JAVA INHERITANCE AND INTERFACE DISCUSSION, JAVA CODE TRACING

JAVA Code

package inheritance;




import java.io.*;
import java.sql.*;

interface Vehicle{
//all are the abstract methods.

void changeGear(int a);
void speedUp(int a);
void applyBreaks(int a);
}
class Bicycle implements Vehicle {
int speed;
int gear; // to change gear
@Override
public void changeGear(int newGear){
gear = newGear;
}
//increase speed
public void speedUp(int increment){
speed = speed + increment;
}
//to decrease speed
@Override
public void applyBreaks(int decrement){
speed = speed - decrement;
}


public void printStates(){
System.out.println("speed: " +speed+"gear: "+gear);
}
}

class Bike implements Vehicle{
int speed;
int gear;
@Override

public void changeGear(int newGear){

speed = newGear;
}
@Override
public void speedUp(int increment){

speed = speed + increment;
}
@Override

public void applyBreaks(int decrement){

speed = speed - decrement;

}

public void printStates(){
System.out.println("speed: "+speed+"gear: "+gear);
}
}

class GFG{

public static void main(String[]args){

//creating instance Bicycle
//doing some operations

Bicycle bicycle = new Bicycle();
bicycle.changeGear(2);
bicycle.speedUp(3);
bicycle.applyBreaks(1);

System.out.println("Bicycle present state: ");
bicycle.printStates();



//creating instance of the bike

Bike bike = new Bike();
bike.changeGear(1);
bike.speedUp(4);
bike.applyBreaks(3);


System.out.println("Bike present state: ");
bike.printStates();

}
}