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| <title>Write DOM Session Transformer</title> |
| <link href="http://purl.org/DC/elements/1.0/" rel="schema.DC"> |
| <meta content="Carsten Ziegeler" name="DC.Creator"> |
| <meta content="Sven Beauprez" name="DC.Creator"> |
| <meta content="Davanum Srinivas" name="DC.Creator"> |
| <meta content="This document describes the write dom session transformer of Cocoon." name="DC.Description"> |
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| |
| <h1>Write DOM Session Transformer</h1> |
| |
| <p>Make a DOM object from SAX events and write it to the session.</p> |
| |
| <ul> |
| |
| <li>Name : writeDOMsession</li> |
| |
| <li>Class: org.apache.cocoon.transformation.WriteDOMSessionTransformer</li> |
| |
| <li>Cacheable: no.</li> |
| |
| </ul> |
| |
| <p> |
| If you only use the FilterTransformer in combination with the SQLTransformer, |
| you have to query the database each time the user wants to see another part of |
| the result. You can better store the result in the session after the first |
| request and retrieve the result from the session for the subsequent requests. |
| This can be done by using a selector, which checks if the data is available in |
| the session or not. |
| </p> |
| |
| <p> |
| WriteDOMSessionTransformer can build a DOM starting from a given element (which |
| will be the root of the DOM tree) and store it in the session. If you want to |
| store the result of a query, you have to add following to the sitemap: |
| </p> |
| |
| <pre class="code"> |
| |
| <map:transform type="writeDOMsession"> |
| <map:parameter name="dom-name" value="DBresult"/> |
| <map:parameter name="dom-root-element" value="rowset"/> |
| </map:transform> |
| |
| </pre> |
| |
| <p> |
| The transformer will build a DOM tree with rowset as root element and will store |
| it in the session with the name "DBresult". |
| </p> |
| |
| <p> |
| Note: most of the times, it is not smart to keep the output XML of the |
| SQLTransformer in the session. Check if it is better to do the necessary |
| transformations first, so that you get a smaller DOM, and then put the result in |
| the session. You probably will be able to use the FilterTransformer on the |
| transformed XML also. |
| </p> |
| |
| <p> |
| The WriteDOMSessionTransformer is a standalone component, you don't need to use |
| it in combination with the SQLTransformer. |
| </p> |
| |
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