Incorrect result of isNullable for constant values

[mwisnicki]

isNullable for SELECT 1 returns 1 (columnNullable) instead of 0 (columnNoNulls) or 2 (columnNullableUnknown).

//DEPS com.amazon.redshift:redshift-jdbc42:2.1.0.34

import java.sql.*;

public class RedshiftDemo {
    private static final String DB_URL = System.getenv("REDSHIFT_URL");
    private static final String DB_USER = System.getenv("REDSHIFT_USER");
    private static final String DB_PASSWORD = System.getenv("REDSHIFT_PASSWORD");

    public static void main(String[] args) throws Exception {
        try (Connection conn = DriverManager.getConnection(DB_URL, DB_USER, DB_PASSWORD);
             Statement stmt = conn.createStatement();
             ResultSet rs = stmt.executeQuery("SELECT 1, 'hi'")) {

            System.out.println("Nullable[1]:" + rs.getMetaData().isNullable(1));
            System.out.println("Nullable[2]:" + rs.getMetaData().isNullable(2));
            rs.next();
            System.out.printf("Query result: %s %s%n", rs.getInt(1), rs.getObject(2));
        }
    }
}

Nullable[1]:1
Nullable[2]:1
Query result: 1 hi