Check out example codes for "how to make one java class inherit from another". It will help you in understanding the concepts better.

Code Example 1

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;

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