如何處理InputMismatchException？

Question

下面是從布魯斯·埃克爾在Java編程思想爲例，第4版

import java.io.BufferedReader; 
import java.io.StringReader; 
import java.util.Scanner; 

public class BetterRead { 
    public static void main(String[] args) { 
    BufferedReader input = new BufferedReader(new StringReader("Sir Robin of Camelot\n22 1.61803")); 
    Scanner stdin = new Scanner(input); 
    System.out.println("What is your name?"); 
    String name = stdin.nextLine(); 
    System.out.println(name); 
    System.out.println("How old are you? What is your favorite double?"); 
    System.out.println("(input: <age> <double>)"); 
    int age = stdin.nextInt(); 
    double favorite = stdin.nextDouble(); 
    System.out.println(age); 
    System.out.println(favorite); 
    System.out.format("Hi %s.\n", name); 
    System.out.format("In 5 years you will be %d.\n", 
     age + 5); 
    System.out.format("My favorite double is %f.", 
     favorite/2); 
    } 
} 

這裏輸出

What is your name? 
Sir Robin of Camelot 
How old are you? What is your favorite double? 
(input: <age> <double>) 
Exception in thread "main" java.util.InputMismatchException 
    at java.util.Scanner.throwFor(Scanner.java:909) 
    at java.util.Scanner.next(Scanner.java:1530) 
    at java.util.Scanner.nextFloat(Scanner.java:2388) 
    at betterread.BetterRead.main(BetterRead.java:21) 
Java Result: 1 

我很新到Java，但你可以在這個例子中看到如下INT買雙。所以它可能正確。但仍然會拋出InputMismatchException。如何解決這個問題呢？

Answer 1

這個問題似乎是你的語言環境，因爲1.61803似乎不是一個有效的雙倍。試用1,61803。

Answer 2

我覺得行問題可能與Scanner stdin = new Scanner(input);，而不是在這裏試試這個：Scanner stdin = new Scanner(System.in);