Shell we make a class as an interface?

Question

shell we make a class as an interface then how ? give me one example

Answer 1

shell we make a class as an interface then how ?What do you mean? Currently something is a class and you want to change that type to an interface?
If so, then as for "shall you," I don't know. That depends on your needs, time, and skill level.
give
me one exampleAssuming you mean what I think you mean, it might be something like this:
// BEFORE
public class Foo {
    public void doStuff() { /* do some stuff */ }
Foo foo =new Foo();
foo.doStuff();
// AFTER
public interface Foo {
    void doStuff();
public class SimpleFoo implements Foo {
    public void doStuff() { /* do some stuff */ }
Foo foo = new SimpleFoo();
foo.doStuff();