if ( modsOid.equals( aliasAttributeOid ) )
if ( modsOid.equals( aliasAttributeOid ) && mods.size() > 0 )
    private void replace( BigInteger id, Attributes entry, Attribute mods ) throws NamingException    {        String modsOid = oidRegistry.getOid( mods.getID() );                if ( hasUserIndexOn( modsOid ) )        {            Index idx = getUserIndex( modsOid );            // Drop all existing attribute value index entries and add new ones            idx.drop( id );            idx.add( mods, id );            /*              * If no attribute values exist for this entryId in the index then             * we remove the existance index entry for the removed attribute.             */            if ( null == idx.reverseLookup( id ) )            {                existanceIdx.drop( modsOid, id );            }        }        String aliasAttributeOid = oidRegistry.getOid( Partition.ALIAS_ATTRIBUTE );        if ( modsOid.equals( aliasAttributeOid ) )        {            dropAliasIndices( id );        }        // Automatically replaces old attributes with new modified ones        entry.put( mods );        if ( modsOid.equals( aliasAttributeOid ) )        {            String ndnStr = ( String ) ndnIdx.reverseLookup( id );            addAliasIndices( id, new LdapDN( ndnStr ), ( String ) mods.get() );        }    }