Jasmin is a Java Assembler Interface. It takes ASCII descriptions for Java
classes, written in a simple assembler-like syntax, using the Java
Virtual Machine instruction set. It converts them into binary Java class
files suitable for loading into a Java interpreter.

Jasmin was originally written as the companion to the
book "Java Virtual Machine", published by O'Reilly, written by
Jon Meyer and Troy Downing. (See http://www.ora.com/catalog/javavm/).
The book is now out of print. However, the Jasmin assembler retains its
usefulness as a utility, and continues its life as an OpenSource project.