java.lang.ClassCastException: [Ljava.lang.Object;

Question

I have two functions in my application and after executing queries got an exception

java.lang.ClassCastException: [Ljava.lang.Object; 
java.lang.ClassCastException: [Ljava.lang.Object;
    at org.openmrs.module.scheduler.impl.SchedulerDWR.fetchUserStatus(SchedulerDWR.java:2011)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.directwebremoting.impl.ExecuteAjaxFilter.doFilter(ExecuteAjaxFilter.java:34)
    at org.directwebremoting.impl.DefaultRemoter$1.doFilter(DefaultRemoter.java:428)
    at org.directwebremoting.impl.DefaultRemoter.execute(DefaultRemoter.java:431)
    at org.directwebremoting.impl.DefaultRemoter.execute(DefaultRemoter.java:283)
    at org.directwebremoting.servlet.PlainCallHandler.handle(PlainCallHandler.java:52)
    at org.directwebremoting.servlet.UrlProcessor.handle(UrlProcessor.java:101)
    at org.directwebremoting.servlet.DwrServlet.doPost(DwrServlet.java:146)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:718)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.openmrs.web.MyTimerFilter.doFilter(MyTimerFilter.java:69)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.openmrs.web.filter.GZIPFilter.doFilterInternal(GZIPFilter.java:61)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.openmrs.module.web.filter.ModuleFilterChain.doFilter(ModuleFilterChain.java:77)
    at org.openmrs.module.web.filter.ModuleFilter.doFilter(ModuleFilter.java:59)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.openmrs.web.filter.OpenmrsFilter.doFilterInternal(OpenmrsFilter.java:112)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    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:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:97)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:111)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
    at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:865)
    at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:579)
    at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1555)
    at java.lang.Thread.run(Thread.java:662)

These are functions 1

public int fetchUserStatus(String provider)
{
    try
    {
        SchedulerService hService = (SchedulerService)Context.getService(SchedulerService.class);

        List<ModuleUser> lst=hService.fetchUserStatus(id);

        for(ModuleUser m:lst)//exception  in this line
        {

            int userid=((ModuleUser) m).getUserId();
            if(userid==id)
            {
                status=((ModuleUser) m).getUserStatus();  
                System.out.println("Inside for"+status);
            }
        }

        System.out.println("status update"+status);

        return status;
    }
    catch(Exception e)
    {
        e.printStackTrace();
        return 2;
    }
}

FUNCTION 2

public List<ModuleUser> fetchUserStatus(int id) {
    try
    {
        session=sessionFactory.getCurrentSession();
        SQLQuery m=session.createSQLQuery("select * from users");

        return m.list();        
    }
    catch(Exception e)
    {
        e.printStackTrace();
        return null;
    }
}

Can anyone suggest what is the wrong with the code?

Answer 1

Raw query in this case returns scalar values:

List<Object[]>

where array contains raw columns from result query. Probably you want something like this:

 SQLQuery m=session.createSQLQuery("select * from users").addEntity(ModuleUser.class);

Answer 2

Is ModuleUser a mapped @Entity ? If yes use HQL instead of native query

List<ModuleUser> users = session.createQuery("from ModuleUser").list()

Else if you are forced to native SQL use @aim solution