Base de dades de la població estrangera

java.lang.NullPointerException: Cannot invoke "Object.toString()" because the return value of "java.util.Hashtable.get(Object)" is null at EcatCens.distribucioContinentsStd(EcatCens.java:4110) at EcatCens.estudiParametres(EcatCens.java:552) at EcatCens.performTask(EcatCens.java:160) at EcatCens.doGet(EcatCens.java:81) at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:527) at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:614) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:195) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:155) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:483) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:115) at psiprobe.Tomcat10AgentValve.invoke(Tomcat10AgentValve.java:38) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:663) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:344) at org.apache.coyote.ajp.AjpProcessor.service(AjpProcessor.java:431) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:905) at org.apache.tomcat.util.net.Nio2Endpoint$SocketProcessor.doRun(Nio2Endpoint.java:1685) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) at org.apache.tomcat.util.net.AbstractEndpoint.processSocket(AbstractEndpoint.java:1266) at org.apache.tomcat.util.net.Nio2Endpoint$Nio2SocketWrapper$2.completed(Nio2Endpoint.java:634) at org.apache.tomcat.util.net.Nio2Endpoint$Nio2SocketWrapper$2.completed(Nio2Endpoint.java:610) at java.base/sun.nio.ch.Invoker.invokeUnchecked(Invoker.java:129) at java.base/sun.nio.ch.Invoker$2.run(Invoker.java:221) at java.base/sun.nio.ch.AsynchronousChannelGroupImpl$1.run(AsynchronousChannelGroupImpl.java:113) at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1190) at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:63) at java.base/java.lang.Thread.run(Thread.java:840)