title: can I check if a file exists at a URL?
body: <p><a href="https://stackoverflow.com/questions/1979915/can-i-check-if-a-file-exists-at-a-url">can I check if a file exists at a URL?</a></p>
  
  <p>This link is very good for C#, what about java. I serach but i did not find good solution.</p>