a simple project prints "hello, world" using various build tools.
Builds ant, maven, and gradle in a row.
$ sh ./buildall.sh
...
Cleans all build outputs.
$ sh ./cleanall.sh
...
$
$ ant
...
$ java -jar dst/hello-world.jar
hello, world
$
$ mvn clean package
$ java -jar target/hello-world-noversion.jar
hello, world
$
$ gradle build
...
$ java -jar build/lib/hello-world.jar
hello, world
$
$ lein jar
...
$ java -jar target/hello-world-noversion.jar
hello, world
$