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Java Scanner nextBoolean() Method with Example

Scanner Class nextBoolean() method: Here, we are going to learn about the nextBoolean() method of Scanner Class with its syntax and example.
Submitted by Preeti Jain, on February 18, 2020

Scanner Class nextBoolean() method

• nextBoolean() method is available in java.util package.
• nextBoolean() method is used to scans the next token of the input scanned into a boolean value.
• nextBoolean() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
• nextBoolean() method may throw an exception at the time of returning a Boolean value.
  • InputMismatchException: This exception may throw when the next token input mismatch.
  • NoSuchElementException: This exception may throw when no such element exists.
  • IllegalStateException: This exception may throw when this Scanner is not opened.

Syntax:

    public boolean nextBoolean();

Parameter(s):

• It does not accept any parameter.

Return value:

The return type of the method is boolean, it returns true when the valid boolean value scanned from the input otherwise it returns false.

Example:

// Java program to demonstrate the example 
// of boolean nextBoolean() method of Scanner 

import java.util.*;

public class NextBooleanOfScanner {
    public static void main(String[] args) {
        String str = "Hi, true IncludeHelp! 8 + 2.0 = 10.0";

        // Instantiate Scanner with the 
        // given str
        Scanner sc = new Scanner(str);

        // Loop for scanning the boolean
        // token input
        while (sc.hasNext()) {
            // if boolean then display it
            if (sc.hasNextBoolean()) {
                System.out.println("Boolean Exists: " + sc.nextBoolean());
            }
            sc.next();
        }

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

Output

Boolean Exists: true