[Bug 1578] New: Applet which mixes jar file and class file throws java.lang.LinkageError

[bugzilla-daemon at icedtea.classpath.org]

http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=1578

            Bug ID: 1578
           Summary: Applet which mixes jar file and class file throws
                    java.lang.LinkageError
    Classification: Unclassified
           Product: IcedTea-Web
           Version: 1.3.2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P3
         Component: Plugin
          Assignee: dbhole at redhat.com
          Reporter: pico-icedtea-2af85mds at picomancer.com
                CC: unassigned at icedtea.classpath.org

I'm not sure if this is the right place to file this.  I'm not even sure that
this is a bug and not intended behavior.

I have an applet.  Some of the code I want my applet to run is in .class files.
 Why I can't put them in a jar file is a very long story [1], and not important
to the bug report.

What's important is that I'm using a jar file and a class file in the same
applet.  The applet source is available at
https://github.com/picomancer/icedtea-bugs

I dynamically load the class file with Class.forName() and call it with the
reflection API.  Both the class file and the applet file access a third class
in the jar file, the "API class" Printer in my example (i.e., an API for the
class file to communicate with the rest of the applet).  This causes the applet
to produce a LinkageError on stderr (I had to enable logging in IcedTea control
panel and look at $HOME/.icedtea/log/java.stderr).

I am using Linux Mint 15, an OS based on Ubuntu Raring Ringtail.  I have tried
with my OS's included versions of Firefox and Chromium; the bug is present in
both, which leads me to believe it's unlikely to be a browser problem.  The
openjdk-7-jre package is version 7u25-2.3.10-1ubuntu0.13.04.2.  The icedtea
plugin is listed as 1.3.2-1ubuntu1.1.

The application I was writing when I found this bug is 1000 lines long so far. 
Or maybe 3500, depending on how you count.  So instead, I wrote a small test
case that reproduces the behavior and put it on Github, linked above.

To any IcedTea developer reading this, please run this in IcedTea 3.2 and see
if you can reproduce the LinkageError.  Then run it again in IcedTea current
development version and see if anybody's fixed it.  If it hasn't been fixed
yet, please fix it for the next version.  Thanks!

[1] The short version:  I want to dynamically generate the class file on the
server while the applet is running, in response to a POST request by the applet
containing user input.  Two facts:  (A) