dleslie 01/02/15 10:54:42
Modified: c/xdocs/sources/xalan faq.xml
Log:
Dave's rewrite on thread safety.
Revision Changes Path
1.15 +16 -12 xml-xalan/c/xdocs/sources/xalan/faq.xml
Index: faq.xml
===================================================================
RCS file: /home/cvs/xml-xalan/c/xdocs/sources/xalan/faq.xml,v
retrieving revision 1.14
retrieving revision 1.15
diff -u -r1.14 -r1.15
--- faq.xml 2001/02/15 17:39:58 1.14
+++ faq.xml 2001/02/15 18:54:37 1.15
@@ -127,21 +127,25 @@
</faq>
- <faq title="Are the XSLTEngineImpl (XSLT processor) and StylesheetRoot
(compiled stylesheet) objects thread-safe?">
+ <faq title="Is &xslt4c; thread-safe?">
- <q>Are the XSLTEngineImpl (XSLT processor) and StylesheetRoot (compiled
stylesheet) objects thread-safe?</q>
+ <q>Is &xslt4c; thread-safe?</q>
<a>
- <p>The XSLTEngineImpl stores running state information, so it is not
thread-safe. If you want to use the XSLTEngineImpl
- to perform multiple simultaneous transformations, create a separate
instance for each transformation.
- If you want to perform multiple serial transformations with a single
XSLTEngineImpl object, call the XSLTEngineImpl reset()
- method after each transformation. You may want to serialize access to
this object, so it can't accidentally start another
- transformation while a transformation is in progress.</p>
- <p>StylesheetRoot objects, on the other hand, are thread-safe. A single
StylesheetRoot object may be called concurrently
- from multiple threads. Keep in mind, however, that the StylesheetRoot
uses an XSLTEgineImpl to store running state
- information for each transformation, so you must call the XSLTEngineImpl
reset() method and the StylesheetExecutionDefault
- reset() method between each transformation.</p>
- <p>For more detail, see <link idref="samples"
anchor="compilestylesheet">CompileStylesheet</link>.</p></a>
+ <p>In order to support very efficient use in multi-threaded
applications, &xslt4c; is designed to avoid synchronization as much as
+ possible. Each thread of execution is required to have its own set of
"support" objects that contain the state of the
+ transformation. Accordingly, no synchronization is required when
multiple threads are executing.</p>
+
+ <p>Parsed ("compiled") stylesheets (see <link idref="usagepatterns"
anchor="compiled">Compiling stylesheets</link>) and parsed
+ source documents may be freely shared by multiple threads of execution
without worrying
+ about providing synchronized access to them. The ONLY exception to
this rule: You use XercesParserLiaison to parse a document after
+ calling XercesParserLiaison::setBuildBridgeNodes(false) or
XercesParserLiaison::setThreadSafe(false). In this case, the document
+ CANNOT be shared by multiple threads of execution. For reasons of
performance, we do not recommend the use of
+ XercesParserLiaison, so this should not be an issue for most
applications.</p>
+
+ <p>All other objects in &xslt4c; are NOT thread-safe. Each thread must
have its own instance of each object.</p>
+
+ <p>See the <link idref="samples" anchor="threadsafe">ThreadSafe</link>
sample program for more information.</p></a>
</faq>
<faq title="What can I do to speed up transformations?">
