generictoytest.java

来自「网络学习资源 Java编程思想_第4版_源代码」· Java 代码 · 共 17 行

//: typeinfo/toys/GenericToyTest.java
// Testing class Class.
package typeinfo.toys;

public class GenericToyTest {
  public static void main(String[] args) throws Exception {
    Class<FancyToy> ftClass = FancyToy.class;
    // Produces exact type:
    FancyToy fancyToy = ftClass.newInstance();
    Class<? super FancyToy> up = ftClass.getSuperclass();
    // This won't compile:
    // Class<Toy> up2 = ftClass.getSuperclass();
    // Only produces Object:
    Object obj = up.newInstance();
  }
} ///:~