报错！！！Servlet.service() for servlet [action] in context with path [/myssh] threw exception [java.lang.NullPointerException] with root cause java.lang.NullPointerException

这个为什么报错啊~~

at com.hsp.basic.BasicService.executeQuery(BasicService.java:33)

这个对应的语句是   Query query =this.sessionFactory.getCurrentSession().createQuery(hql);

Sep 24, 2017 11:39:50 PM org.apache.catalina.core.StandardWrapperValve invoke

严重: Servlet.service() for servlet [action] in context with path [/myssh] threw exception [java.lang.NullPointerException] with root cause

java.lang.NullPointerException

at com.hsp.basic.BasicService.executeQuery(BasicService.java:33)

at com.hsp.service.imp.EmployeeService.checkEmployee(EmployeeService.java:81)

at com.hsp.web.action.LoginAction.login(LoginAction.java:54)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:606)

at org.apache.struts.actions.DispatchAction.dispatchMethod(DispatchAction.java:269)

at org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:170)

at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)

at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)

at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)

at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:462)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)

at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)

at com.hsp.web.filter.MyFilter.doFilter(MyFilter.java:23)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:474)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)

at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)

at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783)

at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)

at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:789)

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1437)

at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)

at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)

at java.lang.Thread.run(Thread.java:745)