Table of contents
1.
Introduction 
2.
How to find the Java string length?
3.
String length() in Java
3.1.
Syntax 
3.2.
Parameters 
3.3.
Return Value 
3.4.
Internal Implementation 
4.
Java String Length() Examples 
4.1.
Example 1: 
4.2.
Java
4.3.
Example 2: 
4.4.
Java
4.5.
Example 3: 
4.6.
Java
5.
Java String length() Companion Methods
6.
String length Method Vs Property
7.
Frequently Asked Questions
7.1.
What is string length?
7.2.
What is the size of the string type in Java?
7.3.
How do you find the size of a string?
7.4.
List the features of the Java Programming language? 
7.5.
What are the different memory allocations in java?  
7.6.
Will the program run if we write a public static void main?   
7.7.
Why isn't Java fully object-oriented? 
8.
Conclusion 
Last Updated: Jul 8, 2024
Easy

Java String Length() Method

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Introduction 

In Java programming, the length() method is a fundamental feature of the String class, providing a straightforward way to determine the number of characters in a string. This method returns an integer representing the number of Unicode code units (characters) present in the string, making it essential for tasks like validation, manipulation, and boundary checks within text processing applications. This blog explores the Java String Length() Method.

Java String Length() Method

How to find the Java string length?

To find the length of a Java string, use the length() method provided by the String class. This method returns an integer representing the number of characters in the string. For example:

String str = "Hello, World!";
int length = str.length(); // length will be 13

The length() method is efficient and counts all characters, including spaces and special characters, in the string.

String length() in Java

This Java method returns the length of the string. The length of the string will be equal to the number of 16-bit Unicode characters in the string. 

Syntax 

public int length()

Parameters 

None. There are no parameters passed into the string length() function in java. 

Return Value 

Returns the int value representing the length of the string. 

Internal Implementation 

public int length() {  
	return value.length;  
}  

 

The characters are stored in a char[] array within the String class. The array's length variable determines the total number of elements in the array. The length variable cannot be accessible to the outside world because the Java String class internally utilizes this char[] array. As a result, the length() method was created by Java developers to reveal the value of the length variable. The length() function is similar to the getter() method in that it returns the value of the class field to the user. The length() method returns the value of the length variable, as shown in the internal implementation.

Must Read: Java System Out Println

Java String Length() Examples 

Example 1: 

  • Java

Java

import java.io.*;

public class Example1 {

   public static void main(String args[]) {
       String Str1 = new String("Welcome to CodingNinjas.com");
       String Str2 = new String("CodingNinjas");

       System.out.print("String Length :");
       System.out.println(Str1.length());

       System.out.print("String Length :");
       System.out.println(Str2.length());
   }
}
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Output:

String Length:27
String Length:12

Example 2: 

  • Java

Java

public class Example2 {
   public static void main(String[] args) {
       String str = "CodingNinjas";
       if (str.length() == 0) {
           System.out.println("String is empty");
       } else {
           System.out.println("String is not empty and length is: " + str.length());
       }
   }
}
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Output: 

String is not empty and the length is: 12

Example 3: 

  • Java

Java

public class Example3 {
   public static void main(String[] args) {
       String txt = "Learning Coding means Coding Ninjas";
       System.out.println(txt.length());
   }
}
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Output:

35 


Must Read: String Args in Java

Java String length() Companion Methods

String Method Method Function
length() Returns the number of characters in the string.
isEmpty() Checks if the string length is zero (length() == 0).
codePointCount() Returns the number of Unicode code points in the specified range.
getBytes(Charset charset) Converts the string into a byte array using the specified charset and returns the array's length.

String length Method Vs Property

Aspect Method Property
Access Invoked using a method call (str.length()). Accessed directly (str.length), but not available in Java.
Definition Method is a function associated with an object or class (length()). Property refers to a characteristic of an object (length) in languages such as JavaScript.

Frequently Asked Questions

What is string length?

String length refers to the number of characters, including spaces and special characters, present in a string.

What is the size of the string type in Java?

In Java, the size of the String type depends on the number of characters it contains, each character typically occupying 2 bytes of memory.

How do you find the size of a string?

To find the size (length) of a string in Java, use the length() method provided by the String class, which returns the number of characters in the string.

List the features of the Java Programming language? 

Java is a language that is thought to be simple to learn. There is a catch to understanding one of OOP Java's essential concepts.

  • Java offers a security feature that aids in developing a virus-free and tamper-free system for users
  • Object-Oriented Programming Language (OOP): OOP stands for Object-Oriented Programming language. Everything in Java is considered an object, according to OOP.
  • Platform-Independent Bytecode: Java is compiled into platform-independent bytecode rather than a platform-specific processor. The Virtual Machine on which the platform operates interprets this code.
    Know Why is Java Platform Independent here.

What are the different memory allocations in java?  

Different memory allocations in Java are: 

  • Heap Memory
  • Class Memory
  • Stack Memory
  • Native Method Stack Memory
  • Program Counter-Memory

Will the program run if we write a public static void main?   

Yes, if written correctly, the application will run successfully. Because there is no precise rule for specifying the order of specifiers in Java.  

Why isn't Java fully object-oriented? 

Java still uses eight or more primitive data types like int, float, double, etc. Java is not considered a fully object-oriented programming language.

Conclusion 

In this article, we discussed the java string length() method. I hope you understand the syntax and use of string length(). 

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Also check out - String Interview Questions In Java

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