Java Scanner ioException()方法及示例

java.util.Scanner 类的 ioException() 方法返回该Scanner的底层Readable最后抛出的IOException。如果不存在这样的异常，该方法返回null。

语法

public IOException ioException()

返回值： 该函数返回该扫描器的可读性所抛出的最后一个异常。

下面的程序说明了上述函数。

程序1 :

// Java program to illustrate the
// ioException() method of Scanner class in Java
// without parameter
  
import java.util.*;
  
public class GFG1 {
    public static void main(String[] argv)
        throws Exception
    {
  
        String s = "gfg geeks!";
  
        // create a new scanner
// with the specified String Object
        Scanner scanner = new Scanner(s);
  
        // print the line
        System.out.println("" + scanner.nextLine());
  
        // check if there is an IO exception
        System.out.println("" + scanner.ioException());
  
        // close the scanner
        scanner.close();
    }
}

输出:

gfg geeks!
null

程序2

// Java program to illustrate the
// ioException() method of Scanner class in Java
// without parameter
  
import java.util.*;
  
public class GFG1 {
    public static void main(String[] argv)
        throws Exception
    {
  
        String s = "gopal dave!";
  
        // new scanner with the specified String Object
        Scanner scanner = new Scanner(s);
  
        // print the line
        System.out.println("" + scanner.nextLine());
  
        // checks if there is an IO exception
        System.out.println("" + scanner.ioException());
  
        // close the scanner
        scanner.close();
    }
}

输出: