问题

import java.util.InputMismatchException;
import java.util.Scanner;

class Main {
  public static void main(String[] args) {
    
    //init variables
    String name = "";
    int age = -1;
    int height_in_cm = -1;

    //Init Scanner
    Scanner input = new Scanner(System.in);

    //Get the input from the user and save to the initiated variables above.
    System.out.print("Please enter your name: ");
    name = input.nextLine();
    try{
    System.out.printf("Hey, %s. How old are you?: ", name);
    age = input.nextInt();
    } catch (InputMismatchException e){
        System.out.printf("Agh! Sorry %s. We were expecting a number made up of digits between 0-9. Try again for us? \n How old are you?: ", name);
        age = input.nextInt();
    }
    System.out.print("And finally, what is your height in CM?: ");
    height_in_cm = input.nextInt();

    //close the scanner to protect from resource leaks.
    input.close();


  }
}```

<details>
<summary>英文:</summary>

I am just learning Java and I&#39;m struggling with Exception handling. I am trying to write a quick program that takes some inputs and exports them converted into different units. 

I am using Scanner to take the input and I&#39;m trying to protect against an InputMisatchException but despite putting a try-catch block around it to handle the exception it still exits. the code is bellow. Hope you can help! Thanks in advance.

```import java.io.*;
import java.util.InputMismatchException;

import java.util.Scanner;

class Main {
  public static void main(String[] args) {
    
    //init variables
    String name = &quot;&quot;;
    int age = -1;
    int height_in_cm = -1;

    //Init Scanner
    Scanner input = new Scanner(System.in);

    //Get the input from the user and save to the initiated variables above.
    System.out.print(&quot;Please enter your name: &quot;);
    name = input.nextLine();
    try{
    System.out.printf(&quot;Hey, %s. How old are you?: &quot;, name);
    age = input.nextInt();
    } catch (InputMismatchException e){
        System.out.printf(&quot;Agh! Sorry %s. We were expecting a number made up of digits between 0-9. Try again for us? \n How old are you?: &quot;, name);
        age = input.nextInt();
    }
    System.out.print(&quot;And finally, what is your height in CM?: &quot;);
    height_in_cm = input.nextInt();

    //close the scanner to protect from resource leaks.
    input.close();


  }
}```

</details>


# 答案1
**得分**: 0

你需要在以下代码周围添加一个额外的 try-catch 块：

```java
height_in_cm = input.nextInt();

否则，你将会得到另一个异常！

height_in_cm = input.nextInt();

答案2

得分: 0

以下是您要翻译的内容：

异常的原因是，在第一次抛出异常时，扫描器（input）不会更新其指针，因此catch块中的input.nextInt()读取的是与try块中的input.nextInt()相同的输入。

为了解决这个问题，在catch块中在读取int值之前添加input.nextLine()。

try {
    System.out.printf("嘿，%s。你多大了？：", name);
    age = input.nextInt();
} catch (InputMismatchException e) {
    System.out.printf("啊！抱歉，%s。我们期望输入一个由0-9之间的数字组成的数字。能再试一次吗？\n你多大了？：", name);
    input.nextLine();
    age = input.nextInt();
}

 try{
		System.out.printf("Hey, %s. How old are you?: ", name);
		age = input.nextInt();
	} catch (InputMismatchException e){
		System.out.printf("Agh! Sorry %s. We were expecting a number made up of digits between 0-9. Try again for us? \n How old are you?: ", name);
		input.nextLine();
		age = input.nextInt();
	}

答案3

得分: 0

代码部分不要翻译，只返回翻译好的部分：

"The reason is that you are catching the error in the catch block. Try to implement a loop for it. Also remember to clear the buffer using input.next(); otherwise you will encounter infinite-loop

do
{
try
{
System.out.printf("嘿，%s。你多大了？：", name);
age = input.nextInt();
stop = true;
}
catch (InputMismatchException e)
{
System.out.printf("啊！对不起%s。我们期望输入一个由0-9之间的数字组成的数字。再试一次好吗？\n你多大了？：", name);
input.next(); // 清空缓冲区。否则会导致无限循环
}
} while( !stop );"

do
{
    try
    {
        System.out.printf("Hey, %s. How old are you?: ", name);
        age = input.nextInt();
        stop = true;
    } 
    catch (InputMismatchException e)
    {
        System.out.printf("Agh! Sorry %s. We were expecting a number made up of digits between 0-9. Try again for us? \n How old are you?: ", name);
        input.next(); // Clearing the buffer. This is important otherwise Infinite Loop will occur
    }
} while( !stop );