Good variable names make stored values read like characters in a story: they reveal purpose, reduce cognitive load, and warn against careless changes. section 2.4
Use names that communicate both the value and its role:
- Prefer nouns for data, plural nouns for collections, question-like names for booleans, and verbs for action-oriented lambdas. section 2.4
- Choose domain vocabulary consistently; switching between terms such as client, user, and visitor creates confusion. section 2.4
- Avoid single-letter, generic, or ambiguous names such as x, temp, flag, and data, except for familiar loop variables. section 2.4
- Keep variables near their use and within the smallest possible scope; excessive temporaries can obscure the central logic. section 2.4
Listing 2.6 Scene-level method building promotional email content
public String buildPromotionalEmailContent(long userId) {
String emailContent; #1
User user = userService.findUserById(userId); #2
boolean isUserBirthday = isToday(user.getBirthday());
if (isUserBirthday) {
List<Promotion> birthdayPromotions = #3
promotionService.getPromotionsFor(user); #3
emailContent = birthdayPromotionEmailFor(user, birthdayPromotions);
} else {
List<Promotion> standardPromotions = #3
promotionService.getPromotionsFor(user); #3
emailContent = regularPromotionEmailFor(user, standardPromotions);
}
return emailContent;
}
Compare the crowded promotional-email method with its clearer revision: descriptive names, localized scope, and fewer intermediate variables expose the main flow. section 2.4
