e generation of a
  foreign key constraint when table generation is in effect. 
  If both this element and the <code>foreignKey</code> element 
  of any of the <code>PrimaryKeyJoinColumn</code> elements are specified, 
  the behavior is undefined.  If no foreign key annotation element
  is specified in either location, the persistence provider's
  default foreign key strategy will apply.</div>
<dl>
<dt><span class="simpleTagLabel">Since:</span></dt>
<dd>2.1</dd>
</dl>
<dl>
<dt>Default:</dt>
<dd>@jakarta.per