Speaking in Tokyo this week, Sun Microsystems Inc chief scientist John Gage said Jini – the Java Intelligent Network Infrastructure – will allow any device to plug into the network, simply by announcing it is available through a discovery protocol, a 25Kb piece of code built into it. The term Jini was apparently coined by Sun co-founder Bill Joy who generated a list of four-letter words staring with J. They picked the name to fit the acronym. Sun describes Jini as sitting atop Java virtual machines performing lookup, discovery and join activities. It includes Jini events that allow objects in different JVMs to identify state changes that may be of interest to other objects and send notification. Jini leasing allows objects to establish leases for sharing the computation resources of their platform with other objects. It offers fault-tolerance and a mechanism for distributed programming. Jini transaction provides two-phase commit protocol for Java objects in distributed systems. It is not dependent on the use of a database. JavaSpaces, which provides distributed storage, and is intended for use as a model for designing distributed systems, utilizes Jini. Jini specifications carry the same license as Java meaning developers can create their own ‘clean-room’ Jini implementations under the same restrictions as Java – implementing all APIs with no subsetting or supersetting. Jini uses the Java-to-Java remote method invocation protocol.
