Error occurs when I am ready to pass a function in MyInterface

Hello experts,
I have MyInterface with 2 classes A and B, which is implementing MyInterface.
Then I stated 2 objects: 1. MyInterface a = new A (), 2. MyInterface b = new B ().
When I am ready to pass a function – function doSomething(A a){}, the following error occurs:
This is my code:
public interface MyInterface {}
public class A implements MyInterface{}
public class B implements MyInterface{}
public class Tester {
public static void main(String[] args){
MyInterface a = new A();
MyInterface b = new B();
test(b);
}
public static void test(A a){
System.out.println("A");
}
public static void test(B b){
System.out.println("B");
}
}
My issue is that I am receiving from a few component interfaces which may be in all types of classes. Also, I want to write function for every class.
I need to solve this error. I need your help.
Please give me a solution.
Thanks.
