title: Extend a java class from one file in another java file
body: <p>How can I include one java file into another java file? </p>
  
  <p>For example:
  If I have 2 java file one is called <code>Person.java</code> and one is called <code>Student.java</code>. How can I include <code>Person.java</code> into <code>Student.java</code> so that I can extend the class from <code>Person.java</code> in <code>Student.java</code></p>