Java Scanner - nextInt() Method

The java.util.Scanner.nextInt() method is used to scan the next token of the input as an int. This method will throw InputMismatchException if the next token cannot be translated into a valid int value as described below. If the translation is successful, the scanner advances past the input that matched.

Syntax

public int nextInt(int radix)

Parameters

Return Value

Returns the int scanned from the input.

Exception

• Throws InputMismatchException, if the next token does not match the Float regular expression, or is out of range.
• Throws NoSuchElementException, if input is exhausted.
• Throws IllegalStateException, if this scanner is closed.

Example:

In the example below, the java.util.Scanner.nextInt() method is used to scan the next token of the input as an int.

import java.util.*;

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

    //String to scan
    String MyString = "Hello World 10 + 20 = 30.0";

    //creating a Scanner
    Scanner MyScan = new Scanner(MyString);

    while(MyScan.hasNext()) {
      //if the next is an int
      //print the int with radix 16
      if(MyScan.hasNextInt(16))
        System.out.println("Int value is: "+ MyScan.nextInt(16));
      //if the next is not an int
      else
        System.out.println("No Int Value found: "+ MyScan.next());
    }

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

The output of the above code will be:

No Int Value found: Hello
No Int Value found: World
Int value is: 16
No Int Value found: +
Int value is: 32
No Int Value found: =
No Int Value found: 30.0