<style>
/* Changing the layout to use less space for mobiles */
@media screen and (max-device-width: 480px), screen and (-webkit-min-device-pixel-ratio: 2) {
    #email-body { min-width: 30em !important; }
    #email-page { padding: 8px !important; }
    #email-banner { padding: 8px 8px 0 8px !important; }
    #email-avatar { margin: 1px 8px 8px 0 !important; padding: 0 !important; }
    #email-fields { padding: 0 8px 8px 8px !important; }
    #email-gutter { width: 0 !important; }
}
</style>
<div id="email-body">
<table id="email-wrap" align="center" border="0" cellpadding="0" cellspacing="0" style="background-color:#f0f0f0;color:#000000;width:100%;">
    <tr valign="top">
        <td id="email-page" style="padding:16px !important;">
            <table align="center" border="0" cellpadding="0" cellspacing="0" style="background-color:#ffffff;border:1px solid #bbbbbb;color:#000000;width:100%;">
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                    <td bgcolor="#3e4c4e" style="background-color:#3e4c4e;color:#ffffff;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;line-height:1;"><img src="https://www.jboss.org/dms/hibernate/images/jira/jiraheader_hibernate.png" alt="" style="vertical-align:top;" /></td>
                </tr><tr valign="top">
    <td id="email-banner" style="padding:32px 32px 0 32px;">
        
                
        
        
            <table align="left" border="0" cellpadding="0" cellspacing="0" width="100%" style="width:100%;">
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                        <div id="email-action" style="padding: 0 0 8px 0;font-size:12px;line-height:18px;">
                                    <a class="user-hover" rel="hendimarcos" id="email_hendimarcos" href="https://hibernate.onjira.com/secure/ViewProfile.jspa?name=hendimarcos" style="color:#6c797f;">HĂȘndi Marcos</a>
     created <img src="https://hibernate.onjira.com/images/icons/improvement.gif" height="16" width="16" border="0" align="absmiddle" alt="Improvement"> <a style='color:#6c797f;text-decoration:none;' href='https://hibernate.onjira.com/browse/HHH-7892'>HHH-7892</a>
            </div>
                        <div id="email-summary" style="font-size:16px;line-height:20px;padding:2px 0 16px 0;">
                <a style='color:#6c797f;text-decoration:none;' href='https://hibernate.onjira.com/browse/HHH-7892'><strong>Illegal attempt to dereference path source [null]</strong></a>
            </div>
                    </td>
    </tr>
</table>
    </td>
</tr>
<tr valign="top">
    <td id="email-fields" style="padding:0 32px 32px 32px;">
        <table border="0" cellpadding="0" cellspacing="0" style="padding:0;text-align:left;width:100%;" width="100%">
            <tr valign="top">
                <td id="email-gutter" style="width:64px;white-space:nowrap;"></td>
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                    <table border="0" cellpadding="0" cellspacing="0" width="100%">
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        <strong style="font-weight:normal;color:#505050;">Issue Type:</strong>
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                <img src="https://hibernate.onjira.com/images/icons/improvement.gif" height="16" width="16" border="0" align="absmiddle" alt="Improvement">        Improvement
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</tr>                        <tr valign="top">
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 10px 10px 0;white-space:nowrap;">
        <strong style="font-weight:normal;color:#505050;">Affects Versions:</strong>
    </td>
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
                    4.1.9            </td>
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        <strong style="font-weight:normal;color:#505050;">Assignee:</strong>
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    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
                    Unassigned            </td>
</tr>                                                <tr valign="top">
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 10px 10px 0;white-space:nowrap;">
        <strong style="font-weight:normal;color:#505050;">Components:</strong>
    </td>
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
                    entity-manager,                     query-criteria            </td>
</tr>
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        <strong style="font-weight:normal;color:#505050;">Created:</strong>
    </td>
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
        26/Dec/12 8:05 PM
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    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 10px 10px 0;white-space:nowrap;">
        <strong style="font-weight:normal;color:#505050;">Description:</strong>
    </td>
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
        <p style='margin-top:0;margin-bottom:10px;'>ERROR - java.lang.IllegalArgumentException: Illegal attempt to dereference path source <span class="error">&#91;null&#93;</span><br/>
Using: Criteria JPA 2 with hibernate</p>

<p style='margin-top:0;margin-bottom:10px;'>Stacktrace: <br/>
java.lang.IllegalArgumentException: Illegal attempt to dereference path source <span class="error">&#91;null&#93;</span><br/>
at org.hibernate.ejb.criteria.path.AbstractPathImpl.illegalDereference(AbstractPathImpl.java:104)<br/>
at org.hibernate.ejb.criteria.path.AbstractPathImpl.get(AbstractPathImpl.java:186)</p>

<p style='margin-top:0;margin-bottom:10px;'>Cause:<br/>
I was doing a get on a PluralAttributePath<br/>
Attribute type java.util.List</p>

<p style='margin-top:0;margin-bottom:10px;'>initial code:<br/>
Root root = criteriaQuery.from(Order.class); <br/>
Path path = root.get(key); //path to OrderLines (java.util.List)<br/>
path = path.get("description"); //throws exception since Ordelines was a many to many join OR one to many</p>

<p style='margin-top:0;margin-bottom:10px;'>new code:<br/>
Root root = criteriaQuery.from(Order.class);<br/>
Join join = criteriaQuery.join("orderLines"); (java.util.List)<br/>
Path path = root.get(key); //path to OrderLines<br/>
path = join.get("description");</p>

<p style='margin-top:0;margin-bottom:10px;'>========</p>

<p style='margin-top:0;margin-bottom:10px;'>In others providers the join is implicit<br/>
As the queries using criteria are already very verbose, I think it would be a facility.</p>
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    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 10px 10px 0;white-space:nowrap;">
        <strong style="font-weight:normal;color:#505050;">Environment:</strong>
    </td>
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
        java oracle 7
<br/>

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    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 10px 10px 0;white-space:nowrap;">
        <strong style="font-weight:normal;color:#505050;">Project:</strong>
    </td>
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
        <a style="color:#6c797f;" href="https://hibernate.onjira.com/browse/HHH">Hibernate ORM</a>
    </td>
</tr>                        <tr valign="top">
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 10px 10px 0;white-space:nowrap;">
        <strong style="font-weight:normal;color:#505050;">Labels:</strong>
    </td>
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
                    hibernate
                    jpa2
                    criteria
            </td>
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    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 10px 10px 0;white-space:nowrap;">
        <strong style="font-weight:normal;color:#505050;">Priority:</strong>
    </td>
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
                <img src="https://hibernate.onjira.com/images/icons/priority_major.gif" height="16" width="16" border="0" align="absmiddle" alt="Major">        Major
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        <strong style="font-weight:normal;color:#505050;">Reporter:</strong>
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                                        <a class="user-hover" rel="hendimarcos" id="email_hendimarcos" href="https://hibernate.onjira.com/secure/ViewProfile.jspa?name=hendimarcos" style="color:#6c797f;">HĂȘndi Marcos</a>
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