Java.util.Scanner.nextLong()


描述

所述java.util.Scanner.nextLong(int radix)方法扫描输入作为长的下一个标记。如果下一个令牌无法转换为有效的long值,则此方法将抛出InputMismatchException,如下所述。如果翻译成功,扫描仪将超过匹配的输入。

声明

以下是java.util.Scanner.nextLong()方法的声明

public long nextLong(int radix)

参数

radix - 用于将标记解释为int值的基数

返回值

此方法返回从输入扫描的长扫描

异常

InputMismatchException - 如果下一个标记与Integer正则表达式不匹配,或者超出范围

NoSuchElementException - 如果输入用尽

IllegalStateException - 如果此扫描程序已关闭

实例

以下示例显示了java.util.Scanner.nextLong()方法的用法。

package com.tutorialspoint;

import java.util.*;

public class ScannerDemo {
   public static void main(String[] args) {

      String s = "Hello World! 3 + 3.0 = 6.0 true ";
      Long l = 13964599874l;
      s = s + l;

      // create a new scanner with the specified String Object
      Scanner scanner = new Scanner(s);

      // find the next long token and print it
      // loop for the whole scanner
      while (scanner.hasNext()) {

         // if no long is found, print "Not Found:" and the token
         System.out.println("Not Found :" + scanner.next());

         // if the next is a long, print found and the long with radix 20
         if (scanner.hasNextLong()) {
            System.out.println("Found :" + scanner.nextLong(20));
         }
      }

      // close the scanner
      scanner.close();
   }
}

让我们编译并运行上面的程序,这将产生以下结果

Not Found :Hello
Not Found :World!
Found :3
Not Found :+
Not Found :3.0
Not Found :=
Not Found :6.0
Not Found :true
Found :12014353515344