You must have ant 1.7.0 or newer installed in your system.
You can download it from
here
.
Execute 'ant jar.jdk5', the distribution jar
should be inside the
target
directory.
Extras
You may additionally generate the source jars and jdk15
javadoc API pages using the provided
Ant
targets. Type 'ant -p' to get more info on those targets.
This site and the documentation for the jdk13 package is
still built with
Maven
.