Open Source Parser Generators in Java

parboiled is a pure Java library that provides a lightweight and easy-to-use, yet powerful and elegant PEG (Parsing Expression Grammar) parsing facility. You define your grammar rules directly in Java source, there is no need to write and maintain special, external grammar files. parboiled provides for clean separation of grammar and action code while preserving seamless integration with full IDE support (syntax hightlighting, code navigation, refactoring, etc.). parboiled minimizes the time and cost required for developing custom DSLs (Domain Specific Languages) in Java.