return "(" + queryWhere(left) + " OR " + queryWhere(right) + ")";
return '(' + queryWhere(left) + " OR " + queryWhere(right) + ')';
    private String queryWhere(WorkflowQuery query) {        if (query.getLeft() == null) {            // leaf node            return queryComparison(query);        } else {            int operator = query.getOperator();            WorkflowQuery left = query.getLeft();            WorkflowQuery right = query.getRight();            switch (operator) {            case WorkflowQuery.AND:                return "(" + queryWhere(left) + " AND " + queryWhere(right) + ")";            case WorkflowQuery.OR:                return "(" + queryWhere(left) + " OR " + queryWhere(right) + ")";            case WorkflowQuery.XOR:                return "(" + queryWhere(left) + " XOR " + queryWhere(right) + ")";            }        }        return ""; // not sure if we should throw an exception or how this should be handled    }