Criação do controle de classificação

Código java do controle responsável para calcular a média entre valores de N campos, que dinamicamente crie subcontroles para os campos envolvidos no cálculo, executando-o client-side:

package corporate.hoteisadmin6;
import org.w3c.dom.Node;
import lumis.doui.control.DataBoundControl;
import lumis.portal.PortalException;
import lumis.util.XmlUtil;
public class ClassificacaoControl extends DataBoundControl
{
 public void buildSubControls() throws PortalException
 {
  super.buildSubControls();
 
  Node[] fieldNodes = XmlUtil.selectNodes("fields/field", controlDefinitionNode);
  Node outputFieldNode = XmlUtil.selectSingleNode("outputField", controlDefinitionNode);
  String outputFieldId = XmlUtil.readAttributeString("id", outputFieldNode);
 
  if(fieldNodes == null || fieldNodes.length == 0 || outputFieldNode == null)
   return;
 
  StringBuilder scriptControlXmlString = new StringBuilder();
 
  scriptControlXmlString.append("<control type=\"lum_script\">");
  scriptControlXmlString.append("<script>function atualizaMedia() {");
  scriptControlXmlString.append("var iSoma = 0;");
 
  StringBuilder subControlsXmlString = new StringBuilder();
 
  subControlsXmlString.append(XmlUtil.XML_HEADER);
  subControlsXmlString.append("<controls>");
 
  subControlsXmlString.append("<control type=\"lum_table\">");
 
  for(Node fieldNode : fieldNodes)
  {
   String fieldId = XmlUtil.readAttributeString("id", fieldNode);
  
   subControlsXmlString.append("<tr>");
   subControlsXmlString.append("<td>");
   subControlsXmlString.append("<control type=\"lum_label\" dataId=\"");
   subControlsXmlString.append(fieldId);
   subControlsXmlString.append("\"></control>");
   subControlsXmlString.append("</td>");
   subControlsXmlString.append("<td>");
   subControlsXmlString.append("<control type=\"lum_dropDownList\" id=\"");
   subControlsXmlString.append(fieldId);
   subControlsXmlString.append("\" onChange=\"javascript:atualizaMedia();\"></control>");
   subControlsXmlString.append("</td>");
   subControlsXmlString.append("</tr>");
  
   scriptControlXmlString.append("if(document.getElementById('");
   scriptControlXmlString.append(fieldId);
   scriptControlXmlString.append("').value){"); 
   scriptControlXmlString.append("iSoma += parseInt(document.getElementById('");
   scriptControlXmlString.append(fieldId);
   scriptControlXmlString.append("').value);}");  
  }
 
  subControlsXmlString.append("<tr>");
  subControlsXmlString.append("<td>");
  subControlsXmlString.append("<control type=\"lum_label\" dataId=\"");
  subControlsXmlString.append(outputFieldId);
  subControlsXmlString.append("\"></control>");
  subControlsXmlString.append("</td>");
  subControlsXmlString.append("<td>");
  subControlsXmlString.append("<control type=\"lum_inputText\" id=\"");
  subControlsXmlString.append(outputFieldId);
  subControlsXmlString.append("\" readonly=\"true\" style=\"width:35px\"></control>");
  subControlsXmlString.append("</td>");
  subControlsXmlString.append("</tr>");
  
  subControlsXmlString.append("</control>");
 
  scriptControlXmlString.append("iSoma = iSoma / ");
  scriptControlXmlString.append(fieldNodes.length);
  scriptControlXmlString.append(";");
  scriptControlXmlString.append("document.getElementById('");
  scriptControlXmlString.append(outputFieldId);
  scriptControlXmlString.append("').value = iSoma + '';}</script></control>");
 
  subControlsXmlString.append(scriptControlXmlString);
 
  subControlsXmlString.append("</controls>");
 
  appendSubControls(subControlsXmlString.toString());
 }
}