package com.m01.program.maven_1; public class Test { public static void main(String[] args) { getData(new Fx(1)); getData(new Fx("hah")); } public static void getData(Fx<?> temp){//? :类型通配符 System.out.println(temp.ob); } } class Fx<T>{ public T ob; public Fx(T ob){ this.ob=ob; } }