Developed through the Java Community Process (JCP), the RMI Optional Package (RMI OP) brings the world of distributed applications to consumer and embedded devices.
Long a feature of the Java 2 Platform, Standard Edition (J2SE), remote method invocation enables applications written in the Java programming language to interoperate with each other in a transparent, flexible way, even when deployed on very different systems. With the advent of RMI OP, "very different systems" now includes, not only desktop and server systems, but small handheld and embedded devices. RMI OP is a subset of J2SE RMI that can be used on devices that support the Connected Device Configuration (CDC) of the Java 2 Platform, Mobile Edition (J2ME).
RMI OP supports the crucial features of the J2SE RMI package:
- Full RMI call semantics
- Marshalled object support
- RMI wire protocol
- Export of remote objects
- Client- and server-side distributed garbage collection
- The Activator interface and the client-side activation protocol
- Registry interfaces and export of a Registry remote object
Some features of J2SE RMI are not supported by RMI OP:
- RMI through firewalls by way of HTTP proxies
- RMI's multiplexing protocol
- Implementation model for an Activatable remote object
- Deprecated methods, classes, and interfaces
- Stub and skeleton compiler
- Support for the JDK 1.1 stub/skeleton protocol
Differences from J2SE RMI are described fully in the RMI OP specification.
The RMI OP reference implementation is based entirely on Java technology and does not require any porting effort. It can be deployed with CDC-based profiles like Foundation Profile, Personal Basis Profile, and Personal Profile. The release notes for the reference implementation include instructions for compiling applications that use RMI OP.
