// generics/EpicBattle.java

// (c)2021 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

// Bounds in Java generics

import java.util.*;

interface SuperPower {}

interface XRayVision extends SuperPower {

void seeThroughWalls();

}

interface SuperHearing extends SuperPower {

void hearSubtleNoises();

}

interface SuperSmell extends SuperPower {

void trackBySmell();

}

class SuperHero<POWER extends SuperPower> {

POWER power;

SuperHero(POWER power) { this.power = power; }

POWER getPower() { return power; }

}

class SuperSleuth<POWER extends XRayVision>

extends SuperHero<POWER> {

SuperSleuth(POWER power) { super(power); }

void see() { power.seeThroughWalls(); }

}

class

CanineHero<POWER extends SuperHearing & SuperSmell>

extends SuperHero<POWER> {

CanineHero(POWER power) { super(power); }

void hear() { power.hearSubtleNoises(); }

void smell() { power.trackBySmell(); }

}

class SuperHearSmell

implements SuperHearing, SuperSmell {

@Override public void hearSubtleNoises() {}

@Override public void trackBySmell() {}

}

class DogPerson extends CanineHero<SuperHearSmell> {

DogPerson() { super(new SuperHearSmell()); }

}

public class EpicBattle {

// Bounds in generic methods:

static <POWER extends SuperHearing>

void useSuperHearing(SuperHero<POWER> hero) {

hero.getPower().hearSubtleNoises();

}

static <POWER extends SuperHearing & SuperSmell>

void superFind(SuperHero<POWER> hero) {

hero.getPower().hearSubtleNoises();

hero.getPower().trackBySmell();

}

public static void main(String[] args) {

DogPerson dogPerson = new DogPerson();

useSuperHearing(dogPerson);

superFind(dogPerson);

// You can do this:

List<? extends SuperHearing> audioPeople;

// But you can't do this:

// List<? extends SuperHearing & SuperSmell> dogPs;

}

}