Dubbed, J2ObjC, the Java to iOS Objective-C translator’s main aim is to enable developers to write non-UI code in Java and then through the translator make it compatible with iOS devices. “The goal is to write an application’s non-UI code (such as data access, or application logic) in Java, which can then be shared by Android apps, web apps (using GWT), and iOS” writes Tom Ball, Google Engineer on Google Open Source Blog.
Ball notes that J2ObjC is not a Java emulator. Using the translator, developers can converts Java classes to Objective-C classes that directly use the iOS Foundation Framework. Some of the features of the translator include full Java 6 language; support for most of the Java runtimes; JUnit test translation and execution; compatibility with build tools like Xcode and Make.
The J2ObjC project page includes details on how developers can use the tool, source code and current issues. If anyone is interested in knowing how the translator works, design documentation is also available.