SimpleClass in 10 Minutes: Quick Start Tutorial—
This quick-start tutorial walks you through the essentials of SimpleClass — a minimal, easy-to-understand class pattern you can use to structure code in many languages. In about ten minutes you’ll learn what SimpleClass is, why and when to use it, how to implement it in several languages, and some practical tips for extending and testing it.
What is SimpleClass?
SimpleClass is a minimal, single-purpose class pattern intended to encapsulate related data and behavior with a clear, small public interface. It focuses on readability, testability, and ease of use, making it a great starting point for beginners or a lightweight building block in larger systems.
Why use SimpleClass?
- Clear separation of concerns: groups related state and methods together.
- Easier testing: small surface area simplifies unit tests.
- Readability: straightforward structure for other developers.
- Reusability: a small class can be composed into larger systems.
Core principles
- Single responsibility: one main purpose.
- Small public API: expose only what’s needed.
- Immutable by default (when possible): prefer read-only state.
- Explicit dependencies: pass collaborators via constructor.
- Simple lifecycle: clear construction and destruction rules.
Example implementations
Below are concise implementations of SimpleClass in several popular languages. Each example demonstrates a class that stores a name and a counter, with methods to increment and format the name and count.
Python (3.x)
class SimpleClass: def __init__(self, name: str, start: int = 0): self._name = name self._count = start @property def name(self) -> str: return self._name @property def count(self) -> int: return self._count def increment(self, by: int = 1) -> int: self._count += by return self._count def display(self) -> str: return f"{self._name}: {self._count}" Usage:
obj = SimpleClass("Counter", 5) obj.increment() print(obj.display()) # Counter: 6 JavaScript (ES6)
class SimpleClass { constructor(name, start = 0) { this._name = name; this._count = start; } get name() { return this._name; } get count() { return this._count; } increment(by = 1) { this._count += by; return this._count; } display() { return `${this._name}: ${this._count}`; } } Usage:
const obj = new SimpleClass('Counter', 5); obj.increment(); console.log(obj.display()); // Counter: 6 Java
public class SimpleClass { private final String name; private int count; public SimpleClass(String name, int start) { this.name = name; this.count = start; } public String getName() { return name; } public int getCount() { return count; } public int increment(int by) { count += by; return count; } public String display() { return name + ": " + count; } } Usage:
SimpleClass obj = new SimpleClass("Counter", 5); obj.increment(1); System.out.println(obj.display()); // Counter: 6 C# (.NET)
public class SimpleClass { public string Name { get; } private int _count; public int Count => _count; public SimpleClass(string name, int start = 0) { Name = name; _count = start; } public int Increment(int by = 1) { _count += by; return _count; } public string Display() => $"{Name}: {_count}"; } Usage:
var obj = new SimpleClass("Counter", 5); obj.Increment(); Console.WriteLine(obj.Display()); // Counter: 6 Quick extension ideas
- Add validation for inputs (e.g., non-empty name, non-negative increments).
- Make the class observable (callbacks/events when count changes).
- Add serialization (to/from JSON) for persistence or network transfer.
- Introduce interfaces/abstract base classes for easier mocking in tests.
Testing SimpleClass
Unit tests should be small and focused:
Python (pytest)
def test_increment_and_display(): s = SimpleClass("T", 0) assert s.increment() == 1 assert s.display() == "T: 1" JavaScript (Jest)
test('increment and display', () => { const s = new SimpleClass('T', 0); expect(s.increment()).toBe(1); expect(s.display()).toBe('T: 1'); }); Best practices and pitfalls
- Prefer immutability for fields that shouldn’t change after construction.
- Keep methods focused; avoid combining unrelated responsibilities.
- Avoid exposing internal state directly — use getters or read-only properties.
- Document edge cases (negative increments, overflow) so callers know behavior.
Quick reference: checklist
- [ ] Single responsibility
- [ ] Narrow public API
- [ ] Constructor injects dependencies/initial state
- [ ] Add unit tests for each method
- [ ] Consider validation and error handling
This should give you a compact but practical overview to build and use a SimpleClass in minutes.