Sun is working with Motorola, Nokia, Siemens and Sony Ericsson on a certification program for mobile Java applications, designed to speed time to market and increase the reach of Java.
But Sun critics claim only making Java open source will guarantee its ubiquity and its power as a weapon against Microsoft, and this week IBM adopted the popular publicity tactic of the 'open letter', calling on Sun to open up the Java specifications.
Sun has not yet replied to the letter from Rod Smith, IBM's vice president of emerging technologies, but it is under increasing pressure to fully open up Java - mainly from companies like IBM and Nokia that have significant technical resources and strategic directions tied up in the software, and that see it as their primary method to fight off Microsoft .Net and Visual Studio.
The handset makers have been instrumental in various moves designed to accelerate uptake of Java. The latest, the 'Java Verified' program, is designed to enable Java mobile apps to run on phones from multiple vendors with only one certification required. Sun will manage and operate the scheme, which aims to maximise available software and allow developers and content providers to get their products to market more quickly.
Last year, the Java Community Process, the group responsible for maintaining Java and governing its semi-open source model, updated its methods to encourage wider, faster uptake. The changes were instigated by Nokia, Sun, Oracle and BEA, among the companies that have most to gain or lose in Java's war with Microsoft.
But even with these various changes, it remains difficult to get changes implemented through the JCP and the process has not encouraged the rapid accumulation of applications from small developers as languages like Psion OPL do through their open source models.
The concessions by Sun to open source and small developers are little better than lip service. It is still retaining a firm rein, refusing to accept any API issued under what it calls 'viral' licensing such as the Linux General Public License, and maintaining complete control over the Java language specification with its right of veto of any proposed change.
More critically, while some of its hesitant steps towards open source may have real value, it is not offering any real incentive to small developers to submit ideas to the Java process and this is something that is increasingly frustrating the mobile phone makers, which depend on these small software houses for their applications bases. Large companies dominate the JCP's agenda be-cause they have the considerable time required to put into the JSR process, and can afford the $5,000 per person annual fee for companies to join.
Many of the 3m Java developers in the world, especially in the mobile community, are individuals who feel excluded from the Java process, Only 531 of the world's 3m Java developers have been actively involved in a JSR, and predictably this number is dominated by the big names, with Nokia being the third most active in leading JSRs after Sun itself and IBM.
As Microsoft improves its own mobile development tools and the new release of .Net Compact Framework, the need to make Java simple, inclusive and open becomes more urgent.
"Sun's strong commitment to open-source Java would speed the development of a first-class and compatible open-source Java implementation to the benefit of our customers and our industry," Smith wrote to Rob Gingell, a Sun vice president. "We are firmly convinced the open source community would rally around this effort."
Open source advocate Eric Raymond also sent Sun a letter last week, saying that the company had to choose between control and ubiquity of Java.
While the debate rages, Sun and its main rival for providing mobile Java Virtual Machines, Esmertec, both upgraded their products. Sun released Java for Smartphone HotSpot Implementation and J2ME Web Services, an upgraded version of its mobile web services particularly focused on dual-mode smartphones. Sun claims the new implementation of J2ME runs six times faster than the current reference platform, and that the HotSpot Implementation cuts porting and deployment times and costs for handset makers or carriers.
Meanwhile, Esmertec, which focuses on very small footprint JVMs for mass market phones, announced Jcap CLDC, a component application platform for creating highly customised and branded J2ME apps. Customisation can be performed at build time or over the air and component-based techniques enable extensive reuse and cut time to market.
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