Awesome! Let’s dive into Day 9 of your Java programming journey, covering Method Overloading.

🚀 Java Programming – Day 9: Method Overloading from A to Z

📘 What is Method Overloading?

Method Overloading means creating multiple methods with the same name in the same class, but with different parameters (type, number, or order).

👉 It helps write clean, readable code by logically grouping related actions under one method name.

📌 Syntax:

class Demo {
    void show() {
        System.out.println("No parameters");
    }

    void show(int a) {
        System.out.println("Integer: " + a);
    }

    void show(String b) {
        System.out.println("String: " + b);
    }
}

🧠 Why Method Overloading?

• Makes code more readable
• Avoids method name confusion
• Implements polymorphism (compile-time)
• Useful in real-world scenarios like input validation, data formatting, calculations, etc.

🔁 How Overloading Works:

✅ Valid Overloading:

❌ What is NOT Overloading?

• Changing only the return type is NOT overloading.

int show() { }  
float show() { } // ❌ Compile-time error: same signature

🧪 Examples – A to Z

🔤 A. Adding numbers

int add(int a, int b) {
    return a + b;
}

float add(float a, float b) {
    return a + b;
}

🔤 B. Bank – Deposit system

void deposit(int amount) { }
void deposit(String chequeNumber) { }

🔤 C. Calculator

int calc(int a, int b) { return a + b; }
double calc(double a, double b) { return a * b; }

🔤 D. Display

void display(String name) { }
void display(String name, int age) { }

🔤 E. Email Sender

void send(String to) { }
void send(String to, String subject) { }
void send(String to, String subject, String msg) { }

🔤 Z. Zipping files (hypothetical)

void zip(String file) { }
void zip(String[] files) { }
void zip(String file, String destination) { }

⚙ How Java Resolves Overloaded Methods:

• Based on method signature
• Uses automatic type conversion if needed

void print(double d) { }
void print(String s) { }

print(10); // matches double (int → double)

⚠ Method Overloading vs Method Overriding:

✅ Real-Life Example:

class Greet {
    void hello() {
        System.out.println("Hello!");
    }

    void hello(String name) {
        System.out.println("Hello, " + name);
    }

    void hello(String name, int age) {
        System.out.println("Hello " + name + ", age: " + age);
    }
}

🧠 Conclusion – What I Understood:

• Method overloading is like giving multiple entry points for a single behavior.
• Java allows overloading based on parameter types and counts.
• Overloading increases readability, flexibility, and code reuse.
• Java does not allow overloading by return type only.