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Simplify Coding with Java Utility Classes: Implementation and Usage

Java is one of the most popular programming languages used to develop a wide range of software applications. Utility classes in Java, also known as helper classes, play a crucial role in software development by providing commonly used methods that help to simplify coding and increase efficiency.

These classes usually contain a collection of static methods that perform specific tasks, such as manipulation of strings or mathematical calculations.to Utility Classes

Java utility classes, as mentioned, are collections of static methods that provide commonly used functionalities in a program. These classes are also referred to as helper classes because they assist in performing tasks that would otherwise require more complex coding or multiple steps.

Utility classes are stateless, meaning they do not maintain any state information, so their methods can only operate on the parameters passed to them.

Syntax and Restrictions of Utility Classes

A Java utility class contains only static methods, and its constructor is private, which means that it cannot be instantiated. The private constructor prevents the creation of objects from the class, which ensures that all the methods inside the class can be accessed without any instance of the class.

To declare a Java utility class, use the final keyword to prevent subclassing, since utility classes are not meant to be extended. Also, all methods in utility classes should be declared public to allow access from other classes.

Examples of Java Utility Classes

Utility classes are fundamental in Java programming, and they exist in numerous libraries and frameworks. Some of the famous Java utility classes include the following:

Apache StringUtils: This class provides methods for manipulating strings, such as string concatenation and trimming.

CollectionUtils: This is an Apache utility Java class that contains methods for manipulating collections, such as copying and filtering. java.lang.Math: Math class provides mathematical functionalities such as rounding off numbers, performing arithmetic operations, and calculating trigonometric functions.

Creating and Using Utility Classes in Java

Designing Methods in Utility Class

The methods of a utility class should be designed to perform specific, well-defined tasks that can be reused in multiple parts of the program. Static methods of the class do not have a reference to an object, thus eliminating the need for instantiating an object.

Therefore, utility classes should only contain static methods or, in rare cases, final methods. The static keyword in methods ensures that the method is associated with the class and not with the object.

For example, the Math class contains static methods that perform calculations and returns the result without creating any objects.

Creating a Private Constructor in Utility Classes

Creating a private constructor in a utility class prevents the creation of objects from the class. This is because a utility class is only meant to contain methods that provide functionality and not store data.

Additionally, a private constructor eliminates the need for subclassing since the original class contains the necessary methods.

Examples of Methods in a Utility Class

Math Class: This class contains various mathematical methods, including adding, subtracting, multiplying, and dividing, which can be used in any program. Math.round(): This static method in the Math class rounds off floating-point numbers to the nearest whole number.

Float.sum(): This method in the Float class takes in two float numbers as input, adds them, and returns the result as a float number. To conclude, utility classes are essential in Java programming as they simplify coding, increase efficiency, and provide commonly used functionalities.

When designing utility classes, consider creating only static methods and a private constructor to prevent object creation. Examples of utility classes in Java include the Math class, StringUtils, and CollectionUtils, which can be easily used in any program.

As you build your Java programs, utilize utility classes to simplify complex tasks, save time, and make your code more efficient. Using utility classes in Java allows programmers to simplify coding, improve code efficiency, and reuse commonly used functionalities across various parts of a program.

In this article, we will focus on the implementation and output of a sample utility class, highlighting how to use it in a Java program.

Description of Sample Utility Class

To illustrate the implementation and output of a Java utility class, we will use an example called UtilityClassExample. This class will contain two static methods: add, which returns the sum of two integers, and multiply, which returns the product of two integers.

The UtilityClassExample is declared with the final keyword, preventing subclassing, and a private constructor that controls instantiation. The class and methods are declared public, allowing access from other classes in the program.

Here’s the code for UtilityClassExample:


public final class UtilityClassExample {

private UtilityClassExample() {

// private constructor to prevent instantiation


public static int add(int num1, int num2) {

return num1 + num2;


public static int multiply(int num1, int num2) {

return num1 * num2;




Example of How to Use a Utility Class

To use the UtilityClassExample in a Java program, we first need to import it into our program. Here’s an example program demonstrating how to use the add and multiply methods of the UtilityClassExample:


import java.util.Scanner;

public class Main {

public static void main(String[] args) {

int num1, num2;

Scanner scanner = new Scanner(System.in);

System.out.print(“Enter the first number: “);

num1 = scanner.nextInt();

System.out.print(“Enter the second number: “);

num2 = scanner.nextInt();

int result1 = UtilityClassExample.add(num1, num2);

int result2 = UtilityClassExample.multiply(num1, num2);

System.out.println(num1 + ” + ” + num2 + ” = ” + result1);

System.out.println(num1 + ” * ” + num2 + ” = ” + result2);




In the main method of the above program, we first prompt the user to enter two integers, which are stored in the variables num1 and num2, respectively.

We then call the add and multiply methods of the UtilityClassExample using the class name followed by the dot operator and passing the two integers as parameters. The values returned by the add and multiply methods are stored in the variables result1 and result2, respectively.

We then use the System.out.print method to print the output to the console, showing the values of num1, num2, result1 and result2, and the operation performed. When we run the program and enter 5 and 2 as input, we will get the following output:


Enter the first number: 5

Enter the second number: 2

5 + 2 = 7

5 * 2 = 10


The program successfully used the add and multiply methods of the UtilityClassExample to calculate the sum and product of the two user-provided integers.

In conclusion, a Java utility class contains static methods that provide commonly used functionalities in a program. In this article, we demonstrated the implementation and output of a sample utility class called UtilityClassExample, which contained the add and multiply methods.

We also showed how to use the class in a Java program using the main method, calling the class methods and printing the output. Utility classes are essential tools for Java programmers as they help simplify coding, increase efficiency, and promote code reuse.

In conclusion, Java utility classes are essential in software development as they facilitate code efficiency, simplify coding and promote code reuse. Utility classes contain static methods that provide commonly used functionalities in a program.

We demonstrated the implementation and output of a UtilityClassExample, highlighting how to use it in a Java program. It is crucial to design methods in utility classes to perform specific, well-defined tasks, with a private constructor to prevent object creation.

The use of utility classes saves time and creates cleaner, more efficient code. As a Java programmer, utilize utility classes to promote smoother workflow, easier debugging, and increased productivity.

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