Java 泛型 类型参数推断和显示类型说明
public class New {/** * 这就是类型推断 */public static <K, V> Map<K, V> map() {return new HashMap<K, V>();}public static <T> List<T> list() {return new ArrayList<T>();}public static <T> LinkedList<T> lList() {return new LinkedList<T>();}public static <T> Set<T> set() {return new HashSet<T>();}public static <T> Queue<T> queue() {return new LinkedList<T>();}public static void main(String[] args) {Map<Person, List<? extends Person>> pet = New.map();f(pet);f(New.<Person, List<? extends Person>> map());// 显示的类型说明-- 静态方法在点(.)操作符前用类名，非静态this}static void f(Map<Person, List<? extends Person>> pet) {System.out.println(pet);}}