jtopen is an open source version of the IBM Toolbox for Java (jt400) for using IBM i (previously iSeries and AS/400) system resources.
The jtopen
software is an open source version (IBM Public License) of IBM's licensed software IBM Toolbox for Java
. It is produced by the same team that produces the licensed software and generally gets updates and new features before the licensed software (PTF's).
More information can be found on the project's Sourceforge page.