Public, Private, Protected, Default and Final variables and methods.

 package Main;

package Main;

public class Car {
    public static int a;
    private static int b;
    protected static int c;
    static int d;
    int e;
    public int f;

    public static int getB() {
        return b;
    }

    public static void setB(int b) {
        Car.b = b;
    }

    public static void foo1() {

    }

    public void foo2() {

    }

    private static void foo3() {

    }

    private void foo4() {

    }

    void foo5() {

    }
    
    public void foo6(){
        
    }
}

package Another;

import Main.Car;

public class BMW extends Car {

}
1. a : BMW.a and Car.a;
2. b : BMW.getB() and Car.getB();
3. c : BMW.c and Car.c;
4. d : Car.d; BMW.d; But in an another package it is impossible to call them.
5. e : Car c = new Car(); c.e. BMW b = new BMW(); b.e; But in another package it is
impossible to call them.
6. f : Car c = new Car(); BMW b = new BMW(); c.f and b.f;
7. foo1 : Car.foo1(); and BMW.foo1();
8. foo2 : c.foo2(): and b.foo2();
9. foo3 : this method only could be used inside class Car.
10. foo4 : this method as well could be used inside class Car.
11. foo5 : c.foo5(); b.foo5(); Outside the package it is impossible to use.
12. foo6 : c.foo6(): and b.foo6();
I guess this is clearer now.

*Final keyword. Final variable has to be initialized. Final method can not be 
overrrided. Final class can not be extended.