Static and Non-Static Methods in Java:

Introduction

Java methods can be categorized into two main types: static and non-static methods. Understanding the difference between them is crucial for writing efficient and well-structured Java programs.

In this blog, we will explore static and non-static methods, their differences, and provide real-world examples to help you grasp their implementation effectively.

What is a Method in Java?

A method in Java is a block of code that performs a specific task. Methods help eliminate redundancy, increase code efficiency, and make debugging easier. Every method is part of a class and executes when it is called.

Syntax of a Method

returnType methodName(parameters) {
    // Method body
    return value; // (if required)
}

Enter fullscreen mode Exit fullscreen mode

Static Methods in Java

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

Characteristics of Static Methods:

• Defined using the static keyword.
• Can be called using the class name.
• Cannot access instance variables directly.
• Used for utility or helper methods.

Example of a Static Method:

public class StaticExample {
    // Static method
    public static void displayMessage() {
        System.out.println("Hello from a static method!");
    }

    public static void main(String[] args) {
        // Calling the static method using class name
        StaticExample.displayMessage();
    }
}

Enter fullscreen mode Exit fullscreen mode

Output:

Hello from a static method!

Enter fullscreen mode Exit fullscreen mode

Non-Static Methods in Java

A non-static method (also called an instance method) requires an object of the class to be called.

Characteristics of Non-Static Methods:

• Do not use the static keyword.
• Can access both static and instance variables.
• Require an object to be invoked.
• Used when the method needs to operate on instance data.

Example of a Non-Static Method:

public class NonStaticExample {
    // Non-static method
    public void showMessage() {
        System.out.println("Hello from a non-static method!");
    }

    public static void main(String[] args) {
        // Creating an object to call the non-static method
        NonStaticExample example = new NonStaticExample();
        example.showMessage();
    }
}

Enter fullscreen mode Exit fullscreen mode

Output:

Hello from a non-static method!

Enter fullscreen mode Exit fullscreen mode

Key Differences Between Static and Non-Static Methods

Example: Static vs. Non-Static Methods Together

public class MethodComparison {
    // Static method
    public static void staticMethod() {
        System.out.println("This is a static method.");
    }

    // Non-static method
    public void nonStaticMethod() {
        System.out.println("This is a non-static method.");
    }

    public static void main(String[] args) {
        // Calling static method without creating an object
        MethodComparison.staticMethod();

        // Creating an object to call non-static method
        MethodComparison obj = new MethodComparison();
        obj.nonStaticMethod();
    }
}

Enter fullscreen mode Exit fullscreen mode

Output:

This is a static method.
This is a non-static method.

Enter fullscreen mode Exit fullscreen mode

When to Use Static and Non-Static Methods?

Use static methods when:
The method does not need to access instance variables.
You want to create utility or helper methods (e.g., Math.sqrt()).
Memory optimization is a priority (since static methods are loaded once).

Use non-static methods when:
The method needs to operate on instance data.
The behavior should change depending on object state.
Object-specific functionality is required.

Conclusion

Understanding static and non-static methods in Java is crucial for writing clean and optimized code. Static methods are used for common functionalities, while non-static methods allow working with instance variables.

Start using these concepts in your Java projects and level up your programming skills today!

原文链接：Static and non static methods in java…