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xsltwebsphere-libertyjaxp

Websphere Liberty seems to override System Property TransformerFactory set via jvm.options

I am trying to migrate a legacy app that is using camel/cxf (offers some web services that include transformations) to Websphere Liberty 16.0.0.03 (IBM JRE 1.8). Tests are failing because the app uses extensions functions. I tried to disable secure processing as described here.

This change has no effect. That's why I try to switch to Saxon Implementation globally by setting System Property "javax.xml.transform.TransformerFactory=net.sf.saxon.TransformerFactoryImpl" in jvm.options config file. Again - this does not work.

While debugging I can see, that com.ibm.ws.webcontainer.osgi.mbeans.PluginGenerator$2 is overriding the Property with com.ibm.xtq.xslt.jaxp.compiler.TransformerFactoryImpl during Server start. I can see a method "PluginGenerator.revertTransformerFactoryIfNeccessary" in the stack that seems to trigger the change. Afterwards all FactoryFinder.find() will return the non-Saxon implementation.

Can anyone suggest how to either disable secure-processing successfully

or

a way to successfully set a custom TransformerFactory?

BTW: It seems to me like these 2 are bugs - do I report these as regular PMR?

EDIT: possible workaround

As result of the helpful suggestions I added an '@WebListener' that will sets the System Property within the constructor (setting it in contextInitialized is too late as stylesheets seem to be compiled during application start and thus processing fails tests). I bundle this a "patch-jar" with the legacy app.

Solution

  • The Liberty web container plugin generator will only override the xml transformer factory if the IBM JDK is being used.

    While the web container performs plugin generation using the IBM JDK, it will swap to an alternate transformer factory, and then reset to the IBM JDK default of which is com.ibm.xtq.xslt.jaxp.compiler.TransformerFactoryImpl.

    I think it is worth opening a PMR here. The PluginGenerator should not assume that it started with the default xml transformer factory, and should instead save off the value of javax.xml.transform.TransformerFactory and then restore it after plugin generation has completed.

    Temp workaround:
    Since the PluginGenerator only swaps the XML transformer factory if you're running on the IBM JDK, you could change to an alternate JDK until your PMR gets resolved.