Java String endsWith() Method

The String.endsWith() method in Java is used to check if a string ends with a specified suffix.

Table of Contents

1. Introduction
2. endsWith Method Syntax
3. Examples
   • Basic Usage
   • Case Sensitivity
   • Using endsWith with Special Characters
   • Real-World Use Case
4. Conclusion

Introduction

The String.endsWith() method is a member of the String class in Java. It allows you to determine if a string ends with a specified sequence of characters (suffix). This is particularly useful for validation and filtering purposes.

endsWith() Method Syntax

The syntax for the endsWith method is as follows:

public boolean endsWith(String suffix)

• suffix: The suffix to check.

Examples

Basic Usage

The endsWith method can be used to check if a string ends with a specified suffix.

Example

public class EndsWithExample {
    public static void main(String[] args) {
        String str = "Welcome to Java";
        boolean result = str.endsWith("Java");
        System.out.println("Ends with 'Java': " + result);
    }
}

Output:

Ends with 'Java': true

Case Sensitivity

The endsWith method is case-sensitive, meaning it will only return true if the exact suffix, including case, is found.

Example

public class CaseSensitiveExample {
    public static void main(String[] args) {
        String str = "Welcome to Java";
        boolean result1 = str.endsWith("java");
        boolean result2 = str.endsWith("Java");
        System.out.println("Ends with 'java': " + result1);
        System.out.println("Ends with 'Java': " + result2);
    }
}

Output:

Ends with 'java': false
Ends with 'Java': true

Using endsWith with Special Characters

The endsWith method can also be used with strings containing special characters.

Example

public class SpecialCharactersExample {
    public static void main(String[] args) {
        String str = "Welcome to Java @2021!";
        boolean result = str.endsWith("@2021!");
        System.out.println("Ends with '@2021!': " + result);
    }
}

Output:

Ends with '@2021!': true

Real-World Use Case

Example: Checking File Extensions

One common use case for endsWith is checking file extensions, such as validating if a file is an image based on its extension.

public class FileExtensionExample {
    public static void main(String[] args) {
        String fileName1 = "photo.jpg";
        String fileName2 = "document.pdf";

        if (fileName1.endsWith(".jpg") || fileName1.endsWith(".png")) {
            System.out.println(fileName1 + " is an image file.");
        } else {
            System.out.println(fileName1 + " is not an image file.");
        }

        if (fileName2.endsWith(".jpg") || fileName2.endsWith(".png")) {
            System.out.println(fileName2 + " is an image file.");
        } else {
            System.out.println(fileName2 + " is not an image file.");
        }
    }
}

Output:

photo.jpg is an image file.
document.pdf is not an image file.

In this example, the endsWith method is used to check if the filenames have the correct image file extensions (e.g., .jpg or .png).

Conclusion

The String.endsWith() method in Java is a simple yet powerful tool for checking if a string ends with a specified suffix. It is case-sensitive and works with strings containing special characters. This method is particularly useful for validation and filtering strings in various applications. By understanding and utilizing the endsWith method, you can efficiently manage string suffix checks in your Java programs.