Java泛型不能使用instanceOf

由于编译器使用类型擦除，
所以运行时无法跟踪类型参数，所以不能使用instanceOf运算符

  
InfoClass<Integer> integerInfoClass = new InfoClass<Integer>();

//Compiler Error:
//Cannot perform instanceof check against
//parameterized type InfoClass<Integer>.
//Use the form InfoClass<?> instead since further
//generic type information will be erased at Runtime
if(integerInfoClass instanceof InfoClass<Integer>) { }