Using the Java Gateway in a Production - InterSystems Documentation

Proxy Call Sequence
Figure 1–3: Importing Java Classes
1. The Ensemble session sends an import request.
2. Upon receiving the request, the Java Gateway worker thread introspects the indicated Java packages and classes.
3. If it finds any Java classes that are new or changed, or that have no proxy classes on the Ensemble side, the thread
generates new proxy classes for them.
Important:
The Java Gateway import only imports classes, methods, and fields marked as public.
1.6 Proxy Call Sequence
A call to any Ensemble proxy method initiates the following sequence of events:
1. All Ensemble proxy parameters are marshaled onto the wire. This is a very simple process in the vast majority of cases
— parameters are simply written into the output TCP/IP buffer.
2. A message is sent over the TCP/IP connection to the Java Gateway worker thread. The message consists of the method
name, marshaled parameters and, in some instances, other minor load.
3. The Java Gateway worker thread consumes the message, unmarshals the parameters, finds the appropriate method or
constructor call, and invokes it using Java reflection. If the given method is an overloaded method, the gateway uses
a method overload algorithm to find the right Java method version. For details, see the Overloaded Methods section
of the “Mapping Specification” chapter of this guide.
4. The results of the method invocation (if any) are marshaled onto the wire and sent back to the Ensemble side over the
same TCP/IP channel.
Using the Java Gateway 7