presto-parser/src/main/java/io/prestosql/sql/parser/StatementSplitter.java/StatementSplitter/isEmptyStatement
class StatementSplitter:    public static boolean isEmptyStatement(String sql)
    {
        TokenSource tokens = getLexer(sql, ImmutableSet.of());
        while (true) {
            Token token = tokens.nextToken();
            if (token.getType() == Token.EOF) {
                return true;
            }
            if (token.getChannel() != Token.HIDDEN_CHANNEL) {
                return false;
            }
        }
    }