Properties formatterArgs() throws IOException {
        Properties formatterArgs = options.has(messageFormatterConfigOpt)
                ? Utils.loadProps(options.valueOf(messageFormatterConfigOpt))
                : new Properties();
        String keyDeserializer = options.valueOf(keyDeserializerOpt);
        if (keyDeserializer != null && !keyDeserializer.isEmpty()) {
            formatterArgs.setProperty(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, keyDeserializer);
        }
        String valueDeserializer = options.valueOf(valueDeserializerOpt);
        if (valueDeserializer != null && !valueDeserializer.isEmpty()) {
            formatterArgs.setProperty(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, valueDeserializer);
        }
        formatterArgs.putAll(CommandLineUtils.parseKeyValueArgs(options.valuesOf(messageFormatterArgOpt)));

        return formatterArgs;
    }
Used to retrieve the correct value for the consumer parameter 'auto.offset.reset'.
Order of priority is:
  1. Explicitly set parameter via --consumer.property command line parameter
  2. Explicit --from-beginning given -> 'earliest'
  3. Default value of 'latest'
In case both --from-beginning and an explicit value are specified an error is thrown if these
are conflicting.
tools/src/main/java/org/apache/kafka/tools/consumer/ConsoleConsumerOptions.java