Class TimeoutMarshaller

core/src/main/java/io/grpc/internal/GrpcUtil.java:656–705

Marshals a nanoseconds representation of the timeout to and from a string representation, consisting of an ASCII decimal representation of a number with at most 8 digits, followed by a unit. Available units: n = nanoseconds u = microseconds m = milliseconds S = seconds M = minutes H = hours The

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  @VisibleForTesting
  static class TimeoutMarshaller implements Metadata.AsciiMarshaller<Long> {

    @Override
    public String toAsciiString(Long timeoutNanosObject) {
      long cutoff = 100000000;
      // Timeout checking is inherently racy. RPCs with timeouts in the past ideally don't even get
      // here, but if the timeout is expired assume that happened recently and adjust it to the
      // smallest allowed timeout
      long timeoutNanos = Math.max(1, timeoutNanosObject);
      TimeUnit unit = TimeUnit.NANOSECONDS;
      if (timeoutNanos < cutoff) {
        return timeoutNanos + "n";
      } else if (timeoutNanos < cutoff * 1000L) {
        return unit.toMicros(timeoutNanos) + "u";
      } else if (timeoutNanos < cutoff * 1000L * 1000L) {
        return unit.toMillis(timeoutNanos) + "m";
      } else if (timeoutNanos < cutoff * 1000L * 1000L * 1000L) {
        return unit.toSeconds(timeoutNanos) + "S";
      } else if (timeoutNanos < cutoff * 1000L * 1000L * 1000L * 60L) {
        return unit.toMinutes(timeoutNanos) + "M";
      } else {
        return unit.toHours(timeoutNanos) + "H";
      }
    }

    @Override
    public Long parseAsciiString(String serialized) {
      checkArgument(serialized.length() > 0, "empty timeout");
      checkArgument(serialized.length() <= 9, "bad timeout format");
      long value = Long.parseLong(serialized.substring(0, serialized.length() - 1));
      char unit = serialized.charAt(serialized.length() - 1);
      switch (unit) {
        case 'n':
          return value;
        case 'u':
          return TimeUnit.MICROSECONDS.toNanos(value);
        case 'm':
          return TimeUnit.MILLISECONDS.toNanos(value);
        case 'S':
          return TimeUnit.SECONDS.toNanos(value);
        case 'M':
          return TimeUnit.MINUTES.toNanos(value);
        case 'H':
          return TimeUnit.HOURS.toNanos(value);
        default:
          throw new IllegalArgumentException(String.format("Invalid timeout unit: %s", unit));
      }
    }
  }

  /**
   * Returns a transport out of a PickResult, or {@code null} if the result is "buffer".