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POem.createQuery keeps returning null
 

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  1. POem.createQuery keeps returning null
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    <p>I have this application which i use JSF 2.0 and EclipseLink, i have entities created for a database made in MySQL, Created these entities using netbeans 7.1.2, it gets created automaticly.</p> <p>Then i use session beans to work with these entities, the thing is the <code>em.createQuery</code> always returns a null, though I checked NamedQueries in the entities and they perfectly match</p> <p>a sample from the entities named queries:-</p> <pre><code>@NamedQueries({ @NamedQuery(name = "Users.findAll", query = "SELECT u FROM Users u"), @NamedQuery(name = "Users.findByUserId", query = "SELECT u FROM Users u WHERE u.userId = :userId"), @NamedQuery(name = "Users.findByUsername", query = "SELECT u FROM Users u WHERE u.username = :username"), @NamedQuery(name = "Users.findByEmail", query = "SELECT u FROM Users u WHERE u.email = :email"), </code></pre> <p>notice how i use this findByEmail query in the session bean :-</p> <pre><code>public Users findByEmail(String email){ em.getTransaction().begin(); String find = "Users.findByEmail"; Query query = em.createNamedQuery(find); query.setParameter("email", email); Users user = (Users) query.getSingleResult(); </code></pre> <p>but it always returns null from this em.createNamedQuery, i tried using .createQuery first but it also was no good.</p> <p>the stacktrace of the exception</p> <pre><code>Caused by: java.lang.NullPointerException at com.readme.entities.sessionBeans.UsersFacade.findByEmail(UsersFacade.java:48) at com.readme.user.signup.SignupBean.checkAvailability(SignupBean.java:137) at com.readme.user.signup.SignupBean.save(SignupBean.java:146) 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:601) </code></pre> <p>What Seems To Be The Problem Here ?</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USLuiggi Mendoza
    1. USengma
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    1. PL
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      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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      1. PTAnswer
    1. VO
      singulars
      1. POem.createQuery keeps returning null
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POem.createQuery keeps returning null
      1. This table or related slice is empty.
      1. VTUpMod
    1. COThis problem is not related with JSF.
      singulars
      1. POem.createQuery keeps returning null
      1. USLuiggi Mendoza
    2. COHow are you obtaining the `EntityManager`?
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      1. POem.createQuery keeps returning null
      1. USPiotr Nowicki
    3. COI used @PersistenceContext annotation to get the em
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      1. POem.createQuery keeps returning null
      1. USengma
 

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