关于泛型：Java 8 – Wildcard扩展，BiPredicate无法正常工作

Java 8 - Wildcard extends with BiPredicate not working

本问题已经有最佳答案，请猛点这里访问。

我不知道为什么它不起作用。

Eclipse中的错误消息：方法测试(水果，捕获1-of？bipredicate类型中的extends水果)不适用于参数(水果、芒果)

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import java.util.function.BiPredicate;

public class PredTest {

public static void main(String[] args) {

class Fruit {
public String name;
public String color;
Fruit(String name) {this.name = name; }
};

class Apple extends Fruit {
Apple() {super("Apple");}
};
class Mango extends Fruit {
Mango() {super("Mango");}
};

BiPredicate<Fruit, ? extends Fruit> tester = (f, nf) -> {
System.out.println(nf.name);
return true;
};
Fruit f = new Fruit("Not named");
Apple a = new Apple();
Mango m = new Mango();

// ########### I see error in the below line
System.out.println(tester.test(f, m));

}

}