Java Scanner nextShort()方法及示例

java.util.Scanner 类的 nextShort(radix) 方法将输入的下一个标记扫描为一个短码。如果翻译成功，扫描器就会前进到匹配的输入。如果没有传递参数radix，那么它的行为类似于nextShort(radix)，其中radix被假定为默认radix。

语法

public short nextShort()

参数： 该函数接受一个参数 radix ，用于将令牌解释为一个短值。

返回值： 该函数返回从输入中扫描出的短值。

异常： 该函数抛出三种异常，如下所述。

• InputMismatchException： 如果下一个标记不符合Integer正则表达式，或者超出了范围。
• NoSuchElementException： 如果输入已用尽，则抛出。
• IllegalStateException： 如果该扫描器被关闭，则抛出。

下面的程序说明了上述功能。

程序1 :

// Java program to illustrate the
// nextShort() 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 9 + 6 = 12.0";
 
        // create a new scanner
        // with the specified String Object
        Scanner scanner = new Scanner(s);
 
        while (scanner.hasNext()) {
 
            // if the next is a short,
            // print found and the short
            if (scanner.hasNextShort()) {
                System.out.println("Found Short value :"
                                   + scanner.nextShort());
            }
 
            // if no short is found,
            // print "Not Found:" and the token
            else {
                System.out.println("Not found short value :"
                                   + scanner.next());
            }
        }
        scanner.close();
    }
}

输出

Not found short value :Gfg
Found Short value :9
Not found short value :+
Found Short value :6
Not found short value :=
Not found short value :12.0

程序2

// Java program to illustrate the
// nextShort() method of Scanner class in Java
// with parameter
 
import java.util.*;
 
public class GFG1 {
    public static void main(String[] argv)
        throws Exception
    {
 
        String s = "Gfg 9 + 6 = 12.0";
 
        // create a new scanner
        // with the specified String Object
        Scanner scanner = new Scanner(s);
 
        while (scanner.hasNext()) {
 
            // if the next is a short,
            // print found and the short
            if (scanner.hasNextShort()) {
                System.out.println("Found Short value :"
                                   + scanner.nextShort(12));
            }
 
            // if no short is found,
            // print "Not Found:" and the token
            else {
                System.out.println("Not found short value :"
                                   + scanner.next());
            }
        }
        scanner.close();
    }
}

输出

Not found short value :Gfg
Found Short value :9
Not found short value :+
Found Short value :6
Not found short value :=
Not found short value :12.0

程序3： 演示InputMismatchException

// Java program to illustrate the
// nextShort() method of Scanner class in Java
// InputMismatchException
 
import java.util.*;
 
public class GFG1 {
    public static void main(String[] argv)
        throws Exception
    {
 
        try {
 
            String s = "Gfg 9 + 6 = 12.0";
 
            // create a new scanner
            // with the specified String Object
            Scanner scanner = new Scanner(s);
 
            while (scanner.hasNext()) {
 
                // if the next is a short,
                // print found and the short
                // since the value 60 is out of range
                // it throws an exception
 
                System.out.println("Next Short value :"
                                   + scanner.nextShort());
            }
            scanner.close();
        }
        catch (Exception e) {
            System.out.println("Exception thrown: " + e);
        }
    }
}

输出

Exception thrown: java.util.InputMismatchException

程序4： 演示NoSuchElementException

// Java program to illustrate the
// nextShort() method of Scanner class in Java
// NoSuchElementException
 
import java.util.*;
 
public class GFG1 {
    public static void main(String[] argv)
        throws Exception
    {
 
        try {
 
            String s = "Gfg";
 
            // create a new scanner
            // with the specified String Object
            Scanner scanner = new Scanner(s);
 
            // Trying to get the next short value
            // more times than the scanner
            // Hence it will throw exception
            for (int i = 0; i < 5; i++) {
 
                // if the next is a short,
                // print found and the short
                if (scanner.hasNextShort()) {
                    System.out.println("Found Short value :"
                                       + scanner.nextShort());
                }
 
                // if no short is found,
                // print "Not Found:" and the token
                else {
                    System.out.println("Not found short value :"
                                       + scanner.next());
                }
            }
            scanner.close();
        }
        catch (Exception e) {
            System.out.println("Exception thrown: " + e);
        }
    }
}

输出

Not found short value :Gfg
Exception thrown: java.util.NoSuchElementException

程序5： 演示IllegalStateException

// Java program to illustrate the
// nextShort() method of Scanner class in Java
// IllegalStateException
 
import java.util.*;
 
public class GFG1 {
    public static void main(String[] argv)
        throws Exception
    {
 
        try {
 
            String s = "Gfg 9 + 6 = 12.0";
 
            // create a new scanner
            // with the specified String Object
            Scanner scanner = new Scanner(s);
 
            // close the scanner
            scanner.close();
            System.out.println("Scanner Closed");
 
            System.out.println("Trying to get "
                               + "next Short value");
 
            while (scanner.hasNext()) {
 
                // if the next is a short,
                // print found and the short
                if (scanner.hasNextShort()) {
                    System.out.println("Found Short value :"
                                       + scanner.nextShort());
                }
 
                // if no short is found,
                // print "Not Found:" and the token
                else {
                    System.out.println("Not found short value :"
                                       + scanner.next());
                }
            }
        }
        catch (Exception e) {
            System.out.println("Exception thrown: " + e);
        }
    }
}

输出

Scanner Closed
Trying to get next Short value
Exception thrown: java.lang.IllegalStateException: Scanner closed

**参考资料: ** https://docs.oracle.com/javase/7/docs/api/java/util/Scanner.html#nextShort()