A jar is a packaging mechanism. It is not required step in most builds that I've encountered. Nor is it required to run (test) the code. Java classes can al

A jar is a packaging mechanism. It is not required step in most builds that I've encountered. Nor is it required to run (test) the code. Java classes can also be linked into a CLASSPATH from an unpackaged directory. Infrequent packaging does not imply infrequent building and/or testing.