> Jasmin was written because, at the time that we wrote the Java Virtual Machine book for O'Reilly, Sun had not published an assembler format for the Java virtual machine.
> Generating a binary Java .class file is pretty fiddly. Its like creating an a.out (or .exe) file by hand. Even using a Java package like JAS (a Java API for creating class files, used internally by Jasmin and written by KB Sriram), you need to know a lot about the philosophy of the Java Virtual Machine before you can write something at the Virtual Machine level and generate a Java class.
> We wanted something that made it very easy for a student or programmer to explore the Java Virtual Machine, or write a new language which targets the VM, without getting into the details of constant pool indices, attribute tables, and so on.