OCSelot is a lightweight Java middleware that allows plain old Java objects for services, requires no ORB, IDL, or XML configuration, allows remote and local modes, has distributed garbage collection, provides for security, and is most easy to use
Use MsgConnect to exchange information between parts of your application that work on the same or on different computers. MsgConnect is a cross-platform message-oriented middleware that can be used in both client-server and peer-to-peer modes.
The UnityJDBC driver can integrate and query any number of JDBC-accessible data sources (including Oracle, SQL Server, MySQL, and Postgres) in a single SQL query. The query can join or match data between sources and return a single ResultSet.