Thread: Triple Inheritance

I remember that i had read that multi inheritance is not allowed in JAVA.So imagine the hierarchy is like this in my code

A
|
|
v
B
|
|
v
C

An ugly way to make C inherit what comes from A is to write the vary same functions to function B and to call the functions of A there.Isn't there a more elegant-smart way to do this?

The variables can not be inheritted in any way?

I also thought that we were able to use the same functionality with the interfaces(a class can implement two or more intrefaces if wanted) but i do not think that is works for the class inheritance.

Your original post suggests you want B to extend A, and C to extend B. And that's fine - ie the following compiles:

class A {}
class B extends A {}
class C extends B {}

Java doesn't allow classes to inherit the implementation of multiple direct or immediate super classes, but that's all. Animal species, genera etc are the same: but a cat can be-a feline and a mammal.

Copeg i also thought of what you said but i think is too much.

pbrocway2 check this example.

Inheritance.java

package inheritance;
 
public class Inheritance {
    public static void main(String[] args) {
        C test=new C();
        test.foo();
        test.bla();
    }
}

A.java

package inheritance;
 
public class A {
    private int year;
    public  int getYear(){
        return year;
    }
}

B.java

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package inheritance;
 
/**
 *
 * @author User
 */
public class B extends A {
    private int day;
 
    public final int getDay(){
        return day;
    }
 
    public void foo(){
        int year=super.getYear();
        day=15;
    }
 
}

C.java

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package inheritance;
 
/**
 *
 * @author User
 */
public class C extends B {
    public void bla(){
        int day=super.getDay();
        int year=super.getYear();
    }
}

this works good but in a larger program i have now i can not achieve this.Something else might be the problem.I am going to look it up
thanks

You don't need those "super" keywords.

Instances of C are also instances of B and they are also instances of A. So it is perfectly acceptable (and clearer) to write

package inheritance;
 
public class C extends B {
    public void bla(){
        int day = getDay();
        int year = getYear();
    }
}

There are some options, ranging from elegant to down right ugly, depending on the need for this "double inheritance" (I believe it's not triple). Without a hard example, I don't think I can really figure out the best way to achieve the desired effect.