public interface Behavior {
void perform();
}
public class Implementation implements Behavior {
public void perform() {
System.out.println("Original behavior");
}
}
public class AdjustableBehaviorHandler implements InvocationHandler {
private Behavior targetBehavior;
public AdjustableBehaviorHandler(Behavior behavior) {
this.targetBehavior = behavior;
}
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
System.out.println("Before method");
Object result = method.invoke(targetBehavior, args);
System.out.println("After method");
return result;
}
}
public class AdjustableBehaviorFactory {
public static Behavior createAdjustableBehavior() {
Behavior behavior = new Implementation();
AdjustableBehaviorHandler handler = new AdjustableBehaviorHandler(behavior);
Behavior proxy = (Behavior) Proxy.newProxyInstance(
behavior.getClass().getClassLoader(),
behavior.getClass().getInterfaces(),
handler);
return proxy;
}
}
public class Main {
public static void main(String[] args) {
Behavior behavior = AdjustableBehaviorFactory.createAdjustableBehavior();
behavior.perform();
}
}
