Modern Java in Action: The Challenge of Changing Requirements

Imagine a local orchard owner who initially only needs to track "Green Apples" for a tart recipe. As the season progresses, they suddenly need "Red Apples" for cider. If your software is hardcoded for GREEN, you are trapped in a cycle of constant recompilation.

1. The Rigidity of Hardcoding

Methods like filterGreenApples are brittle. They bake specific business rules directly into the control flow. Every minor change (like a new color) requires a full deployment, creating a codebase that resists change rather than embracing it.

2. The Duplication Trap

Without behavior parameterization, developers often fall into copy-paste programming. Creating near-identical methods for every new requirement increases the surface area for bugs and maintenance overhead exponentially. Value parameterization is the first defense: passing the color as an argument to make the logic reusable.

TERMINAL bash — 80x24

> Ready. Click "Run" to execute.

QUESTION 1

How do we avoid duplicating most of the code in filterGreenApples to make filterRedApples?

By copy-pasting the logic into a new method called filterRedApples.

By adding a Color parameter to the method and using it in the comparison logic.

By using a global constant for the color.

By rewriting the entire inventory system to use a Database query.

QUESTION 2

What is the primary danger of the 'Copy-Paste' programming trap mentioned in the lesson?

It makes the code too fast to execute.

It significantly increases maintenance overhead and the potential for bugs.

It reduces the number of classes in the project.

It automatically fixes logic errors in the original code.

QUESTION 3

Which term describes a method that bakes specific business rules directly into its control flow?

Abstract

Brittle

Polymorphic

Decoupled

QUESTION 4

What is the first evolutionary step to mitigate code duplication when requirements change?

Implementing a full Lambda architecture.

Refactoring hardcoded values into method parameters.

Deleting the requirements document.

Creating a separate class for every possible color.

QUESTION 5

Why does hardcoding 'GREEN' in a filter method require a full re-compile for a 'RED' apple request?

Because the color is part of the compiled bytecode's logic flow.

Java does not support red colors by default.

The inventory list only accepts green objects.

Method names cannot be changed at runtime.