I'm trying to use the SecurityPolicy class override the transform () method, but I need to run my query only for a Document of type (X). Is there another way to solve this?

public static class NoFileTransformer implements SQLQuery.Transformer {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    /** {@code ecm:primaryType <> 'File'} */
    public static final Predicate NO_FILE = new Predicate(
            new Reference(NXQL.ECM_PRIMARYTYPE), Operator.NOTEQ, new StringLiteral("TaskDoc"));

    @Override
    public SQLQuery transform(Principal principal, SQLQuery query) {
        WhereClause where = query.where;
        Predicate predicate;
        if (where == null || where.predicate == null) {
            predicate = NO_FILE;
        } else {
            // adds an AND ecm:primaryType <> 'File' to the WHERE clause
            predicate = new Predicate(NO_FILE, Operator.AND, where.predicate);
        }
        // return query with updated WHERE clause
        return new SQLQuery(query.select, query.from, new WhereClause(predicate),
                query.groupBy, query.having, query.orderBy, query.limit, query.offset);
    }
}