Chapter 1. Introduction

This guide is for engineers, consultants, and others who want to create custom XML-based rules for Windup.

If you are new to Windup, it is recommended that you start with the Windup User Guide. It provides detailed information about system requirements and detailed instructions on how to install and execute Windup. It also contains tips to optimize performance and provides links to other sources of information about Windup.

If you would like to contribute to the Windup source code base or provide Java-based rule add-ons, see the Windup Core Development Guide.

Windup is a rule-based migration tool that analyzes the APIs, technologies, and architectures used by the applications you plan to migrate. In fact, the Windup analysis process is implemented using Windup rules. Windup uses rules internally to extract files from archives, decompile files, scan and classify file types, analyze XML and other file content, analyze the application code, and build the reports.

Windup builds a data model based on the rule execution results and stores component data and relationships in a graph database, which can then be queried and updated as needed by the migration rules and for reporting purposes.

Windup rules use the following rule pattern:

when(condition)
  perform(action)
otherwise(action)

when(condition)
  perform(action)
otherwise(action)

Windup provides a comprehensive set of standard migration rules out-of-the-box. Because applications may contain custom libraries or components, Windup allows you to write your own rules to identify use of components or software that may not be covered by the existing ruleset.