Do you know what methods in Java are? Methods are useful functions that belong to a class, and understanding them is crucial for Java developers to develop robust applications. This guide includes a detailed explanation of everything one should know about these Java methods. It begins with a basic introduction and explains all aspects, including its features, types, key components, and syntax, as well as the process of creating and calling them.
Learning about Java methods can be a game-changer for anyone aiming to become a proficient Java developer. The programming language doesn't demand writing long, complex code for every task, saving valuable time that developers can spend on more critical challenges. Learning this concept not only boosts productivity but also opens doors to exciting career opportunities. In fact, skilled Java developers earn an impressive average salary of $91,000 per year, making it a smart investment in your future.
Methods in Java are blocks of code that perform specific tasks and can be called to execute when needed. A method, also known as a function, is designed to perform specific tasks, improve code reusability, and reduce redundancy. Developers just have to create one and then they can call it in different codes. Its reusability improves the performance and efficiency of the programmer.
Each of them belongs to a special class. It is also referred to as a function that exposes a particular behavior of objects. There are many features of methods in Java. Let's explore some of them.
Explore all Programming Courses by igmGuru to become a successful programmer.
The use of methods in Java is one of the most contributing factors to its success. This gives many features to programmers. In fact, these are the foundations of Java programming. Let us dive into these features -
Code reusability is one of the most important perks of using methods. Individuals can use them again and again in the same or different codes after creating one. This reduces the chances of errors in concise code. It is also easier to manage these types of programs. Here is an instance of code reusability that can calculate the square of any given number.
public class ReusableMethods { public static int square(int numb) { return numb * numb; } public static void main(String[] args) { int res1 = square(5); int res2 = square(10); System.out.println("Square of 6: " + res1); System.out.println("Square of 9: " + res2); } } |
Code organization is another feature of these methods. It divides a long code into smaller sections that are easy to maintain and comprehend. It is also better for teamwork and readability. Here is an instance of this feature that separates the welcome and farewell messages.
public class CodeOrganization { public static void displayWelcomeMessage() { System.out.println("Welcome to Java's class"); } public static void displayFarewellMessage() { System.out.println("Thanks for training Java with us"); } public static void main(String[] args) { displayWelcomeMessage(); displayFarewellMessage(); } } |
It is easy to read and maintain the methods in Java programming. Individuals can encapsulate special functionalities within a method by assigning them meaningful names. This approach makes it easy to understand the function of the code. It is also possible to correct bugs without affecting any parts of a program with these. Here is an instance of these types of methods -
public class Readability { public static double calculateRectangleArea(double len, double wid) { return len * wid; } public static void main(String[] args) { double len = 9.0; double wid = 2.0; double area = calculateRectangleArea(len, wid); System.out.println("Rectangle area is: " + area); } } |
Explore top Java Interview Questions to ace your interview.
There are many key components of methods in Java as shown below. Each of them is focused on declaring a particular element or performing a task in the code.
1. Access Modifier - It defines the access level of a method like private, public, protected or default.
2. Return Type - It decides the type of return value or gives void if no value is returned.
3. Method Name - It is the Java naming conventions that start with a lowercase and use camelcase for many words.
4. Method Parameters - It is a list of input values. These are only used when parameters are needed.
5. Exception List - These are the exceptions that the method might throw.
6. Method Header & Body - It contains the logic of the code that has to be executed.
Related Article - Golang vs Java: What Should You Choose?
Types of methods in Java are typically classified into two types including predefined and user-defined. Both of these are suitable to use in different instances.
The predefined methods are the ones that are already available in the Java library. These can be called when needed without needing to define them. There are many predefined methods, including sqrt(), max(), length() and print(). Each of them is available within their respective classes. Here is an instance of using these methods.
public class Example { public static void main(String args[]) { System.out.println("The Square root is: " + Math.sqrt(25)); // Added the missing quote } } |
User-defined methods are defined by the user themselves. Users can modify and tweak them according to the situation and requirements. Below is an example of using this type of method.
public class Example { // Creating a method public int subNumbers(int x, int y) { int subtract = x - y; // Returning the value return subtract; } public static void main(String[] args) { int num1 = 57; int num2 = 22; // Creating an object of Example class Example obj = new Example(); // Calling the method int outcome = obj.subNumbers(num1, num2); System.out.println("Outcome is: " + outcome); } } |
Also Read: Java Projects
Learning how to create methods in Java requires understanding its syntax, defining processes, and calling methods. These are the steps of building a program. One should start by creating the method signature that includes the method name, return type, and parameters. Then comes the main task, which is writing the main body. The body contains the logic of the code. Let's understand it with some instances.
