我正在努力實現下一個目標：家長：public class Animal { private List<Animal> relatives; public List<Animal> getRelatives() { return relatives; } public void setRelatives(List<Animal> relatives) { this.relatives = relatives; }}孩子：public class Dog extends Animal { private List<Dog> relatives; public List<Dog> getRelatives() { return relatives; } public void setRelatives(List<Dog> relatives) { this.relatives = relatives; }}但由于某種原因，我收到方法沖突的錯誤。這是否可以通過繼承而不使用泛型類型來實現？
2 回答
郎朗坤
TA貢獻1921條經驗 獲得超9個贊
您實際上不需要覆蓋/復制子類中的任何內容。
class Animal<Relative extends Animal<?>> {
private List<? extends Relative> relatives;
public List<? extends Relative> getRelatives() {
return relatives;
}
public void setRelatives(List<? extends Relative> relatives) {
this.relatives = relatives;
}
}
class Dog extends Animal<Dog> {}
楊魅力
TA貢獻1811條經驗 獲得超6個贊
您可以使用泛型并保留relatives在父類中。此外，您應該注意保留意外的修改：
public class Animal<T extends Animal<?>> {
private final List<T> relatives = new ArrayList<>();
public final List<T> getRelatives() {
return relatives.isEmpty() ? Collections.emptyList() : Collections.unmodifiableList(relatives);
}
public final void addRelative(T relative) {
Objects.requireNonNull(relative);
relatives.add(relative);
}
}
public class Dog extends Animal<Dog> {
// just for test
public List<Dog> getRelativesDogs() {
return super.getRelatives();
}
// just for test
public void addRelativeDog(Dog dog) {
super.addRelative(dog);
}
}
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