[
https://issues.apache.org/jira/browse/XALANJ-2589?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14091055#comment-14091055
]
Gary Gregory commented on XALANJ-2589:
--------------------------------------
Hello,
Could you please provide code changes in unified diff format (aka a patch file).
Gary
> ObjectFactory is reloading classes over-and-over causing performance issues
> with XPATH.
> ---------------------------------------------------------------------------------------
>
> Key: XALANJ-2589
> URL: https://issues.apache.org/jira/browse/XALANJ-2589
> Project: XalanJ2
> Issue Type: Bug
> Security Level: No security risk; visible to anyone(Ordinary problems in
> Xalan projects. Anybody can view the issue.)
> Affects Versions: 2.7.2
> Environment: Glassfish 3.1 with JDK 1.6 u37
> Reporter: brian yoder
> Assignee: Steven J. Hathaway
>
> I have done some performance benchmarking on XPath, and found that the
> ObjectFactory kept calling findProviderClass, which has code that is calling
> the following:
> providerClass = cl.loadClass(className);
> This is VERY inefficient, and is causing a severe bottleneck. If i comment
> this code out, and instead use the following I see a significant performance
> improvement.
> Class providerClass = Class.forName(className);
> I am running on Glassfish 3.1 - and the bottlneck is really bad because my
> JAR files were on SAN, so this code is running very slow.
> // Here is the code which I commented out, and rely ONLY on the Class.forName
> method. Not sure why the other stuff is needed, maybe only to support older
> JVM's?
> /**
> * Find a Class using the specified ClassLoader
> */
> static Class findProviderClass(String className, ClassLoader cl,
> boolean doFallback)
> throws ClassNotFoundException, ConfigurationError
> {
> //throw security exception if the calling thread is not allowed to
> access the
> //class. Restrict the access to the package classes as specified in
> java.security policy.
> SecurityManager security = System.getSecurityManager();
> try{
> if (security != null){
> final int lastDot = className.lastIndexOf('.');
> String packageName = className;
> if (lastDot != -1) packageName = className.substring(0,
> lastDot);
> security.checkPackageAccess(packageName);
> }
> }catch(SecurityException e){
> throw e;
> }
>
> Class providerClass = Class.forName(className);
> /*
> if (cl == null) {
> // XXX Use the bootstrap ClassLoader. There is no way to
> // load a class using the bootstrap ClassLoader that works
> // in both JDK 1.1 and Java 2. However, this should still
> // work b/c the following should be true:
> //
> // (cl == null) iff current ClassLoader == null
> //
> // Thus Class.forName(String) will use the current
> // ClassLoader which will be the bootstrap ClassLoader.
> providerClass = Class.forName(className);
> } else {
> try {
> providerClass = cl.loadClass(className);
> } catch (ClassNotFoundException x) {
> if (doFallback) {
> // Fall back to current classloader
> ClassLoader current =
> ObjectFactory.class.getClassLoader();
> if (current == null) {
> providerClass = Class.forName(className);
> } else if (cl != current) {
> cl = current;
> providerClass = cl.loadClass(className);
> } else {
> throw x;
> }
> } else {
> throw x;
> }
> }
> }
> */
> return providerClass;
> }
--
This message was sent by Atlassian JIRA
(v6.2#6252)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
