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Collections and Generics

Question : 47 of 53

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Given:

interface Hungry < E > { void munch(E x); }
interface Carnivore < E extends Animal > extends Hungry < E > {}
interface Herbivore extends Hungry < E > {}
abstract class Plant {}
class Grass extends Plant {}
abstract class Animal {}
class Sheep extends Animal implements Herbivore < Sheep > {
  public void munch(Sheep x) {}
}
class Wolf extends Animal implements Carnivore < Sheep > {
  public void munch(Sheep x) {}
}

Which of the following changes (taken separately) would allow this code to compile?(Choose all that apply.)

Change the Carnivore interface to
interface Carnivore < E extends Plant > extends Hungry < E > {}
Change the Herbivore interface to
interface Herbivore < E extends Animal > extends Hungry < E > {}
Change the Sheep class to
class Sheep extends Animal implements Herbivore < Plant > { public void munch(Grass x) {} }
Change the Sheep class to
class Sheep extends Plant implements Carnivore < Wolf > { public void munch(Wolf x) {} }
Change the Wolf class to
class Wolf extends Animal implements Herbivore < Grass > { public void munch(Grass x) {} }
No changes are necessary.

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