Oracle's acquisition of Sun Microsystems and Sun's Java programming language could "wreak havoc" on the enterprise software market, according to a report by AMR Research, because so many vendors make applications that rely on Java.

Of the top 50 software vendors ranked by AMR, two-thirds have applications that require Java, including many Oracle competitors.

Last month, Oracle said the U.S. Department of Justice was still looking at its acquisition of Sun with regard to how rights to Java are licensed. However, Oracle said, it still expects the deal to close this summer.

"Not only will vendors be impacted by the fragile economy, but 33 out of the top 50 vendors will have to reevaluate their commitment to the Java programming language," said AMR vice president Dennis Gaughan.

SAP, with nearly its $16 billion in revenue, and Oracle, with $8.6 billion in revenue, dominate the market for enterprise software, and they also affect how well different categories of the software perform.

Project Lifecycle Management, the one category where Oracle and SAP don't play, was the only category that shrank last year, according to AMR. It was down 2 percent. The rest -- ERP, supply chain management, human capital management and customer relationship management (CRM) -- grew between 4 percent and 9 percent.

But because of the weak economy, 2009 will be different, Gaughan said. AMR forecasts declines of between 2 percent and 6 percent for all enterprise software, depending on how tight corporate budgets are and how reluctant companies are to buy new licenses.

Opportunities will still occur in software sold as a service, which continues to grow because it's cheaper and faster to deploy, and any software that helps companies cope with the economy. This includes software for workforce management, regulatory compliance and procurement.

Small and medium businesses are also still buying software and causing tough competition among vendors, AMR said.

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