title: which is best between string isEmpty and StringUtils.isNotBlank()
body: <p>I use the following code to check timing:</p>
  
  <pre><code>public static void main(String[] args) throws Exception {
      String foo = "foo";
      long start=System.currentTimeMillis();
      if (StringUtils.isBlank(foo));
      long end=System.currentTimeMillis();
      System.out.println("isBlank="+(end-start));
      start=System.currentTimeMillis();
      if (foo!=null &amp;&amp; !foo.isEmpty());
      end=System.currentTimeMillis();
      System.out.println("Sec="+(end-start));
  }
  </code></pre>
  
  <p>The StringUtils.isBlank() method takes 3ms longer than a simple String.isEmpty() method. Which method should we use?</p>