amiro 01/07/19 05:49:46
Modified: java/samples/CompiledServlet README.servlet
Log:
Updated readme to reflect recent changes in the current XSLTC native API,
to mention the NAMESPACE_FEATURE constant, and to remove any anachronistic
mentions of the "Preview" distriubtion (that was pre Apache).
Revision Changes Path
1.2 +80 -53 xml-xalan/java/samples/CompiledServlet/README.servlet
Index: README.servlet
===================================================================
RCS file: /home/cvs/xml-xalan/java/samples/CompiledServlet/README.servlet,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- README.servlet 2001/05/17 15:36:40 1.1
+++ README.servlet 2001/07/19 12:49:46 1.2
@@ -1,65 +1,35 @@
-============================================================
+=======================================================================
CONTENTS OF THIS DOCUMENT:
o) HOW TO PROVIDE XSL TRANSFORMATIONS AS A WEB SERVICE
o) HOW TO INVOKE TRANSLETS FROM A SERVLET
o) BUILDING YOUR OWN DOM CACHE
-------------------------------------------------------------
+-----------------------------------------------------------------------
HOW TO PROVIDE XSL TRANSFORMATIONS AS A WEB SERVICE
-With XSLTC, XSL transformations can be run from within a
-servlet. The XSLTC preview package contains an example demonstrating
-how this can be done.
+With XSLTC, XSL transformations can be run from within a servlet.
+This sample code demonstrates how that can be implemented.
-------------------------------------------------------------
+The CompiledEJB and CompiledBrazil sample code demonstrate other
+aproaches to providing XSL transformations as a web service.
+
+-----------------------------------------------------------------------
HOW TO INVOKE TRANSLETS FROM A SERVLET
-The XSLTC preview package contains the example source code:
+The CompiledServlet directory contains the example source code:
TransformServlet.java
-
-This file contains a minimal implementation of an XSL
-transformation servlet. The servlet performs the same basic
-steps as the class implementing the XSLT command-line tool:
-
- // Obtain a reference to the translet class
- Class cls = Class.forName(transletName);
- // Instanciate a translet object (inherits AbstractTranslet)
- AbstractTranslet translet = (AbstractTranslet)cls.newInstance();
-
- // Prepare the internal DOM tree
- final DOMImpl dom = new DOMImpl();
- dom.setDocumentURI(inputURI);
-
- // Create a parser for the input document
- final Parser parser = new Parser();
- parser.setDocumentHandler(dom.getBuilder());
-
- // Create a DTDMonitor for handling ID references in the DTD
- DTDMonitor dtdMonitor = new DTDMonitor();
- parser.setDTDHandler(dtdMonitor);
- // Create output handler (you can plug in your own)
- DefaultSAXOutputHandler saxHandler;
- saxHandler = new DefaultSAXOutputHandler(out);
-
- // Parse the document and build the internal DOM
- parser.parse(inputURI);
-
- // Pass information on id/key indicies to the translet
- translet.setIndexSize(dom.getSize());
- dtdMonitor.buildIdIndex(dom, 0, translet);
- translet.setUnparsedEntityURIs(dtdMonitor.getUnparsedEntityURIs());
-
- // Start the transformation
- translet.transform(dom, new TextOutput(saxHandler));
+This file contains a minimal implementation of an XSL transformation
+servlet. It utilizes a cache to store the DOM trees for frequently
+accessed XML documents. These are not W3C DOM objects; They are
+specialized DOMs, native to XSLTC and optimzed for use with compiled
+translets. In addition to the initial input XML documents, the cache
+may contain DOMs for other XML input documents the translet requires
+at runtime, when the xsl:document() function is used in the stylesheet.
-Alternatively the servlet can use a cache for storing
-frequently accessed XML documents. This is not only a matter
-of reading the initial input document from the cache, as
-the translet may load other XML input documents as runtime.
-(If the xsl:document() function was used in the stylesheet.)
