Java:
Finding the length of a string

How to:

Java strings have a length() method. Call it, and you get the character count. Easy.

public class StringLengthExample {
    public static void main(String[] args) {
        String greeting = "Hello, World!";
        int length = greeting.length();

        System.out.println("The length of the string is: " + length);
        // Output: The length of the string is: 13
    }
}

Deep Dive

The length() method dates back to the earliest Java versions, making it a long-standing part of the String class. It’s simple but essential. Internally, a String in Java is backed by a character array, with the length() method returning the size of this array. Crucially, Java strings are immutable, so once created, the length doesn’t change, making the method quick and reliable.

Alternatives? Well, other than rolling your own function to count characters (unnecessary and non-performant), not really. Keep in mind that length() returns the number of char units, not necessarily code points. For Unicode characters that don’t fit in the standard 16-bit char size, consider using codePointCount() if you need to account for supplementary characters.

See Also

Dive deeper or explore related topics:

• Java String Documentation
• Java Character Class Docs for understanding more on Unicode, characters, and code points.
• Oracle’s Java Tutorials for a broader understanding of strings in Java.