code: public static void debug(JShell state, PrintStream err, int flags, String format, Object... args) {
          if (isDebugEnabled(state, flags)) {
              err.printf(format, args);
          }
      }
docs: Displays debug info if the specified debug flags are enabled.
  
  @param state the current JShell instance
  @param err the {@code PrintStream} to report on
  @param flags {@code DBG_*} flag bits to check
  @param format format string for the output
  @param args args for the format string