The Java Parser Generator
Java Compiler Compiler™ (JavaCC™) is the most popular parser generator for use with Java™ applications. A parser generator is a tool that reads a grammar specification and converts it to a Java program that can recognize matches to the grammar. In addition to the parser generator itself, JavaCC provides other standard capabilities related to parser generation such as tree building (via a tool called JJTree included with JavaCC), actions, debugging, etc.

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🛈 Helpful Resources
Installation & Getting Started
This page contains a bunch of tips that should aid you through the installation process.
The complete documentation for JavaCC.
Lexer Writing Tips
Tips for writing good JavaCC lexical analyzer specs. This can also help you if you are getting 'code size too big' error message from javac when you compile the generated token manager.
Grammar Repository
A repository of JavaCC grammars is being maintained on the JavaCC home page. We urge you to contribute your grammars to this repository or to the JavaCC authors for the benefit of others.
Source Code
The complete source code for JavaCC on GitHub.
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