code: public Element appendToXml(Element parentNode, List<String> parametersToIgnore) {
  
          for (Map.Entry<String, Serializable> entry : m_configurationObjects.entrySet()) {
              String name = entry.getKey();
              // check if the parameter should be ignored
              if ((parametersToIgnore == null) || !parametersToIgnore.contains(name)) {
                  // now serialize the parameter name and value
                  Object value = entry.getValue();
                  if (value instanceof List) {
                      @SuppressWarnings("unchecked")
                      List<String> values = (List<String>)value;
                      for (String strValue : values) {
                          // use the original String as value
                          Element paramNode = parentNode.addElement(I_CmsXmlConfiguration.N_PARAM);
                          // set the name attribute
                          paramNode.addAttribute(I_CmsXmlConfiguration.A_NAME, name);
                          // set the text of <param> node
                          paramNode.addText(strValue);
                      }
                  } else {
                      // use the original String as value
                      String strValue = get(name);
                      Element paramNode = parentNode.addElement(I_CmsXmlConfiguration.N_PARAM);
                      // set the name attribute
                      paramNode.addAttribute(I_CmsXmlConfiguration.A_NAME, name);
                      // set the text of <param> node
                      paramNode.addText(strValue);
                  }
              }
          }
  
          return parentNode;
      }
docs: Serializes this parameter configuration for the OpenCms XML configuration.<p>
  
  For each parameter, a XML node like this<br>
  <code>
  &lt;param name="theName"&gt;theValue&lt;/param&gt;
  </code><br>
  is generated and appended to the provided parent node.<p>
  
  @param parentNode the parent node where the parameter nodes are appended to
  @param parametersToIgnore if not <code>null</code>,
  all parameters in this list are not written to the XML
  
  @return the parent node