title: java String split(String, int)
body: <p>Really confusing about these two methods, having looked into the API doc of <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#split(java.lang.String,%20int)" rel="nofollow">split (String, int)</a> , 
  still not sure when empty space will emerge.</p>
  
  <p>For example </p>
  
  <pre><code>String s="boo:and:foo"
  s.split("o", -2);
  //the result, according to doc is { "b", "", ":and:f", "", "" }
  //why there is only one "" string in the front, while two "" in the back?
  </code></pre>
  
  <p>My thought after some testing is whenever there is consecutive match, in this case oo, there will be an additional "" , for the last trailing ""
      It is because of a match right before the end of String + consecutive match, resulting in <strong>two</strong> (the match right before the start of string will also result in a leading "")</p>
  
  <p>Some confirmation needed. </p>