2017-05-23 01:38:02 +02:00

49 lines
1.6 KiB
Java

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Created by Alexis on 28-Apr-17.
* With Marker interface idea is to make empty interface and extend it.
* Basically it is just to identify the special objects from normal objects.
* Like in case of serialization , objects that need to be serialized must implement serializable interface
* (it is empty interface) and down the line writeObject() method must be checking
* if it is a instance of serializable or not.
* <p>
* Marker interface vs annotation
* Marker interfaces and marker annotations both have their uses,
* neither of them is obsolete or always better then the other one.
* If you want to define a type that does not have any new methods associated with it,
* a marker interface is the way to go.
* If you want to mark program elements other than classes and interfaces,
* to allow for the possibility of adding more information to the marker in the future,
* or to fit the marker into a framework that already makes heavy use of annotation types,
* then a marker annotation is the correct choice
*/
public class App {
/**
* Program entry point
*
* @param args command line args
*/
public static void main(String[] args) {
final Logger logger = LoggerFactory.getLogger(App.class);
Guard guard = new Guard();
Thief thief = new Thief();
if (guard instanceof Permission) {
guard.enter();
} else {
logger.info("You have no permission to enter, please leave this area");
}
if (thief instanceof Permission) {
thief.steal();
} else {
thief.doNothing();
}
}
}