User Guide

ePADD User Guide v11

Technical Information

ePADD is written in Java and Javascript and powered by Apache Tomcat (v9) using Java EE Servlet API (v3.x) and Java Mail (v1.4.2). Text and metadata extraction, indexing and retrieval is performed by Apache Lucene (v4.7) and Apache Tika (v1.8). Charting and visualization is supported using the D3-based reusable chart library (v0.4.10). Oracle's Java Application Bundler and Launch4J are used for packaging on Mac and Windows platforms respectively. Other Java libraries from Apache (Lang, commons, CLI, IO, logging, etc.) are also used. JSON formatting is performed with the libraries org.json and Gson.


ePADD has implemented its own natural language processing (NLP) toolkit which is used for named entity extraction, disambiguation and other tasks. This toolkit supplants the Apache OpenNLP used in earlier beta versions of the ePADD software. We continue to use Muse as an internal library within ePADD. However, the Apache OpenNLP proved insufficient for our needs (at least for name recognition), and after various rounds of customization, we built our own named entity recognizer. This toolkit uses external datasets such as Wikipedia/DBpedia, Freebase, Geonames, OCLC FAST and LC Subject Headings/LC Name Authority File.


The project is developed with IDEs like IntelliJ Idea and Eclipse, built with Apache Maven, Ant, and custom shell scripts, and tracked using Git for source control and issue tracking. The ePADD software client is browser-based and compatible with Chrome and Firefox. It is optimized for Windows 7 SP1/11,  OSX 10.12/10.13, and Ubuntu 16.04 machines, using Java 11.