java - 如何检测 Scanner.next() 的第一个标记是否是字符串的整数？

Question

Scanner scan = new Scanner(System.in);
scan.next(); //How to detects if the first token is an int; i.e (Integer.valueOf(scan) 
//will not throw InputMismatchException

我有重载的方法

  void name(String name){
  System.out.println(name)
  }
  void age(int age){
  System.out.println(age)
  }

  void printAgeOrName(){
  System.out.println("Enter name or age");
  String data = scan.next();
 *if(first token of date is int){
  age(Integer.valueOf(date));
  }else{
  name(data);
  }
` }

scan.hastNextInt() 仅适用于输入多个 token 时。我还没有熟悉正则表达式

Answer 1

这就是我最终所做的，感谢 @João Gatto 代码。

 void printAgeOrName(){
      System.out.println("Enter name or age");
      String data = null;
    try{
      data = scan.next();
      age(Integer.valueOf(date)); // will throw NumberFormatException if data is not an integer
    }catch (NumberFormatException n){  // catch and assume data is a string
      name(data);
      }
` }