Codename One is an open-source cross-platform framework aiming to provide write once, run anywhere code for various mobile and desktop operating systems (like Android, iOS, Windows, MacOS, and others). It was created by the co-founders of the Lightweight User Interface Toolkit (LWUIT) project, Chen Fishbein and Shai Almog, and was first announced on January 13, 2012.
Codename One built upon the LWUIT platform abstraction by adding a simulator and a set of cloud-based build servers that build native applications from the Java bytecode.