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Gareth Gray
Gareth Gray
3,336 Points

Overriding equals() question.

Wondering if anyone can explain these lines.

if (mArtist != null ? !mArtist.equals(song.mArtist) : song.mArtist != null) return false;
if (mTitle != null ? !mTitle.equals(song.mTitle) : song.mTitle != null) return false;

I understand how ?: works as if-then-else but I'm a bit muddled with what's going on here and why it's needed. It's the not-equals operand that is throwing me I think...

Gareth Gray
Gareth Gray
3,336 Points

Okay I think I've got it! It's the ternary within an 'if statement' that got me.

Basically it's checking if mArtist is null first. If it is null and song.mArtist isn't, return false (they aren't equal) If mArtist isn't null, it checks !mArtist.equals(song.mArtist) and returns false if true...

That was mind bending....!