1 year and 1-3 years are the primary stages.

2, 3-5 years is the intermediate stage,

3, 5- 10 years is an advanced stage.

4./kloc-More than 0/0 years as a technical expert, technical director, project manager, etc. Java is an object-oriented programming language. At the beginning of 1990, james gosling and others developed the prototype of Java language, which was originally named Oak.