How to Read Multiple Word Strings Using Java's Scanner Class?

How can I read multiple word strings using the java.util.Scanner class in Java?

Scanner scanner = new Scanner(System.in);
System.out.print("Enter multiple words: ");
while(scanner.hasNext()) {
    String word = scanner.next();
    System.out.println(word);
}

In Java, the `Scanner` class facilitates reading input from various sources, including user input from the console. When it comes to reading multiple word strings, `Scanner` can be leveraged to split input based on whitespace by using methods like `next()` or `nextLine()`. This guide will demonstrate how to do it effectively.

import java.util.Scanner;

public class ReadMultipleWords {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter multiple words (type 'exit' to quit): ");

        while(scanner.hasNextLine()) {
            String input = scanner.nextLine();
            if(input.equalsIgnoreCase("exit")) {
                break;
            }
            System.out.println("You entered: " + input);
        }
        scanner.close();
    }
}

Causes

• Not handling the newline character when reading input.
• Using `next()` instead of `nextLine()` when you need to capture the entire line including spaces.

Solutions

• Use the `nextLine()` method to read an entire line which may contain multiple words separated by spaces.
• Utilize a while loop combined with `hasNext()` to continually capture input until the user chooses to stop.

Mistake: Using `next()` when expecting input with spaces, which only retrieves a single word.

Solution: Use `nextLine()` to capture the entire line, including spaces.

Mistake: Failing to close the scanner object, which can lead to resource leaks.

Solution: Always close the scanner with `scanner.close()` when done.