The AIR abbreviation stands for Abstract Intermediate Representation, which is an abstract semantic graph (ASG) representing C++ source code as described in the D2.1: REPARA C++ Open Specification document. An ASG is based on an abstract syntax tree (AST), but it is extended by different kinds of edges, like method calls or references to identifiers or types.
The AIR access library is an API (Application Programming Interface) implemented in the
Java programming language, which allows easy access to the nodes of the AIR. It contains the classes representing the types of the AIR nodes (detailed in the following sections) that, in turn, can have different attributes and edges that point to other nodes. It also contains a built-in graph traversal algorithm and visitor mechanism that makes performing these operations easier.
AIR API Documentation: ICT-609666-D4.2-AIR-DOC
AIR Library: ICT-609666-D4.2-AIR-API