Java - Inheritance (Method Overriding)

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// Regular class inheritance
package com.peter.inheritance;

public class Main {

    public static void main(String[] args) {
        Son ObSon = new Son();
        ObSon.func();
                ObSon.father_func();    // inheritance from Father class

        Father ObFather = new Father();
        ObFather.func();
    }
}
------------------
package com.peter.inheritance;

public class Father {
    public void func() {
        System.out.println("Father");
    }

public void father_func() {
        System.out.println("Father_Func");
    }

}
-------------------
package com.peter.inheritance;

public class Son extends Father {
    public void func() {             // Overriding
        System.out.println("Son");
    }
}

// Abstract class inheritance
package com.peter.inheritance;

public class Main {

    public static void main(String[] args) {
        Son ObSon = new Son();
        ObSon.func();
    }
}
-----------------------------
package com.peter.inheritance;

abstract class Father {
    abstract void func();
}

----------------------------
package com.peter.inheritance;

public class Son extends Father {
    public void func() {           // Overriding not Needed!!
        System.out.println("Son");
    }
}


// Interface class inheritance
package com.peter.inheritance;

public class Main {

    public static void main(String[] args) {
        Son ObSon = new Son();
        ObSon.func();
    }
}
-------------------------------
package com.peter.inheritance;

public interface Father {
    abstract void func();
}

-----------------------------
package com.peter.inheritance;

public class Son implements Father {
    public void func() {                  // Overriding Needed!!
        System.out.println("Son");
    }
}

// Anonymous Inner Class Inheritance
package com.peter.inheritance;

public class Main {

    public static void main(String[] args) {
        Son ObSon = new Son(){                         // Inner Class
            public void func(){                    // Method Overriding
                System.out.println("Main");
            }
        };

        ObSon.func();
    }
}
-------------------------------
package com.peter.inheritance;

public interface Father {
    abstract void func();
}

-----------------------------
package com.peter.inheritance;

public class Son implements Father {
    public void func() {                  // Overriding Needed!!
        System.out.println("Son");
    }
}