Show students what code looks like with and without inheritance to motivate the reasons for using it.

students understand inheritance by mapping the code with it back to code without it.

motivate inheritance by helping students see how it makes the code easier to understand.

Example code with inheritance:

// Example taken from:
// http://docs.oracle.com/javase/tutorial/java/IandI/subclasses.html
// Here is the sample code for a possible implementation of a Bicycle class that was presented in the Classes and Objects lesson:
public class Bicycle {
    // the Bicycle class has three fields
     public int cadence;
     public int gear;
     public int speed;

     // the Bicycle class has one constructor
     public Bicycle(int startCadence, int startSpeed, int startGear) {
         gear = startGear;
         cadence = startCadence;
         speed = startSpeed;
     }

     // the Bicycle class has four methods
     public void setCadence(int newValue) {
         cadence = newValue;
         }

     public void setGear(int newValue) {
         gear = newValue;
     }

     public void applyBrake(int decrement) {
         speed -= decrement;
     }

     public void speedUp(int increment) {
     speed += increment;
     }
}

\\ A class declaration for a MountainBike class that is a subclass of Bicycle might look like this:
public class MountainBike extends Bicycle {
     // the MountainBike subclass adds one field
     public int seatHeight;

     // the MountainBike subclass has one constructor
     public MountainBike(int startHeight, int startCadence, int startSpeed, int startGear) {
         super(startCadence, startSpeed, startGear);
         seatHeight = startHeight;
         }

     // the MountainBike subclass adds one method
     public void setHeight(int newValue) {
         seatHeight = newValue;
     }
}