title: how to achieve {0} in struts2 Field validation message
body: <p>How to achieve parameterized message in struts2.
  in actioname-validation.xml i have </p>
  
  <pre><code>&lt;field name="family.familyName"&gt;
          &lt;field-validator type="requiredstring"&gt;
              &lt;param name="trim"&gt;true&lt;/param&gt;
              &lt;message key="common.required"&gt;
                  &lt;argo key="common.family" /&gt;
              &lt;/message&gt;
          &lt;/field-validator&gt;
      &lt;/field&gt;
  </code></pre>
  
  <p>resource file i have,</p>
  
  <pre><code>common.required = {0} is required.
  common.family = Family
  </code></pre>
  
  <p>some thing like this i tried. how to achive this?</p>