ATG Page Developer’s Guide

Given the previous XML document, you can use a JSP to read the XML document and retrieve data from it for display. The JSP performs these tasks:

Transforming XML to DOM

The JSP processes the XML document by calling the servlet bean XMLToDOM . XMLToDom obtains the XML document widgetorders and converts it into a DOM document. The servlet bean’s input parameter is set to orders.xml—the relative URL of the XML document:

<%-- Convert the XML document into a DOM object --%>
<dsp:droplet name="/atg/dynamo/droplet/xml/XMLToDOM">
  <dsp:param name="input" value="orders.xml"/>
  <dsp:param name="validate" value="false"/>

  <%--if conversion succeeds--%>
  <dsp:oparam name="output">
  ...
  </dsp:oparam>

  <%--if conversion fails--%>
  <dsp:oparam name="failure">
  ...
  </dsp:oparam>

</dsp:droplet>

XMLToDom has two open parameters whose bodies conditionally execute, depending on whether the transformation succeeds or fails:

Processing DOM nodes

If XMLToDOM succeeds, it executes the contents of its open parameter output. In this example, the output body calls the servlet bean NodeForEach, which iterates over the specified DOM nodes and performs these tasks:

<%--if conversion succeeds--%>
<dsp:oparam name="output">

  <%--from first order node, select each node where account = 86666--%>
  <dsp:droplet name="/atg/dynamo/droplet/xml/NodeForEach">
    <dsp:param name="node" param="document.firstChild"/>
    <dsp:param name="select"
    value="/widget-orders[position()=1]/order[@account='86666']"/>

    <%-- Case where none found --%>
    <dsp:oparam name="empty">
      No orders found.
    </dsp:oparam>

    <%-- if data found, start output --%>
    <dsp:oparam name="outputStart">
      <table>
        <tr>
          <td>Order ID</td>
          <td>Order Status</td>
        </tr>
    </dsp:oparam>
    <%-- output value of order node's id attribute --%>
    <dsp:oparam name="output">
      <tr>
        <td> <dsp:valueof param="element.id.nodeValue"/> </td>

        <%-- get child node order-status, display its value --%>
          <dsp:droplet name="/atg/dynamo/droplet/xml/NodeMatch">
          <dsp:param name="node" param="element"/>
          <dsp:param name="match" value="order-status/text()"/>
          <%-- Case where match is successful --%>
          <dsp:oparam name="output">
            <td> <dsp:valueof param="matched.nodeValue"/> </td>
          </dsp:oparm>
        </dsp:droplet>
      </tr>
    <%-- end NodeForEach output --%>
    </dsp:oparam>

    <%-- close table --%>
    <dsp:oparam name="outputEnd">
      </table>
    </dsp:oparam>

  <%-- close NodeForEach droplet --%>
  </dsp:droplet>
<%-- close XMLToDOM output --%>
</dsp:oparam>

Handling DOM conversion failure

If the XML-to-DOM conversion fails, the XMLToDOM servlet bean executes its open parameter failure:

<%-- If conversion fails --%>
<dsp:oparam name="failure">
  Failure to parse XML document: <dsp:valueof param="input"/> <br/>
</dsp:oparam>