Java provide a system for developing application software and deploying it in a cross-platform computing environment. Java is used in a wide variety of computing platforms from embedded devices and mobile phones on the low end, to enterprise servers and supercomputers on the high end. While less common, Java applets are sometimes used to provide improved and secure functions while browsing the World Wide Web on desktop computers.
As per an estimate, nearly 3 billion devices use JAVA worldwide. The demand for JAVA professionals has never seen downtrend since its inception in the IT industry. Since JAVA can be used to develop software for wide range of devices starting from embedded systems, to complex web server applications, a JAVA professional can fit into most of the software development companies.
Nonetheless, if you know JAVA, you can also opt for becoming a mobile application developer (ANDROID, Blackberry). The rise and growth of mobile industry need no explanation and the heat of the technology can be felt from the fact that Android PlayStore, an online portal for Android App distribution, saw nearly 25 billion downloads till Nov' 2012. There are as many as 700k apps in Android market (Play Store) and many more are adding up.
1. Advanced JAVA.
2. Core JAVA.
3. Core J2EE.
4. Advanced J2EE.