code: public StyleModel getStyleModel(String name, String classPrefix) {
          if(name == null || name.equals(STYLE_POLICY_NAME_DEFAULT)) {
              if(classPrefix != null)
                  return new DefaultStyleModel(classPrefix);
              else return DEFAULT_STYLE_POLICY;
          }
          else if(name != null && name.equals(STYLE_POLICY_NAME_EMPTY))
              return EMPTY_STYLE_POLICY;
          else return DEFAULT_STYLE_POLICY;
      }
docs: Get a {@link StyleModel} given a model name and a style class prefix.  This class exposes two available
  style names:
  <table>
  <tr><td>Name</td><td>Description</td><td>Implementation Class</td></tr>
  <tr><td><code>empty</code></td>
  <td>Renders CSS style classes that are non-prefixed and generally empty.</td>
  <td>{@link EmptyStyleModel}</td>
  </tr>
  <tr><td><code>default</code></td>
  <td>Renders CSS style classes with names using a default prefix of <code>datagrid</code></td>
  <td>{@link DefaultStyleModel}</td>
  </tr>
  </table>
  When using the <code>empty</code> style model, styles rendered on the &lt;table&gt; element will
  be empty; the same style rendered wtih the <code>default</code> style model will render as
  <code>class="datagrid"</code>.  If the style prefix "foo" is provided for the <code>default</code> style policy
  the style name will be rendered as <code>class="foo"</code>.x
  @param name the name of a {@link StyleModel} implementation to use
  @param classPrefix the prefix for a style name
  @return the style model