Java String strip() Method

The String.strip() method in Java is used to remove leading and trailing whitespace from a string. This guide will cover the method's usage, explain how it works, and provide examples to demonstrate its functionality.

Table of Contents

1. Introduction
2. strip Method Syntax
3. Examples
   • Removing Leading and Trailing Whitespace
   • Comparison with trim()
   • Using stripLeading() and stripTrailing()
4. Conclusion

Introduction

The String.strip() method is a member of the String class in Java, introduced in Java 11. It allows you to remove leading and trailing whitespace from a string, similar to the trim() method but with more precise Unicode whitespace handling.

strip Method Syntax

The syntax for the strip method is as follows:

public String strip()

Examples

Removing Leading and Trailing Whitespace

The strip method can be used to remove leading and trailing whitespace from a string.

Example

public class StripExample {
    public static void main(String[] args) {
        String message = "   Hello, World!   ";

        String strippedMessage = message.strip();

        System.out.println("Original message: '" + message + "'");
        System.out.println("Stripped message: '" + strippedMessage + "'");
    }
}

Output:

Original message: '   Hello, World!   '
Stripped message: 'Hello, World!'

Comparison with trim()

The strip method handles Unicode whitespace more precisely compared to the trim() method, which only removes ASCII whitespace.

Example

public class StripExample {
    public static void main(String[] args) {
        String message = "\u2000\u2000Hello, World!\u2000\u2000";  // Unicode whitespace

        String trimmedMessage = message.trim();
        String strippedMessage = message.strip();

        System.out.println("Original message: '" + message + "'");
        System.out.println("Trimmed message: '" + trimmedMessage + "'");
        System.out.println("Stripped message: '" + strippedMessage + "'");
    }
}

Output:

Original message: '  Hello, World!  '
Trimmed message: '  Hello, World!  '
Stripped message: 'Hello, World!'

Using stripLeading() and stripTrailing()

Java 11 also introduced the stripLeading() and stripTrailing() methods to remove leading or trailing whitespace respectively.

Example

public class StripExample {
    public static void main(String[] args) {
        String message = "   Hello, World!   ";

        String leadingStrippedMessage = message.stripLeading();
        String trailingStrippedMessage = message.stripTrailing();

        System.out.println("Original message: '" + message + "'");
        System.out.println("Leading stripped message: '" + leadingStrippedMessage + "'");
        System.out.println("Trailing stripped message: '" + trailingStrippedMessage + "'");
    }
}

Output:

Original message: '   Hello, World!   '
Leading stripped message: 'Hello, World!   '
Trailing stripped message: '   Hello, World!'

Conclusion

The String.strip() method in Java is used for removing leading and trailing whitespace from a string. By understanding how to use this method, you can efficiently clean and format strings in your Java applications. Whether you are comparing it with the trim() method, or using stripLeading() and stripTrailing(), the strip method provides a reliable solution for handling whitespace.