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Manoj
Manoj

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Java Command Line Arguments

Imagine you're teaching your dog a new trick. You wouldn't just yell "Fetch!" and hope for the best, right? You'd give clear instructions, maybe even offer a treat for understanding. That's how you communicate with your Java program using command line arguments: you give it specific instructions at runtime to customize its behavior.

But let's ditch the dog analogy and dive into what command line arguments actually are. They're like whispers you tell your program before it starts running. You pass them as strings after the program name when you run it from the command prompt. These whispers can be anything from file names to specific actions, telling your program exactly what you want it to do.

Think of it like ordering a pizza. You wouldn't just say "Food!" You'd specify the size, crust, toppings, and maybe even a delivery time. Command line arguments are like your pizza order, giving your program all the details it needs to do its job well.

Why Use Command Line Arguments?

There are many reasons to use command line arguments. Here are a few:

Make your program flexible: Instead of hardcoding everything into the program itself, you can let users adjust settings or input data through arguments. This makes your program more versatile and adaptable.
Automate tasks: You can use arguments to automate repetitive tasks, like processing multiple files or running your program with different configurations. No more clicking and typing!
Simplify testing: Different arguments can trigger different program behaviors, making it easier to test various scenarios and functionalities. Debugging becomes a breeze.
Getting Started with Arguments:

Now, let's get your hands dirty with some actual code. We'll write a simple program that takes a file name as an argument and prints its contents. Here's the basic structure:

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