OMSjp is a uniform Java library for working with heterogenous OMS platforms. It provides a collection of interfaces that represent the concepts of the OMS database management system in the Java world. Users that want to build Java based applications can create an OMSjp driver and open arbitrary databases. Objects, collections and associations can be retrieved, queried and updated. OMSjp also supports the creation of new data and metadata, as well as the execution of queries.