Connection getConnection(String conn) throws Exception {
    if (conn == null || conn.equalsIgnoreCase("default")) {
      conn = exec.conf.defaultConnection;
    }
    return exec.conn.getConnection(conn);
  }
Get the connection (open the new connection if not available)
@throws Exception
hplsql/src/main/java/org/apache/hive/hplsql/Exec.java