Netscape Communications Corp’s plan to incorporate Visigenic Software Inc’s PostModern Computing Inc-derived object request broker in its Navigator browser and server software is still a year or so out at best, which means widespread deployment of end-to-end systems based upon the Object Management Group Corba object model with commercial browsers sitting at the front-end, are still some way off. Object-relational mapping and cacheing software house Persistence Software Inc believes most organizations doing real distributed object work are creating systems with intranet-based client applications in mind anyway. If commodity non-customized browsers become an option, then fine, but the world will likely have moved on considerably before that option arrives. Meantime, Persistence and others are engaged in putting longer pieces of distributed object piping together. As expected (CI No 2,905), Persistence has integrated its software with Dubliner Iona Technologies Ltd’s Orbix object request broker, saying it will enable multiple distributed clients to access objects stored in the Persistence live objects cache as C++ objects. Applications created by object brokers need to store objects in relational databases. Persistence maps database objects into what it calls a live object cache, minimizing queries and thereby speeding application performance.
Transaction application servers
The software creates what it calls transaction application or TransApp servers that concentrate application data and logic in a middle tier between client objects and databases. Multiple clients share a TransApp server, which maps object changes back to database transactions and optimizes performance by loading frequently-accessed information into a shared object cache. Clients can view the C++ objects in any language supported by the object broker, including Java, C++ and ActiveX. Persistence supports Iona’s version of the Corba persistent object service enabling Corba objects to be stored in a relational database, and the pair have also integrated their respective transaction managers. Persistence has tailored a version of its software ready to run with Iona out of the box. Until now, similar systems had to be hand-stitched. Campbell, California-based Halcyon Software Inc connected Persistence with PostModern-derived VisiBroker object broker. Long time Persistence partner SunSoft Inc connected the technology with its Neo object broker and had Persistence add support for multiple threads at the same time. That project, plus the persistent object specification Persistence has written for relational-to-object broker mapping and has offered up to the Object Management Group, provided the impetus for the Iona integration work. Persistence’s Iona-optimized software is out now as a special order item; the two firms share European distribution channels. Persistence is now up to release 3.3 of its software, which includes both the object builder mapping and object server cacheing mechanisms. It plans to extend the cacheing technology with a discrete line of TransApp server products. Version 3.4 of the software is due next month. It has an event manager notification system under way. It has also accelerated some of its other development work – support for ActiveX was demonstrated at Object World this week and will feature in a 3.5 release due by the year-end. Persi stence currently supports Windows NT, 95, C++ and Java clients. 4.0, due in the first half of 1997 will support Network OLE. A 4.2 release in the second half of 1997 will support Java servers and the cacheing of Java applets. Before that Persistence is preparing a Coffee Grinder Java mapping tool that will use Java DataBase Connectivity. The growth of Persistence’s three-tier application technology is not being pushed by key partner Sybase Inc, which markets the Persistence mapping software as OpenConnect middleware for users that want to connect object applications with Sybase SQL Server tables. After all, the database companies want customers to use their databases as the distributed mechanism. Privately-held Persistence is up to 50 st aff.
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