Java is an object oriented language which places emphasis on code
reuse. It is typical to reuse code previously developed and make it
available within current project. Even Standard edition consists of
about 3000 classes providing basic functionality and practices.
Managing this Zoo as individual classes would be cumbersome.
You can reuse the classes previously developed either by:
- listing directories which contain classes in
- incorporating classes in the jar file, and
adding jar to
file stands for
chive. The utility
to process these files is called jar
. It uses similar
syntax as popular UNIX tar
utility. Format of the
is that of zip
file, and these files can be created/unpacked
also with the popular zip/unzip
jar xvf some.jar
do the same thing: unpack the archive.