Scanner hasNext() in Java

hasNext(): This method is available in java.util.Scanner class of Java.

Syntax:

boolean java.util.Scanner.hasNext()

This method returns true if this scanner has another token in its input.

Parameters: NA

Returns: true if and only if this scanner has another token.

Throws:

IllegalStateException - if this scanner is closed

Approach 1: When no exception

Java

import java.util.Scanner;

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

        String source = "Hello World";
        Scanner scanner = new Scanner(source);

        System.out.println(scanner.hasNext());

        scanner.close();
    }
}

Output:

true


Approach 2: IllegalStateException 

Java

import java.util.Scanner;

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

        String source = "Hello World";
        Scanner scanner = new Scanner(source);
        scanner.close();
        System.out.println(scanner.hasNext());

    }
}

Output:

Exception in thread "main" java.lang.IllegalStateException: Scanner closed at java.base/java.util.Scanner.ensureOpen(Scanner.java:1150) at java.base/java.util.Scanner.hasNext(Scanner.java:1439)


No comments:

Post a Comment