This is about as simple as a Java program can be and still make some use of classes.
class Person { String name; int age = 20; void birthday () { age++; System.out.println (name + " is now "+ age); } } public class People { public static void main (String args []) { Person john; john = new Person (); Person mary = new Person (); john.name = "John Doe"; john.birthday (); } } |
Compiling produces these two bytecode files:javac People.java
People.class
Person.class
java People
John Doe is now 21