Hello and welcome to today’s one-minute dive into a classic Java head-scratch. On The Daily WTF, we meet Alice’s co-worker, who runs a query, pulls every row into a List by doing “result.add(new Integer(rs.getInt(1)))” and then immediately copies it into an int[] array. As the author points out, since Java 5 you get automatic boxing and unboxing—so you don’t need “new Integer” or “((Integer) result.get(h)).intValue()”. Even more puzzling is creating that fixed-size array just after populating a dynamically resizable ArrayList. The article calls it “probably a premature optimization,” and suggests our coder might just be stuck in a C mindset: “comfortable with an array of integers, which covers 90% of the data types you use in C.” In the end, a few extra lines of code add zero benefit and cost precious readability. That’s your minute of WTF—keep your Java simple, and let the JVM handle your boxing.
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