🧹🚩 REMOVE FLAG ARGUMENT REFACTORING (MAKE YOUR METHODS SAY WHAT THEY DO)
🧹🚩 REMOVE FLAG ARGUMENT REFACTORING (MAKE YOUR METHODS SAY WHAT THEY DO)
🔸 ✅ TL;DR
Flag arguments (boolean/enum/string) make methods do multiple jobs. Split them into explicit methods (or objects) so the code tells the truth: premium vs regular is visible, testable, and easier for tooling to analyze.
🔸 THE PROBLEM: “FLAG ARGUMENTS” HIDE INTENT 🤯
A flag argument is when a method changes behavior based on a parameter like:
▪️ boolean isPremium ✅
▪️ String mode = "PREMIUM" 😬
▪️ enum Tier { PREMIUM, REGULAR } ✅ (better than String, still a flag)
It works, but it forces readers (and tools) to mentally simulate branches: “What happens when it’s premium… and when it’s not?” 🧠💥
🔸 BEFORE: ONE METHOD, MULTIPLE PERSONALITIES 🎭
public Invoice total(User user, boolean premium) {
if (premium) {
return premiumTotal(user); // special rules 💎
}
return regularTotal(user); // standard rules 🧾
}
Or worse with Strings 😅:
public Invoice total(User user, String mode) {
if ("PREMIUM".equals(mode)) { ... }
else { ... }
}
🔸 AFTER: SPLIT INTO EXPLICIT METHODS (OR OBJECTS) ✅
public Invoice totalPremium(User user) {
return premiumTotal(user);
}
public Invoice totalRegular(User user) {
return regularTotal(user);
}
Even better if you want a single entry point:
public Invoice total(User user, Tier tier) {
return switch (tier) {
case PREMIUM -〉> totalPremium(user);
case REGULAR -〉 totalRegular(user);
};
}
➡️ The key: the premium vs regular logic becomes named, not hidden behind a flag.
🔸 WHY IT’S WORTH IT (HUMANS + TOOLS) 🤝🛠️
▪️ Clearer intent: totalPremium() reads like a sentence.
▪️ Fewer “what does true mean?” moments: total(user, true) is ambiguous.
▪️ Better code analysis: premium logic and regular logic become separate “units” → tools can reason about them more precisely (complexity, coverage, duplication, hotspots).
▪️ Easier to test: one behavior per method → smaller, focused tests.
▪️ Safer evolution: adding “VIP” later is cleaner than expanding a growing if/else tree.
🔸 WHEN FLAGS ARE A SMELL 🚨
▪️ If the method name doesn’t explain the argument (doStuff(user, true) 🤡)
▪️ If the method has multiple branches + different rules
▪️ If reviewers keep asking “what does this mode do?”
🧠 TAKEAWAYS
▪️ Prefer explicit method names over true/false behaviors.
▪️ If you must keep a single entry point, delegate to named methods.
▪️ Your future self (and your static analysis tools) will thank you. 😄
#Refactoring #CleanCode #SoftwareDesign #Java #CodeQuality #Testing #SOLID #Maintainability #DeveloperTools #StaticAnalysis
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