API Analyzers are the extensions that make Revapi understand a new "language" or a new type of API.

It is responsible for providing archive analyzers which are able to transform incoming binary archives into trees of API elements and for supplying an initial difference analyzer that, based on some kind of rules, tells whether the matching element pairs are different and how.

In this example project we implement a "property files analyzer". This simple analyzer will be able to compare property files, detect added or removed keys and detect keys with changed values.

The first step for each API analyzer is to implement a class representing the API elements. The elements coming from a single API analyzer are supposed to all be mutually comparable which is crucial for the comparison algorithm employed by Revapi. Therefore, each API analyzer needs to have its own type of elements.

An archive analyzer is created by the API analyzer for a given API. It is responsible for turning the archives of the API into a tree of API elements.

The API analyzer then supplies a "difference analyzer". A gadget that Revapi uses to check whether two elements, one coming from the old API and the other from the new API are considered different or not. Revapi does a parallel depth-first traversal of the element trees (created by the archive analyzers) and can detect add, removed or changed elements. The job of the difference analyzer is to produce a report detailing the differences that quantify the change on the elements.