Yep -- I can use the same WAR in both cases, and it's a .class file in the
WAR.
I've also just figured out that if I rename the attribute from "class1" to
"cl1", it works -- so it's something to do with the attribute name matching
the class name.
On Mon, Feb 7, 2022 at 5:05 PM Rob Sargent <rsarg...@xmission.com> wrote:
>
>
> On 2/7/22 14:50, Robert Turner wrote:
> > All
> >
> > I'm hoping that someone can point me in the right direction as this issue
> > has been baffling me all day, and I'm starting to run out of ideas of
> what
> > to look at next.
> >
> > The logic below is working without issue until I move our test
> environment
> > into a Docker container. I'm using the same Tomcat version, and the same
> > JDK in both the container and the non-container environments.
> >
> >
> > I've got some EL in a JSP page, for example (simplified):
> >
> > <p>${class1.field}</p>
> >
> >
> > And an attribute is set on the page context as follows:
> >
> > final package1.Class1 objectValue = ...; // either value object of Class1
> > or null
> > pageContext.setAttribute("class1", objectValue);
> >
> >
> > Now, when objectValue is pointing to a valid object, everything is okay.
> > But when objectValue is null, this is where things get peculiar (and I
> get
> > both a working and non-working behaviour in the different environments).
> >
> > I can easily work around the issue by changing the EL to:
> >
> > <p>${not empty class1 ? class1.field : ''$}</p>
> >
> > But it is my understanding that EL should handle nulls on it's own, and
> > this shouldn't be necessary.
> >
> >
> > In the failure situation in the docker container, I'm seeing a
> > NoClassDefFoundError exception for "package1/Class1" below [1] during the
> > JSP page "rendering". Things work fine outside the docker container.
> >
> >
> > It might be worth noting that in my case, the attribute name is of the
> same
> > name as the actual class (with the first letter being lowercase for the
> > attribute instead of uppercase in the class).
> >
> > Note that I've also replaced my actual package name and class names with
> > "package1" and "Class1", and the attribute name with "class", but they
> > translate 1-to-1 as in what I've provided here and do not use reserved
> > names.
> >
> >
> > I've done a bit of digging into the EL scope resolution code in Tomcat,
> and
> > I'm suspecting it might be related to how it chooses the scope of the
> > object. Possibly related to maybe looking for static aspects of the
> class,
> > or something like that. After reviewing the Servlet / JSP / EL
> > documentation, I also haven't found anything obvious that would suggest
> > what the problem might be.
> >
> > Hopefully someone has encountered this before and can nudge me in the
> right
> > direction.
> >
> > Thanks in advance,
> >
> > Robert
> >
> >
> >
> > [1]
> > Caused by: java.lang.NoClassDefFoundError: package1/Class1 (wrong name:
> > package1/class1)
> > at java.base/java.lang.ClassLoader.defineClass1(Native Method)
> > at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1017)
> > at
> >
> java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:174)
> > at
> >
> org.apache.catalina.loader.WebappClassLoaderBase.findClassInternal(WebappClassLoaderBase.java:2478)
> > at
> >
> org.apache.catalina.loader.WebappClassLoaderBase.findClass(WebappClassLoaderBase.java:870)
> > at
> >
> org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1371)
> > at
> >
> org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1215)
> > at javax.el.ImportHandler.findClass(ImportHandler.java:477)
> > at javax.el.ImportHandler.resolveClass(ImportHandler.java:421)
> > at
> >
> javax.servlet.jsp.el.ScopedAttributeELResolver.getValue(ScopedAttributeELResolver.java:85)
> > at
> org.apache.jasper.el.JasperELResolver.getValue(JasperELResolver.java:124)
> > at org.apache.el.parser.AstIdentifier.getValue(AstIdentifier.java:93)
> > at org.apache.el.parser.AstValue.getValue(AstValue.java:136)
> > at org.apache.el.parser.AstFunction.getValue(AstFunction.java:188)
> > at
> org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:189)
> > at
> >
> org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:692)
> > at
> >
> And you're sure package1 is on the classpath of the docker version?
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
> For additional commands, e-mail: users-h...@tomcat.apache.org
>
>
