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Clean code: rename for intent
Principles · Java
Clean code: rename for intent
Make every name say what it means, so the next change lands right.
15 steps
4 chapters
~4 min at 1.25×
#naming
#readability
#rename
#magic numbers
Language
Java
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Every step
Problem
Steps 1–3
01
A late fine that works
Before
02
A grace period that never applies
Code smell
03
Undo, then rename
Plan
Refactor
Steps 4–12
04
d becomes daysOut
Rename Field
05
f becomes student
Rename Field
06
x becomes daysLate
Rename Variable
07
r becomes dailyRate
Rename Variable
08
l becomes loan
Rename Parameter
09
Name the loan period
Replace Magic Number
10
Name the two rates
Replace Magic Number
11
Name the cap
Replace Magic Number
12
calc becomes overdueFine
Rename Method
Payoff
Step 13
13
The grace period, right the first time
Payoff
Recap
Steps 14–15
14
Where we started, where we ended
Before / after
15
When to reach for it
Takeaways