+Here's the essential code in the servlet for doing the transformation:
// Get a reference to the translet class
Class cls = Class.forName(transletName);
@@ -71,7 +41,8 @@
// in needs to load additional XML documents.
translet.setDOMCache(cache);
- // Get the DOM from the DOM cache
+ // Get the DOM from the DOM cache if current, otherwise
+ // build and cache the DOM first
DOMImpl dom = cache.retrieveDocument(documentURI, 0, translet);
// Create output handler (you can plug in your own)
@@ -81,7 +52,7 @@
// Start the transformation
translet.transform(dom, new TextOutput(saxHandler));
-------------------------------------------------------------
+-----------------------------------------------------------------------
BUILDING YOUR OWN DOM CACHE
The interface for the DOM cache consists of a single method,
@@ -103,15 +74,18 @@
// Instanciate a DOMImpl object
Parser parser = new Parser();
DOMImpl dom = new DOMImpl();
+ // Set URI for imports, includes, and document() functions
dom.setDocumentURI(uri);
- parser.setDocumentHandler(dom.getBuilder());
+ parser = factory.newSAXParser();
+ reader = parser.getXMLReader();
+ reader.setContentHandler(dom.getBuilder());
// Use a DTDMonitor to track ID references in DTD
DTDMonitor dtdMonitor = new DTDMonitor();
- parser.setDTDHandler(dtdMonitor);
+ dtdMonitor.handleDTD(reader);
// Parse the input document and build DOM
- parser.parse(uri);
+ reader.parse(uri);
At this point the DOMImpl and DTDMonitor objects are
populated with the necessary data. The two objects
@@ -124,7 +98,7 @@
translet.setIndexSize(dom.getSize());
// Build indices for this DOM's DTD's ID references
- dtd.buildIdIndex(dom, mask, translet);
+ dtdMonitor.buildIdIndex(dom, mask, translet);
// Pass unparsed entity URIs to the translet
translet.setUnparsedEntityURIs(dtd.getUnparsedEntityURIs());
@@ -138,6 +112,59 @@
algorithm:
org/apache/xalan/xsltc/dom/DocumentCache.java
+
+-----------------------------------------------------------------------
+DOING TRANSFORMATIONS WITHOUT A DOM CACHE
+
+Alternatively, you can program a servlet to perform the same basic
+steps as the XSLTC command-line tool
+
+ org.apache.xalan.xsltc.cmdline.Transform
+
+as follows:
+
+
+ // Obtain a reference to the translet class
+ Class cls = Class.forName(transletName);
+ // Instanciate a translet object (inherits AbstractTranslet)
+ AbstractTranslet translet = (AbstractTranslet)cls.newInstance();
+
+ // Prepare the internal DOM tree
+ final DOMImpl dom = new DOMImpl();
+ dom.setDocumentURI(inputURI);
+
+ // Create a parser for the input document
+ // org.apache.xalan.xsltc.runtime.Constants sets NAMESPACE_FEATURE
+ final SAXParserFactory facory = SAXFactory.newInstance();
+ try {
+ factory.setFeature(NAMESPACE_FEATURE,true);
+ }
+ catch (Exception e) {
+ factory.setNamespaceAware(true);
+ }
+ parser = factory.newSAXParser();
+ reader = parser.getXMLReader();
+ reader.setContentHandler(dom.getBuilder());
+
+ // Create a DTDMonitor for handling ID references in the DTD
+ DTDMonitor dtdMonitor = new DTDMonitor();
+ dtdMonitor.handleDTD(reader);
+
+ // Create output handler (you can plug in your own)
+ DefaultSAXOutputHandler saxHandler;
+ saxHandler = new DefaultSAXOutputHandler(out);
+
+ // Parse the document and build the internal DOM
+ reader.parse(inputURI);
+
+ // Pass information on id/key indicies to the translet
+ translet.setIndexSize(dom.getSize());
+ dtdMonitor.buildIdIndex(dom, 0, translet);
+ translet.setUnparsedEntityURIs(dtdMonitor.getUnparsedEntityURIs());
+
+ // Start the transformation
+ translet.transform(dom, new TextOutput(saxHandler));
+
------------------------------------------------------------
END OF README
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
