PNUTS

Pnuts is a dynamic scripting language for the Java Platform. It is designed to be used in a dual language system with the Java programming language. The goals of the Pnuts project are to provide a small, fast scripting language that has tight integration with the Java language. Pnuts uses syntax that is simple and friendly to Java developers, while also being very expressive.

Relationship to Java
Because Java and Pnuts share the same type system, Java code can easily invoke or define Pnuts functions. Likewise, Pnuts code can easily manipulate Java objects. Pnuts code can even define Java classes. Because Pnuts compiles to Java byte codes, these classes can be used by Java just like any other class. A class written in Pnuts can even later be replaced by a class written in Java with no other code changes.

History
Pnuts was originally developed in 1997 by Toyokazu Tomatsu as a testing tool for Java classes. Pnuts has since been extended, mainly focusing on essential functionality required for a Java-based scripting engine, such as a module system and bytecode compiler.