title: Append leading zeros in jstl tag when the value is less than 10
body: <p>I have a select element in my jsp view. I want that when the value is less than 10, it appends <code>0</code> before the number so <code>1</code> will be <code>01</code>. So far this is my code:</p>
  
  <pre><code>   &lt;select id="sample" name="sample"&gt;
        &lt;c:forEach var="i" begin="1" end="10"&gt;
           &lt;option value=${i}&gt;${ i&lt;12 ? "0"+i  : i} hour&lt;/option&gt;
        &lt;/c:forEach&gt;
     &lt;/select&gt;
  </code></pre>
  
  <p>When I run my code I get a error <code>java.lang.NumberFormatException: For input string:</code>. What is wrong with my code? </p>