0

Here I have written some code for retrieve the values from database passing some values.

Below is the Action class code:

AttendenceServiceImpl serveceimpl;
  public  ActionForward getStudentInfo(ActionMapping mapping,
            ActionForm form, HttpServletRequest request,
            HttpServletResponse response) {
        System.out.println("-----------------getStudentInfo Start----------------------");



        String category = request.getParameter("categoryVal");
        String classId = request.getParameter("classidVal");
        String sectionId = request.getParameter("sectionidVal");
        System.out.println("----"+category+"---"+classId+"---"+sectionId);

        serveceimpl.getStudentinfo(category,classId,sectionId);

Here Category, classid and section values are coming.

And I'm calling method of service class from Action class.

Below is the Service class code:

public List getStudentinfo(String category, String classId, String sectionId) {
        System.out.println("------------getStudentinfo SERVICE START---------------------");
        List data=mainpage.getStudentinfo(category, classId, sectionId);
        System.out.println("------------getStudentinfo SERVICE END---------------------");
        return data;
    }

But in Action class I'm getting NullPointerException before control enter into the Service class.

Below is the StackTrace:

  -----------------getStudentInfo Start----------------------
----1---1---1

    javax.servlet.ServletException: java.lang.NullPointerException
        at org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:520)
        at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:427)
        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:647)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
        at com.centris.campus.admin.AuthuFilter.doFilter(AuthuFilter.java:232)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
        at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)
    Caused by: java.lang.NullPointerException
        at com.centris.campus.actions.AttendenceAction.getStudentInfo(AttendenceAction.java:58)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.lang.reflect.Method.invoke(Unknown Source)
        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)
        ... 24 more
    Apr 10, 2014 12:44:47 PM org.apache.catalina.core.StandardWrapperValve invoke
    SEVERE: Servlet.service() for servlet [action] in context with path [/e-CampusPro] threw exception [java.lang.NullPointerException] with root cause
    java.lang.NullPointerException
        at com.centris.campus.actions.AttendenceAction.getStudentInfo(AttendenceAction.java:58)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.lang.reflect.Method.invoke(Unknown Source)
        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:647)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
        at com.centris.campus.admin.AuthuFilter.doFilter(AuthuFilter.java:232)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
        at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)

Please give me the solution it is helpful for me.

Improve this question

1 Answer 1

Reset to default
3

serveceimpl should be null here. Please check whether it has a valid value in it. See below

You haven't initialized it

AttendenceServiceImpl serveceimpl;

Improve this answer
Sign up to request clarification or add additional context in comments.

1 Comment

Glad, it helped. You are welcome :) Please accept the answer to close the question. i.e. Click on the tick on the left side of the answer.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.