Java Scanner nextInt（）方法与示例

旧城等待， 2023-03-05 13:29 7阅读 0赞

## 扫描器类的nextInt()方法 **(**Scanner Class nextInt() method**)** ##

**Syntax:**

**句法：**

public int nextInt();
        public int nextInt(int rad);

*  **nextInt() method** is available in java.util package.
    
    **nextInt()方法**在java.util包中可用。
 *  **nextInt() method** is used to read the next token of the input as an int value at the implicit radix (rad) of this Scanner.
    
    **nextInt()方法**用于读取输入的下一个标记，作为此Scanner的隐式基数(rad)处的int值。
 *  **nextInt(int rad) method** is used to read the next token of the input as an int value at the explicit or given radix (rad) of this Scanner.
    
    **nextInt(int rad)方法**用于读取输入的下一个标记作为此Scanner的显式或给定基数(rad)的int值。
 *  These methods may throw an exception at the time of representing input as an int.
    
    在将输入表示为int时，这些方法可能会引发异常。
    
     *  **InputMismatchException**: This exception may throw when the next token of the input mismatch.**InputMismatchException** ：当输入的下一个标记不匹配时，可能引发此异常。
     *  **NoSuchElementException**: This exception may throw when no such element exists.**NoSuchElementException** ：如果不存在这样的元素，则可能引发此异常。
     *  **IllegalStateException**: This exception may throw when this Scanner is not opened.**IllegalStateException** ：如果未打开此扫描器，则可能引发此异常。
 *  These are non-static methods, it is accessible with class object & if we try to access these methods with the class name then we will get an error.
    
    这些是非静态方法，可通过类对象访问；如果尝试使用类名称访问这些方法，则会收到错误消息。

**Parameter(s):**

**参数：**

*  In the first case, **nextInt()**,
    
    在第一种情况下， **nextInt()** ，
    
     *  It does not accept any parameter.
 *  In the second case, **nextInt(int rad)**,
    
    在第二种情况下， **nextInt(int rad)** ，
    
     *  int rad – represents the radix used to manipulate the token as an int.
     *  int rad –表示用于将标记作为int操作的基数。

**Return value:**

**返回值：**

In both the cases, the return type of the method is int, it retrieves the int read from the input.

在这两种情况下，方法的返回类型都是int ，它检索从输入读取的int。

**Example 1:**

**范例1：**

// Java program is to demonstrate the example
    // of nextInt() of Scanner
    
    import java.util.*;
    import java.util.regex.*;
    
    public class NextInt {
        
     public static void main(String[] args) {
        
      String str = "Java Programming! 3 * 8= 24 + b";
      byte b = 10;
    
      // Instantiates Scanner
      Scanner sc = new Scanner(str);
    
      while (sc.hasNext()) {
        
       // By using nextInt() method isto
       // return the next token as a 
       // int in the default radix
       if (sc.hasNextInt()) {
        
        int next_i = sc.nextInt();
        System.out.println("sc.nextInt()): " + next_i);
       }
       System.out.println(sc.next());
      }
      // Scanner closed
      sc.close();
     }
    }

**Output**

**输出量**

Java
    Programming!
    sc.nextInt()): 3
    *
    8=
    sc.nextInt()): 24
    +
    b

**Example 2:**

**范例2：**

import java.util.*;
    import java.util.regex.*;
    
    public class NextInt {
        
     public static void main(String[] args) {
        
      String str = "Java Programming! 3 * 8= 24 + b";
      byte b = 10;
    
      // Instantiates Scanner
      Scanner sc = new Scanner(str);
    
      while (sc.hasNext()) {
        
       // By using nextInt(9) method isto
       // return the next token as a 
       // int in the given radix
       if (sc.hasNextInt()) {
        
        int next_i = sc.nextInt(9);
        System.out.println("sc.nextInt(9)): " + next_i);
       }
       System.out.println(sc.next());
      }
      // Scanner closed
      sc.close();
     }
    }

**Output**

**输出量**

Java
    Programming!
    sc.nextInt(9)): 3
    *
    8=
    sc.nextInt(9)): 22
    +
    b

> 翻译自: [https://www.includehelp.com/java/scanner-nextint-method-with-example.aspx][https_www.includehelp.com_java_scanner-nextint-method-with-example.aspx]

[https_www.includehelp.com_java_scanner-nextint-method-with-example.aspx]: https://www.includehelp.com/java/scanner-nextint-method-with-example.aspx