alcheMo for iPhone
Notwithstanding Apple's position, at least one company has developed a translation program to take a Java program and convert it into a program for use on the iPhone.
This New Zealand company makes a translation program that will take a J2ME program and convert it into an iPhone app. The translation program uses a subset of Java ME CLDC 1.1 (Connected Limited Device Configuration) and MIDP 2.0.
Java developers may know what those two subsets are, but for others, they may ask “What is CLDC?" Basically, it defines a set of programming interfaces and virtual machines for mobile phone devices. These are important as space savers, because typically, the mobile devices are limited in resources. This helps support them.
MIDP or Mobile Information Device Profile is a programming specification for the use of Java on mobile phones. Both Java ME and MICP support JSR extension APIs. Furthermore, alcheMo for iPhone offers an Objective-C/Java bridge, which enables developers to take advantage of native iPhone APIs including Cocoa.
Cocoa is written in the Objective-C language. It consists of extensions to ANSI C. Objective-C is a more concise language than C++, and avoids the problems that C++ had. It has a syntax for defining classes, categories, protocols and message passing between objects.
See: Free Java iPhone Games