There are different syntaxes to create a method signature. We are using the following syntax -
public <return type> |
We are using an abstract method in Java with this syntax that takes two parameters and returns a single integer -
abstract class MyClass { public abstract int add(int a, int b); // Abstract method public static void main(String args[]) { // You can't directly instantiate an abstract class // MyClass instance = new MyClass(); // This will cause a compile-time error // You need to create a concrete subclass that implements the abstract method MyClass instance = new MySubclass(); // Example: Using a subclass (see below) int result = instance.add(12, 3); System.out.println(result); } } // Concrete subclass that implements the abstract method class MySubclass extends MyClass { @Override public int add(int a, int b) { int result = 0; result = a + b; return result; } } |
The above instance is the perfect one to understand how to define methods in a class. The first row on this program is in the method signature. The public keyword shows that we have called this method from outside of the class.
Then the return type is an int, which means it will return an integer value. Our method name is add, and the parameters are integer a and integer b. The logic of the body adds the two parameters and returns the result.
It is possible to call a method from anywhere in the program with the following syntax -
<object reference>. |
For instance, the code given below calls the add method with the parameters 12 and 3 -
int result = myClass.add(12, 3); |
public void printMessage() { System.out.println("Hello, world!"); } |
class MyClass { public void printMessage() { System.out.println("Hello, world!"); } } public class Main { public static void main(String[] args) { MyClass object = new MyClass(); object.printMessage(); // prints "Hello, world!" to the screen } } |
// Java Program to Implement // Method Overloading import java.io.*; class MethodOverloadingEx { static int add(int a, int b) { return a + b; } static int add(int a, int b, int c) { return a + b + c; } // Main Function public static void main(String args[]) { System.out.println("add() with 2 parameters"); // Calling function with 2 parameters System.out.println(add(4, 6)); System.out.println("add() with 3 parameters"); // Calling function with 3 Parameters System.out.println(add(4, 6, 7)); } } |
import java.io.*; // Base Class class Animal { void eat() { System.out.println("eat() method of base class"); System.out.println("Animal is eating."); } } // Derived Class class Dog extends Animal { @Override void eat() { System.out.println("eat() method of derived class"); System.out.println("Dog is eating."); }
// Method to call the base class method void eatAsAnimal() { super.eat(); } } // Driver Class class MethodOverridingEx { // Main Function public static void main(String args[]) { Dog d1 = new Dog(); Animal a1 = new Animal(); // Calls the eat() method of Dog class d1.eat(); // Calls the eat() method of Animal class a1.eat(); // Polymorphism: Animal reference pointing to Dog object Animal animal = new Dog();
// Calls the eat() method of Dog class animal.eat();
// To call the base class method, you need to use a Dog reference ((Dog) animal).eatAsAnimal(); } } |
Also Explore: Python Tutorial
Programming in Java can be very complicated when working on difficult tasks. The use of methods in Java promotes modularity, reusability and abstraction that ultimately simplify complicated tasks. Mastering methods is important for any Java developer who wants to seek proficiency and code excellence. It is the best solution to create codes with minimum errors and maximum efficiency.
The entry point for executing a Java program is considered the main method. It is the first method that is called when a Java class is executed. The syntax of this method is public static void main(String[] args).
It is possible to use more than one main method in Java with different parameter lists. But it will only call the method that has the signature syntax when starting your program.
The void is a keyword in Java programming language. It specifies that the method can not return any value. It is also referred to as a return type that shows the method performs a task but does not give any result.
Claude Fable 5 and Mythos 5: Anthropic's Most Powerful AI Model
June 11th, 2026
