<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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                                        <img id="email-avatar" src="https://hibernate.onjira.com/secure/useravatar?avatarId=10162" alt="" height="48" width="48" border="0" align="left" style="padding:0;margin: 0 16px 16px 0;" />
                        <div id="email-action" style="padding: 0 0 8px 0;font-size:12px;line-height:18px;">
                                    <a class="user-hover" rel="matthewadams" id="email_matthewadams" href="https://hibernate.onjira.com/secure/ViewProfile.jspa?name=matthewadams" style="color:#6c797f;">Matthew Adams</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/BVAL-341'>BVAL-341</a>
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                        <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/BVAL-341'><strong>Add @Nullable for explicit communication of nullability</strong></a>
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</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%">
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                <td id="email-gutter" style="width:64px;white-space:nowrap;"></td>
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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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        <strong style="font-weight:normal;color:#505050;">Assignee:</strong>
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                    Unassigned            </td>
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        <strong style="font-weight:normal;color:#505050;">Components:</strong>
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                    api,                     spec-general,                     tck            </td>
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        <strong style="font-weight:normal;color:#505050;">Created:</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%;">
        04/Dec/12 1:09 PM
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        <strong style="font-weight:normal;color:#505050;">Description:</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%;">
        <p style='margin-top:0;margin-bottom:10px;'>JSR-303 released constraint annotations @NotNull and @Null, but not @Nullable.</p>

<p style='margin-top:0;margin-bottom:10px;'>@NotNull is no doubt useful, as the first thing someone asks when he sees a method or field of a non-primitive type is "Can that thing be null?"  @NotNull answers that question clearly.</p>

<p style='margin-top:0;margin-bottom:10px;'>@Null seems to be not very useful, but I understand its symmetry to @NotNull, so it makes sense.</p>

<p style='margin-top:0;margin-bottom:10px;'>What's missing, IMHO, is an annotation that *<b>explicitly</b>* declares that the annotated element can be null or non-null, which is why I'm proposing that @Nullable be added to JSR 303 (or its successor).  Without it, the developer that sees a nullable type will still ask "Can that thing be null?"  They may assume so, since it's not annotated with @NotNull, but it's not guaranteed.  In the world since JSR 303's release, one would expect to be able to clearly know whether something is explicitly allowed to be null, to be non-null, or to be either, without having to resort to RTFMing.</p>

<p style='margin-top:0;margin-bottom:10px;'>There would be no explicit validator implementation corresponding to @Nullable, as it would always return true (or the validator impl could be hardcoded to always return true, but that seems a waste).</p>

<p style='margin-top:0;margin-bottom:10px;'>I'm also asking that JSR 303 publish this annotation in the javax.validation.constraints package, so as not to be confused with JSR 305's @javax.annotation.Nullable annotation, which is used for static code analysis.</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;">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/BVAL">Bean Validation</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>
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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%;">
                    null
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        <strong style="font-weight:normal;color:#505050;">Priority:</strong>
    </td>
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                <img src="https://hibernate.onjira.com/images/icons/priority_major.gif" height="16" width="16" border="0" align="absmiddle" alt="Major">        Major
    </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;">Reporter:</strong>
    </td>
    <td style="color:#000000;font-family:Arial,FreeSans,Helvetica,sans-serif;font-size:12px;padding:0 0 10px 0;width:100%;">
                                        <a class="user-hover" rel="matthewadams" id="email_matthewadams" href="https://hibernate.onjira.com/secure/ViewProfile.jspa?name=matthewadams" style="color:#6c797f;">Matthew Adams</a>
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