Github user stokito commented on the issue:
https://github.com/apache/commons-lang/pull/334
I checked and everything is ok in terms of backward compatibility. But the
commit 7f8571a506c7081bae0cf27bd93295e0344160bf "flips the order of conditional
expressions and 'if' statements whose conditions were negated." may be not so
good in terms of code readability.
First of all, there is always some natural flow when we expect that
something is more likely happens.
Let's take a look on the method `addProcessor()`:
```java
private static void addProcessor(final String key, final Processor
processor) {
if (!ARCH_TO_PROCESSOR.containsKey(key)) {
ARCH_TO_PROCESSOR.put(key, processor);
} else {
final String msg = "Key " + key + " already exists in processor
map";
throw new IllegalStateException(msg);
}
}
```
Here developer sees a "happy path" first and only then he or she sees
exception situation handling.
This is more natural to understand. As I remember this style was mentioned
in Complete Code book.
Also this style has slightly better performance because in most situations
processor will go forward to prefetched instructions or even it can be already
executed by [branch prediction](https://en.wikipedia.org/wiki/Branch_predictor).
Meanwhile removing of negation usually doesn't have any performance impact
because processors have already negated instructions.
I thinks it's ok to merge this commit but I just wan't you to know that
sometimes it is better to make unnecessary negation.
---
