
         Context c = (Context)e.nextElement();
         if(c.getDocBase().indexOf("ROOT") == -1) {
            WebLink wl = new WebLink(c.getDescription(), c.getDocBase());
            list.add(wl);
         }
      }

      WebLink[] temp = new WebLink[list.size()];
      list.toArray(temp);
      return temp;
	}
}

[Please see the original forum thread for some advice and warnings about this approach. -Alex]