The Java RFC client packages are thread safe in the following sense:

• The global FactoryManager object is synchronized, meaning that multiple threads can concurrently invoke FactoryManager methods.
• The SessionManager object is synchronized.
• The MiddlewareInfo, UserInfo, ConnectInfo and the IRfcConnection’s implementation classes support multi-threaded subscriptions to their property change events.
• The IRfcConnection’s implementation class support multi-threaded subscriptions to its connection events.
• No class in the Java RFC implementation package has static variables. This means that multi-threaded accesses to any of the classes through the exposed interfaces are safe.

Note that the Java RFC server is also thread safe.

It is the your responsibility, however, to create and handle threads in your application program, and to synchronize individual objects if there are potentially multiple threads accessing them concurrently.

For example, if your application contains an IRfcModule object, and there are multiple threads that can add or set parameter values and invoke RFC calls through it, then this object along with its parameter objects need to be synchronized by your application. Only one function call is allowed to occur in a specific connection at any given time.