Ternary Operator and unexpected NullPointerException

Question

I am getting NullPointerException from the below line sometimes.

System.out.println(\"Date::\"+ row != null ? row.getLegMaturityDate() : \"null         


        

Answer 1

"Date::" + row is never null, although row sometimes is.

That is, "Date::"+ row != null is equivalent to ("Date::"+ row) != null which is always true.

Answer 2

It's a matter of operator precedence. Christoffer Hammarström has the executive summary. See this page http://bmanolov.free.fr/javaoperators.php for more detail.