Java Methods - Syntax, Types and Complete Examples

⏱️ 10 min read • Beginner Level • Lesson 33

A method in Java is a block of code that performs a specific task. Methods help you write reusable, organized, and easy-to-maintain programs.

Before learning methods, you should understand Java Program Structure, Java Variables, and Java Data Types. After this lesson, continue with Java Method Parameters.

What is a Method in Java?

A method is a group of statements written together to perform a particular operation. Instead of writing the same code again and again, you can define a method once and call it whenever required.

Why Use Methods in Java?

Real-World Example of Methods

Methods are used everywhere in real applications. For example, an online shopping website may use separate methods for:

• Calculating the total bill
• Applying discounts
• Processing payments
• Sending confirmation emails

Instead of writing all logic inside the main() method, developers divide the program into smaller reusable methods.

Syntax of Method in Java

The general syntax of a Java method is:

accessModifier returnType methodName(parameters) {
    // method body
}

Parts of a Java Method

Default Access Method Example

If a method does not use public, private, or protected, it has default access. This means it can be accessed only by classes in the same package.

class DefaultAccessMethodExample {

    void showMessage() {
        System.out.println("This method has default access.");
    }

    public static void main(String[] args) {
        DefaultAccessMethodExample obj = new DefaultAccessMethodExample();
        obj.showMessage();
    }
}

Output:

This method has default access.

How to Call a Method in Java

A method runs only when it is called. Static methods can be called directly from another static method in the same class, while instance methods need an object.

public class CallMethodExample {
    static void greet() {
        System.out.println("Hello Java");
    }

    public static void main(String[] args) {
        greet();
    }
}

Output:

Hello Java

Predefined Methods in Java

Predefined methods are already available in Java libraries. You can use them without writing their body. Examples include System.out.println(), Math.sqrt(), and String.length().

public class PredefinedMethodExample {
    public static void main(String[] args) {
        System.out.println("Java Methods");
        System.out.println(Math.sqrt(25));
        System.out.println("ProwessApps".length());
    }
}

Output:

Java Methods
5.0
11

User-Defined Methods in Java

User-defined methods are methods created by the programmer to perform specific tasks.

public class UserDefinedMethodExample {
    static void showMessage() {
        System.out.println("This is a user-defined method.");
    }

    public static void main(String[] args) {
        showMessage();
    }
}

Output:

This is a user-defined method.

void Method in Java

A void method performs a task but does not return any value.

public class VoidMethodExample {
    static void printWelcome() {
        System.out.println("Welcome to Java methods.");
    }

    public static void main(String[] args) {
        printWelcome();
    }
}

Output:

Welcome to Java methods.

Return Type Method in Java

A return type method performs a task and sends a value back to the caller using the return statement.

public class ReturnMethodExample {
    static int square() {
        return 5 * 5;
    }

    public static void main(String[] args) {
        int result = square();
        System.out.println("Square: " + result);
    }
}

Output:

Square: 25

Parameterized Method in Java

A parameterized method accepts one or more input values through parameters.

public class ParameterizedMethodExample {
    static void showStudent(String name, int age) {
        System.out.println("Name: " + name);
        System.out.println("Age: " + age);
    }

    public static void main(String[] args) {
        showStudent("Ayan", 20);
    }
}

Output:

Name: Ayan
Age: 20

No-Argument Method in Java

A no-argument method does not accept any parameters.

public class NoArgumentMethodExample {
    static void displayDateMessage() {
        System.out.println("Today is a good day to learn Java.");
    }

    public static void main(String[] args) {
        displayDateMessage();
    }
}

Output:

Today is a good day to learn Java.

Static Method in Java

A static method belongs to the class. It can be called without creating an object.

public class StaticMethodExample {
    static void showMessage() {
        System.out.println("Static method called");
    }

    public static void main(String[] args) {
        StaticMethodExample.showMessage();
    }
}

Output:

Static method called

Instance Method in Java

An instance method belongs to an object. You must create an object to call an instance method.

public class InstanceMethodExample {
    void showMessage() {
        System.out.println("Instance method called");
    }

    public static void main(String[] args) {
        InstanceMethodExample obj = new InstanceMethodExample();
        obj.showMessage();
    }
}

Output:

Instance method called

Recursive Method in Java

A recursive method is a method that calls itself. Recursion is useful for problems that can be divided into smaller similar problems.

public class RecursiveMethodExample {
    static int factorial(int number) {
        if (number == 1) {
            return 1;
        }
        return number * factorial(number - 1);
    }

    public static void main(String[] args) {
        System.out.println("Factorial: " + factorial(5));
    }
}

Output:

Factorial: 120

Getter and Setter Methods in Java

Getter and setter methods are commonly used to read and update private variables. Getter methods are also called accessor methods, and setter methods are also called mutator methods.

class Student {
    private String name;

    public void setName(String studentName) {
        name = studentName;
    }

    public String getName() {
        return name;
    }
}

public class GetterSetterExample {
    public static void main(String[] args) {
        Student student = new Student();
        student.setName("Ayan");
        System.out.println(student.getName());
    }
}

Output:

Ayan

Complete Example of Java Methods

This example uses static method, instance method, void method, return method, and parameterized method together.

public class JavaMethodsExample {

    static void welcomeMessage() {
        System.out.println("Welcome to Java Methods");
    }

    static int addNumbers(int a, int b) {
        return a + b;
    }

    void displayResult(int result) {
        System.out.println("Result: " + result);
    }

    public static void main(String[] args) {
        welcomeMessage();

        int sum = addNumbers(10, 20);

        JavaMethodsExample obj = new JavaMethodsExample();
        obj.displayResult(sum);
    }
}

Output:

Welcome to Java Methods
Result: 30

Types of Methods in Java - Quick Revision

Common Mistakes with Java Methods

Frequently Asked Questions

🧠 Test your understanding with a quick quiz

public class Test {
    static int add(int a, int b) {
        return a + b;
    }

    public static void main(String[] args) {
        System.out.println(add(10, 20));
    }
}

public class Test {
    static void greet() {
        System.out.println("Hello Java");
    }

    public static void main(String[] args) {
        greet();
    }
}

public class Test {
    static void show(String name) {
        System.out.println(name);
    }

    public static void main(String[] args) {
        show("Ayan");
    }
}

🎉 Great job! Continue learning Java step by step.