supertypewildcards.java

来自「Thinking in JAVA第四版源代码」· Java 代码 · 共 11 行

//: generics/SuperTypeWildcards.java
import java.util.*;

public class SuperTypeWildcards {
  static void writeTo(List<? super Apple> apples) {
    apples.add(new Apple());
    apples.add(new Jonathan());
    // apples.add(new Fruit()); // Error
  }
} ///:~