title: In Java, should Integer object be preferred over int primitive (same for other numeric types)?
body: <p>Ok, so I understand that Integer is simply a wrapper class. however my concern is that avoiding to use a "wrapper", there might be a micro-optimization in execution time when using primitive ints variables.</p>
  
  <p>My question is regarding, is really Integer object the one we should prefer to use, specially in programs which are required to have great performance(with great I mean, heavy duty, O(N^n) algorithms, the ones that take days).</p>
  
  <p>Also, same case for double vs Double, float vs Float , etc.</p>