point.java

清华大学第二版

public class Point {
	void print() {
		System.out.println("This is the superclass!");
	}

	public static void main(String args[]){
		Point superp = new Point ();
		superp.print();
		Point3d subp = new Point3d();
		subp.print();
	}
}
class Point3d extends Point {
	void print() {
		System.out.println("This is the subclass!");
	}
}