Need help: JSP can not run,the server encountered an interna

Dear all,

I have written a class to query DB in tamino, which can run well. but when I use JSP or servlet to call this class, no result out. To make it simple, I have written a simple JSP, but it shows HTTP Status 500 error:

exception

org.apache.jasper.JasperException
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:254)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
root cause

java.lang.NullPointerException
at com.softwareag.tamino.api.dom.TaminoResult.(Unknown Source)
at com.softwareag.tamino.api.dom.TaminoClient.getTaminoResult(Unknown Source)
at com.softwareag.tamino.api.dom.TaminoClient.getTaminoResult(Unknown Source)
at com.softwareag.tamino.api.dom.TaminoClient.getResultByPost(Unknown Source)
at com.softwareag.tamino.api.dom.TaminoClient.getVersion(Unknown Source)
at com.softwareag.tamino.api.dom.TaminoClient.setUrl(Unknown Source)
at com.softwareag.tamino.api.dom.TaminoClient.(Unknown Source)

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Anybody can tell me what’s wrong with this? It is caused by my system configuration? Your help will be really really appreacited.