Introducing Sawmill, an open-source Java library for enriching, transforming and filtering JSON documents. If you're into centralized logging, you are probably familiar with the ELK Stack: Elasticsearch, Logstash and Kibana. Just in case you're not, ELK (or Elastic Stack, as it's being renamed these days) is a package of three open-source components, each responsible for a different task or stage in a data pipeline.

In my last few articles, I've looked at several ways one can apply machine learning, both supervised and unsupervised. This time, I want to bring your attention to a surprisingly simple—but powerful and widespread—use of machine learning, namely document classification.