title: Why doesn't Integer.parseInt("1")++ work in Java?
body: <p>I've got the following line of code:</p>
  
  <pre><code>suffix = suffix.isEmpty() ? "1" : Integer.toString(Integer.parseInt(suffix)+1);
  </code></pre>
  
  <p>in a block where suffix has already been declared as an empty String (<code>""</code>). The block is looking for duplicate file names and adding a number on to any duplicates so they don't have the same name any more.</p>
  
  <p>The line of code above compiles fine, but if I change it to this, </p>
  
  <pre><code>suffix = suffix.isEmpty() ? "1" : Integer.toString(Integer.parseInt(suffix)++);
  </code></pre>
  
  <p>I get <code>Invalid argument to operation ++/--</code>. Since <code>Integer.parseInt()</code> returns and int, why can't I use the <code>++</code> operator?</p>