public class Person implements Comparable, RPIPerson { public String mName; public int mIDNum; public Person(String name, int id){ mName = name; mIDNum = id; } public String toString(){ return mName + ", " + mIDNum; } public int compareTo(Object rhs){ if (rhs instanceof Person) return this.getIDNumber() - ((Person)rhs).getIDNumber(); else return -1; } public int getIDNumber() { return mIDNum; } }