Java String copyValueOf() Method

The String.copyValueOf() method in Java is used to create a new string that contains the characters from a specified character array. 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. copyValueOf Method Syntax
3. Examples
   • Creating a String from a Character Array
   • Creating a Substring from a Character Array
4. Conclusion

Introduction

The String.copyValueOf() method is a static method in the String class. It allows you to create a new string that contains the characters from a specified character array. This method is particularly useful when you need to convert a character array to a string.

copyValueOf Method Syntax

The copyValueOf method has two common variations:

1. Creating a string from the entire character array:

public static String copyValueOf(char[] data)

2. Creating a substring from a portion of the character array:

public static String copyValueOf(char[] data, int offset, int count)

• data: The character array.
• offset: The starting index in the character array.
• count: The number of characters to include in the new string.

Examples

Creating a String from a Character Array

The copyValueOf method can be used to create a new string that contains the characters from an entire character array.

Example

public class CopyValueOfExample {
    public static void main(String[] args) {
        char[] charArray = {'H', 'e', 'l', 'l', 'o'};

        String str = String.copyValueOf(charArray);

        System.out.println("Character array: " + java.util.Arrays.toString(charArray));
        System.out.println("String: " + str);
    }
}

Output:

Character array: [H, e, l, l, o]
String: Hello

Creating a Substring from a Character Array

The copyValueOf method can also be used to create a new string that contains a substring from a portion of the character array.

Example

public class CopyValueOfExample {
    public static void main(String[] args) {
        char[] charArray = {'H', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l', 'd'};

        String str = String.copyValueOf(charArray, 6, 5);

        System.out.println("Character array: " + java.util.Arrays.toString(charArray));
        System.out.println("Substring: " + str);
    }
}

Output:

Character array: [H, e, l, l, o,  , W, o, r, l, d]
Substring: World

Conclusion

The String.copyValueOf() method in Java provides a convenient way to create a new string from a character array or a portion of a character array. By understanding how to use this method, you can efficiently convert character arrays to strings in your Java applications. Whether you are creating a string from the entire character array or a substring from a portion of the array, the copyValueOf method offers a reliable solution for these tasks.