Sun Microsystems and IBM Corp both revealed technology designed to simplify the development and deployment of distributed applications in Java at the JavaOne conference in San Francisco this week. Sun’s JavaSpaces has reached its first beta version, while IBM’s TSpaces is still a research project posted on the IBM AlphaWorks Web site. Both projects cited the Yale University Linda programming language written by David Gelernter, designed for parallel processing on networks of computers, as their main influence. Linda, JavaSpaces and T Spaces all use the concept of tuples, collections of data items referenced by name, which are place in and retrieved from a temporary shared memory space. Sun’s JavaSpaces is intended to provide a simple and lightweight infrastructure for networked applications, so that mainstream Java programmers can build distributed applications with little training. It uses Java’s strong typing systems to find, match and reference objects by type or value. JavaSpaces, which works in conjunction with Sun’s RMI Remote Method Invocation software, is an interface and behavior specification, but Sun has done its own implementation, using Object Design Inc’s ObjectStore PSE as the object repository for the system. It expects other implementations from both inside and outside of Sun to emerge over time. The ObjectStore database, written in Java and certified 100% Java, is used to store Java objects, which can be retrieved, updated and searched by different distributed Java components. JavaSpaces doesn’t try to provide the functions of a full scale relational or object database, but just provides simple matching for distributed protocols. It’s a loosely coupled approach that scales well, and cuts out the server-side programming that would be required with traditional remote procedure call implementations, claims Sun. JavaSpaces is expected to be used for the middle tier of such Java-built applications and services as workflow systems, customer management, supply chain management, trading and auction systems, and publish and subscribe systems. The Beta version is due out in the second quarter of the year, with the final version available free on the Web by the third quarter. Meanwhile IBM’s TSpaces, developed at IBM’s Almaden Research Center in San Jose, is described as a set of network communication buffers, APIs and classes that allows heterogeneous, Java-enabled devices to exchange data with little programming effort. It comes as a small footprint package including server software to implement the buffers and client software to access the buffers. It also provides group communication services, database services, URL- based file transfer and event notification services, and IBM says it can be used with palm devices, which can then participate on the network. There’s no guide to availability of Tspaces, which was posted on the AlphaWorks site last week to garner comments from anyone interested. Both companies said the two systems were very similar. The Linda language was first developed at Yale in the early and mid 1980s.
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