SableCC explained

SableCC
Latest Release Version:	3.7
Latest Preview Version:	4-beta.4^[1]
Programming Language:	Java
Platform:	Java Virtual Machine
Genre:	Parser/scanner generator
License:	GNU Lesser General Public License
Website:	http://www.sablecc.org/

SableCC is an open-source compiler generator (or interpreter generator) in Java. Stable version is licensed under the GNU Lesser General Public License (LGPL). Rewritten version 4 is licensed under Apache License 2.0.

SableCC includes the following features:

Deterministic finite automaton (DFA)-based lexers with full Unicode support and lexical states.
Extended Backus–Naur form grammar syntax. (Supports the *, ? and + operators).
LALR(1) based parsers.
Automatic generation of strictly-typed abstract syntax trees.
Automatic generation of tree-walker classes.

References