包含多个if条件的java重构代码
以下是我为保存UrlEntity而编写的一些代码:
public UrlEntity saveUrlEntity(String longUrl, LocalDate dateAdded) {
int urlLength = longUrl.length();
if (urlLength >= Constants.MAX_LONG_URL_LENGTH) {
throw new LongUrlLengthExceededException("URL with length " + urlLength + " exceeds the max length of " + Constants.MAX_LONG_URL_LENGTH + " characters");
} else {
List<UrlEntity> urlEntity = urlRepository.findByLongUrl(longUrl);
if (urlEntity.size() > 0) {
return urlEntity.get(0);
} else {
final String shortUrl = urlShorten.shortenURL(longUrl);
if (urlRepository.findFirstByShortUrl(shortUrl).isPresent()) {
logger.error("A short short URL collision occured for long URL: " + longUrl + " with generated short URL" + shortUrl);
throw new ShortUrlCollisionException("A short URL collision occured");
} else {
logger.info("Shortened URL: " + shortUrl);
final UrlEntity urlEntityToSave = new UrlEntity(dateAdded, longUrl, shortUrl);
return urlRepository.save(urlEntityToSave);
}
}
}
}
上面的代码存在于服务类中,看起来非常复杂。我正在尝试重构,以使意图清晰。这是我写的一个基本重构:
public UrlEntity saveUrlEntity(String longUrl, LocalDate dateAdded) {
int urlLength = longUrl.length();
if (urlLength >= Constants.MAX_LONG_URL_LENGTH) {
throw new LongUrlLengthExceededException("URL with length " + urlLength + " exceeds the max length of " + Constants.MAX_LONG_URL_LENGTH + " characters");
} else {
List<UrlEntity> urlEntity = urlRepository.findByLongUrl(longUrl);
if (urlEntity.size() > 0) {
return urlEntity.get(0);
} else {
return saveUrlEntityValue(longUrl, dateAdded);
}
}
}
private UrlEntity saveUrlEntityValue(String longUrl, LocalDate dateAdded){
final String shortUrl = urlShorten.shortenURL(longUrl);
if (urlRepository.findFirstByShortUrl(shortUrl).isPresent()) {
logger.error("A short short URL collision occured for long URL: " + longUrl + " with generated short URL" + shortUrl);
throw new ShortUrlCollisionException("A short URL collision occured");
} else {
logger.info("Shortened URL: " + shortUrl);
final UrlEntity urlEntityToSave = new UrlEntity(dateAdded, longUrl, shortUrl);
return urlRepository.save(urlEntityToSave);
}
}
这种重构并没有实质性地改进代码。有没有代码模式或惯用方法来重构方法saveUrlEntity
?我正在使用Java11
# 1 楼答案
这是非常主观的,但是。。。由于大多数
if
语句都是保护/短路子句,它们是throw
或return
,因此不需要使用else
。我认为这个简单的更改使代码更具可读性我还建议将
urlEntity.size() > 0
替换为!urlEntity.isEmpty()
这种方法似乎确实在做几件事,这违反了单一责任原则;你可能想更好地解决这个问题
# 2 楼答案
如果使用
throw new
或return
,则不需要else条件,因为该方法以