Error 500: Internal Server Error.

org.apache.jasper.JasperException: An exception occurred processing [vegetazione/dettagli.jsp] at line [33]

30: <%@ page import="java.util.HashSet"%>
31: <%
32: Utente utente = AttributiSessione.getOggetto(pageContext.getSession(), Utente.class);
33: EngineSample cercatoreRilievi = new EngineSample(utente);
34: cercatoreRilievi.setSintetico("false");
35: if(pageContext.getRequest().getParameter("id")!=null){
36: 	cercatoreRilievi.setPattern(pageContext.getRequest().getParameter("id"));


Stacktrace:
	at org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:567)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:456)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:330)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:281)
	at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:710)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:128)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:107)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:165)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:77)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:492)
	at org.apache.catalina.valves.rewrite.RewriteValve.invoke(RewriteValve.java:616)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:113)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:83)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:782)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:72)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:341)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:397)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:1272)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1801)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:946)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:480)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:57)
	at java.base/java.lang.Thread.run(Thread.java:1474)
Caused by: java.lang.NullPointerException: Cannot invoke "it.aspix.anarchive.obj.Utente.getDbAccessibili()" because "utente" is null
	at it.aspix.anarchive.se.SearchEngine.<init>(SearchEngine.java:81)
	at it.aspix.anarchive.se.SearchEngineMap.<init>(SearchEngineMap.java:34)
	at it.aspix.anarchive.se.EngineSample.<init>(EngineSample.java:81)
	at org.apache.jsp.vegetazione.dettagli_jsp._jspService(dettagli_jsp.java:182)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:64)
	at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:710)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:428)
	... 24 more

java.lang.NullPointerException: Cannot invoke "it.aspix.anarchive.obj.Utente.getDbAccessibili()" because "utente" is null
	at it.aspix.anarchive.se.SearchEngine.(SearchEngine.java:81)
	at it.aspix.anarchive.se.SearchEngineMap.(SearchEngineMap.java:34)
	at it.aspix.anarchive.se.EngineSpecimen.(EngineSpecimen.java:55)
	at it.aspix.anarchive.web.herbaria.Cerca.doHtmlService(Cerca.java:81)
	at it.aspix.anarchive.ServizioHttp.chiamaServizio(ServizioHttp.java:159)
	at it.aspix.anarchive.ServizioHttp.doGet(ServizioHttp.java:122)
	at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:622)
	at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:710)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:128)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:107)
	at it.aspix.anarchive.filtri.FCronometro.doFilter(FCronometro.java:43)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:107)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:165)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:77)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:492)
	at org.apache.catalina.valves.rewrite.RewriteValve.invoke(RewriteValve.java:616)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:113)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:83)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:782)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:72)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:341)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:397)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:1272)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1801)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:946)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:480)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:57)
	at java.base/java.lang.Thread.run(Thread.java:1474)