How to Get the Length of a String in Java - onlyxcodes

Tuesday 2 July 2024

How to Get the Length of a String in Java

Hello, We will learn how to get a string's length in Java in this tutorial.


Finding a string's length has been frequently an essential task when working with strings in Java. The total amount of characters in a string, including spaces and special characters, is referred to as its length.


Java offers a simple way to accomplish this using the String class. This post covers several methods for determining a string's length in Java, with examples for every method.


how to get the length of a string in java

Table Content

1. Introduction to Strings in Java

2. Using the length() Method

3. Working with Unicode Characters

4. Handling Null Strings

5. Practical Examples

6. Conclusion


1. Introduction to Strings in Java

Strings in Java are instances of the String class, a component java .lang package. Strings cannot alter their values after they are formed because they are immutable. Java has many methods within the String class for editing strings.


2. Using the length() Method

Using the length() method that the String class provides is the most popular and straightforward way to find the length of a string in Java. The number of characters in the string is returned by this method.


Syntax:


public int length()

Example


Here is a simple example demonstrating how to use the length() method:


In this example, the string "Hello, World!" contains 13 characters, so the length() method returns 13.


public class Test 
{
    public static void main(String[] args) 
	{
        String str = "Hello, World!";
        int length = str.length();
        System.out.println("The length of the string is: " + length);
    }
}

Output:


The length of the string is: 13

3. Working with Unicode Characters

You may work with an extensive range of characters from other languages and symbols thanks to Java's String class, which manages Unicode characters. It's essential to realize that, because some Unicode characters may be represented by a pair of char values (substitute pairs), the length () method counts the number of char values in the string rather than the total number of Unicode characters.


Example with Unicode Characters


In this example, the emoji "😊" is represented by a surrogate pair, so the length() method returns 4.


public class Test 
{
    public static void main(String[] args) 
	{
        String str = "😊";
        int length = str.length();
        System.out.println("The length of the string is: " + length);
    }
}

Output:


The length of the string is: 4

4. Handling Null Strings

Null values are something you may run into while working with strings. A NullPointerException will be raised if the length () method is attempted to be called on a null string. Always make sure the string is null before using the length () method to prevent this.


Example with Null Check


In this example, the program safely handles the null string by checking its value before attempting to call the length() method.


public class Test 
{
    public static void main(String[] args) 
	{
        String str = null;
        if (str != null) 
		{
            int length = str.length();
            System.out.println("The length of the string is: " + length);
        } 
		else 
		{
            System.out.println("The string is null.");
        }
    }
}

Output:


The string is null.

5. Practical Examples

Example 1: Counting Characters in User Input


This example demonstrates how to count the number of characters in a user's input string.


import java.util.Scanner;

public class Test
{
    public static void main(String[] args) 
	{
        Scanner scanner = new Scanner(System.in);
        System.out.println("Enter a string: ");
        String input = scanner.nextLine();
        int length = input.length();
        System.out.println("The length of the input string is: " + length);
    }
}

Output:


Enter a string: 
Java programming
The length of the input string is: 16

Example 2: Finding Length of an Array of Strings


This example shows how to find the length of each string in an array of strings.


public class Test
{
    public static void main(String[] args) 
	{
        String[] strings = {"Java", "Python", "C++", "JavaScript"};
        for (String str : strings) {
            System.out.println("The length of \"" + str + "\" is: " + str.length());
        }
    }
}

Output:


The length of "Java" is: 4
The length of "Python" is: 6
The length of "C++" is: 3
The length of "JavaScript" is: 10

6. Conclusion

Using the String class's length () function, figuring out a string's length in Java is an easy operation. The number of characters in the string, including spaces and special characters, is counted using this approach. In order to prevent exceptions, it's important to handle null strings and comprehend how Unicode characters may impact the length calculation.

You can handle strings in Java with confidence once you understand this basic procedure, which opens the door to more difficult string-handling jobs.

No comments:

Post a Comment

Post Bottom Ad