News

XobotOS Replaces Java With C#

• By Keith Ward
• May 11, 2012

A new project from Xamarin has replaced the Java code underpinning the Android OS with C# code, allowing Microsoft-focused developers to write in that familiar language and build apps that should be faster than similar apps coded in Java.

Xamarin has gained fame with Mono, an open-source framework allowing Android and iOS apps to be built using C# running on top of Java. Now, with what the company calls the XobotOS Research Project, the Java layer has been removed via a "machine translation of Android from Java to C#," according to a blog post from Xamarin CTO Miguel de Icaza.

Building XobotOS involved converting more than a million lines of Java code into C#, de Icaza wrote. A tool called Sharpen was used to help in the translation, and the project resulted in an improved version of Sharpen, de Icaza says. Most of Androids layouts and controls, de Icaza says, have been converted, and to demonstrate, the post includes a Java-free screenshot of XobotOS running on a Linux desktop.

In terms of speed improvements, the blog includes a bar chart of a benchmark from a simple binary tree implementation in Java and C#. The chart shows a huge increase in performance between the two languages.

Xamarin has made XobotOS available on github. de Icaza says that XobotOS won't be "a focus" going forward, as the company wants to put its efforts toward its core products, Mono for Android and MonoTouch.

One other possible benefit of using XobotOS for Android development is that it would eliminate the kind of potential legal entanglements that Google finds itself in with Oracle, the patent-holder for Java. Replacing Java with C# would, of course, inoculate developers from the clutches of Oracle's lawyers.