showing null point exception when findAllBy - for session object

Question

I have already checked that session.parent_id and session.id_of_project is not null in the below code in gsp

        <g:if test="$session.parent_id">
        <g:set var="permission" value="${Project_permission.findAllById_of_projectAndParent_id(session.id_of_project, session.parent_id)}"/>

        <g:each var="emp" in="${permission}">

          <g:set var="employee2" value="${Employee.findById(emp.id_of_employee)}"/>
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            </li>
          </g:each>
          </g:if>              

But it keep on showing:

Error 500: Internal Server Error java.lang.NullPointerException Message Cannot invoke method findAllById_of_projectAndParent_id() on null object

Answer 1

Try adding this at the begining of your gsp:

<%@ page import="package.Project_permission" %>
<%@ page import="package.Employee" %>

Replace package with the actual package.

Anyway if you are going to findById, its better to do a Employee.get(id)