tomcat refuses to compile occasionally

[Matt Kunze <ku...@optimiz.com>]

I have been running into occassional problems where tomcat will no longer
compile any jsp files. Most of the time this happens while I am editing
the files - it will recompile up to a point and then produce error
messages. I have also seen this happen just by running unchanging pages.
Once the error occurs it will be displayed for any page tomcat tries to
compile. The pages themselves do not seem to be the problem - they have no
syntax  errors and restarting tomcat will display them. So far this is the
only  'workaround' I have found. Does anyone know what is causing this
problem and what I can do to fix it?

Thanks

Matt



here is the entire text of the message:

Internal Servlet Error:

org.apache.jasper.JasperException: Unable to compile class for JSP
	void
org.apache.jasper.servlet.JspServlet.service(javax.servlet.http.HttpServletRequest,
javax.servlet.http.HttpServletResponse)
	void
javax.servlet.http.HttpServlet.service(javax.servlet.ServletRequest,
javax.servlet.ServletResponse)
	void
org.apache.tomcat.core.ServletWrapper.doService(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.core.Handler.service(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.core.ServletWrapper.service(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.core.ContextManager.internalService(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.core.ContextManager.service(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.service.http.HttpConnectionHandler.processConnection(org.apache.tomcat.service.TcpConnection,
java.lang.Object[])
	void
org.apache.tomcat.service.TcpWorkerThread.runIt(java.lang.Object[])
	void org.apache.tomcat.util.ThreadPool$ControlRunnable.run()
	void java.lang.Thread.run()

Root cause:
java.lang.NullPointerException
	void
org.apache.jasper.servlet.JspServlet.service(javax.servlet.http.HttpServletRequest,
javax.servlet.http.HttpServletResponse)
	void
javax.servlet.http.HttpServlet.service(javax.servlet.ServletRequest,
javax.servlet.ServletResponse)
	void
org.apache.tomcat.core.ServletWrapper.doService(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.core.Handler.service(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.core.ServletWrapper.service(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.core.ContextManager.internalService(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.core.ContextManager.service(org.apache.tomcat.core.Request,
org.apache.tomcat.core.Response)
	void
org.apache.tomcat.service.http.HttpConnectionHandler.processConnection(org.apache.tomcat.service.TcpConnection,
java.lang.Object[])
	void
org.apache.tomcat.service.TcpWorkerThread.runIt(java.lang.Object[])
	void org.apache.tomcat.util.ThreadPool$ControlRunnable.run()
	void java.lang.Thread.run()