🧩🧹 SPLIT OVERLOADED CLASSES INTO SPECIFIC ONES (WITHOUT OVER-ENGINEERING)
🧩🧹 SPLIT OVERLOADED CLASSES INTO SPECIFIC ONES (WITHOUT OVER-ENGINEERING)
That Clean Code recommendation — “Split overloaded classes into specific ones.” — is basically a reminder about Single Responsibility: when a class does too many jobs, it becomes harder to understand, test, and change safely.
🔸 TLDR
▪️ If a class has multiple reasons to change, it’s overloaded. Split it into small, focused classes with clear names. ✅
🔸 WHY OVERLOADED CLASSES HURT
▪️ Every change risks breaking unrelated behavior 💥
▪️ Testing becomes painful (tons of mocks + huge setup) 🧪
▪️ The class becomes a “god object” nobody wants to touch 😅
▪️ Readability drops: you spend time finding logic instead of shipping features
🔸 SPOT THE SMELL (QUICK CHECKLIST)
▪️ The class name is vague: Manager, Handler, Service, Util 🤨
▪️ It has unrelated methods: validate(), format(), save(), notify() in the same file
▪️ Many dependencies injected “just in case”
▪️ Huge files: “scroll fatigue” 😵💫
▪️ You can describe it with “and”: It does X and Y and Z…
🔸 A SIMPLE REFACTOR PATTERN
▪️ Start by identifying responsibilities:
▪️ validation ✅
▪️ persistence 💾
▪️ external calls 🌐
▪️ formatting/DTO mapping 🔁
▪️ orchestration 🧭
▪️ Extract them into small classes with explicit names:
▪️ InvoiceValidator
▪️ InvoiceRepository
▪️ PaymentGatewayClient
▪️ InvoiceMapper
▪️ Keep a thin InvoiceService that orchestrates (not does everything)
🔸 KEEP IT PRACTICAL (NO “CLASS EXPLOSION”)
▪️ Don’t split just to split: split when it reduces coupling and clarifies intent
▪️ Prefer small cohesive units, but avoid turning every method into a new class 😄
▪️ Make the code tell a story through names 📖
🔸 TAKEAWAYS
▪️ Overloaded class = multiple responsibilities + multiple reasons to change
▪️ Split into specific classes with clear names
▪️ Tests get easier, changes get safer, and the codebase gets friendlier 💚
#CleanCode #SoftwareEngineering #Refactoring #Java #SpringBoot #Architecture #Maintainability #Testing #OOP #CodeQuality
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