Need Assistance on Assignment

I have an assigment dealing with Java class date. I will attach the link as well. It deals with time. I need an program source code example that shows inheritance and polymorphism.

java.util
Class Date
java.lang.Object
  java.util.Date

All Implemented Interfaces:
Cloneable, Comparable, Serializable
Direct Known Subclasses:
Date, Time, Timestamp

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