presto-parser/src/main/java/io/prestosql/sql/tree/DefaultTraversalVisitor.java/DefaultTraversalVisitor/visitJoin
class DefaultTraversalVisitor:    @Override
    protected R visitJoin(Join node, C context)
    {
        process(node.getLeft(), context);
        process(node.getRight(), context);

        node.getCriteria()
                .filter(criteria -> criteria instanceof JoinOn)
                .map(criteria -> process(((JoinOn) criteria).getExpression(), context));

        return null;
    }