I am trying to import excel file but it is giving me this error

following are the code of relevant class with its compilation error
public void importAndParseAttendanceFromUtility()
{
int rowsAffected = 0;
Filename fName;
SLTimeImportTable slTimeImportTable;
//below line is giving following error "Variable has not been declared."
ImportUtilityZKK.Import importObj;
importObj = new ImportUtilityZKK.Import();
fileName = importObj.ReadImportConfig(curext(), sessionId(), curUserId());
if (fileName != "")
{
delete_from slTimeImportTable
where slTimeImportTable.UserId == curUserId()
|| slTimeImportTable.SessionId == sessionId();
importObj.ParseAttendanceFile() ;
}
else
{
info("Failed to import records!");
}
}