code: public void unregisterPropertyExclusion( Class target, String propertyName ) {
        if( target != null && propertyName != null ) {
           Set set = (Set) exclusionMap.get( target );
           if( set == null ) {
              set = new HashSet();
              exclusionMap.put( target, set );
           }
           set.remove( propertyName );
        }
     }
docs: Removes a property exclusion assigned to the target class.<br>
  [Java -&gt; JSON]
  
  @param target a class used for searching property exclusions.
  @param propertyName the name of the property to be removed from the exclusion list.