give me your help bro :(

Question about the task

All that moves

Java Core, Level 3, Lesson 2

Under discussion

i dont understand how i can ddo this, but i understand all process

1. Create a CanMove interface that has a speed method.
2. The speed method must return a Double and should not accept any arguments.
3. Make the CanFly interface inherit the CanMove interface.
4. Add the speed method to the CanFly interface.
5. The speed method must return a Double and accept one CanFly argument.

Requirements:

The Solution class must declare a CanMove interface.
The Solution class must declare a CanFly interface.
The CanFly interface must inherit the CanMove interface.
The CanMove interface must declare a speed method with no parameters and must return a Double.
The CanFly interface must declare a speed method with one CanFly parameter and must return a Double.

public class Solution { public static void main(String[] args) { } interface CanMove{ Double spd = 1.1; default Double speed() { return spd; } } interface CanFly extends CanMove { public void speed(double x){ } } }

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rydenfoo

Level 20 , Birmingham, UK

15 August 2019, 11:14

Hi! First, you don't need to implement the speed method, you just need to declare it. For instance, to declare a regular void method (returns void), you would do this:

void speed();

But in the interface CanMove, you don't want a "void", you want a "Double" (return a Double). So make the change :) Then use the same logic for CanFly: again, your method needs to return a "Double", but must also receive a CanFly parameter speed. When you pass an object Cat, for instance, you do this:

someMethod(Cat kitty)

or for a String:

someMethod(String str)

But you want a CanFly parameter, so...