interface InterfaceA {
void increment();
}
class ClassA implements InterfaceA {
private int i = 0;
public void increment() {
i++;
System.out.println(i);
}
}
class ClassB {
void increment() {
System.out.println("Other operation");
}
static void f(ClassB mi) {
mi.increment();
}
}
class ClassC extends ClassB {
private int i = 0;
private void incr() {
i++;
System.out.println(i);
}
private class Closure implements InterfaceA {
public void increment() {
incr();
}
}
InterfaceA getCallbackReference() {
return new Closure();
}
}
class Caller {
private InterfaceA callbackReference;
Caller(InterfaceA cbh) {
callbackReference = cbh;
}
void go() {
callbackReference.increment();
}
}
public class MainClass {
public static void main(String[] args) {
ClassA c1 = new ClassA();
ClassC c2 = new ClassC();
ClassB.f(c2);
Caller caller1 = new Caller(c1);
Caller caller2 = new Caller(c2.getCallbackReference());
caller1.go();
caller2.go();
}
}