Error: server answered with HTTP 500 error code. Response is: Apache Tomcat/6.0.48 - Error report

HTTP Status 500 - Errore nella generazione PDF: null

type Exception report

message Errore nella generazione PDF: null

description The server encountered an internal error that prevented it from fulfilling this request.

exception 

java.lang.RuntimeException: Errore nella generazione PDF: null
	it.cineca.xhtml2pdf.PdfServiceImpl.renderPdf(PdfServiceImpl.java:69)
	it.cineca.xhtml2pdf.Xhtml2PdfServlet.doPost(Xhtml2PdfServlet.java:73)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:643)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:723)

root cause 

java.lang.NullPointerException
	org.xhtmlrenderer.util.XRLog.log(XRLog.java:206)
	org.xhtmlrenderer.util.XRLog.render(XRLog.java:194)
	org.xhtmlrenderer.util.XRLog.render(XRLog.java:190)
	org.xhtmlrenderer.layout.SharedContext.<init>(SharedContext.java:107)
	org.xhtmlrenderer.pdf.ITextRenderer.<init>(ITextRenderer.java:111)
	org.xhtmlrenderer.pdf.ITextRenderer.<init>(ITextRenderer.java:102)
	it.cineca.xhtml2pdf.PdfServiceImpl.renderPdf(PdfServiceImpl.java:59)
	it.cineca.xhtml2pdf.Xhtml2PdfServlet.doPost(Xhtml2PdfServlet.java:73)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:643)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:723)

note The full stack trace of the root cause is available in the Apache Tomcat/6.0.48 logs.

Apache Tomcat/6.0.48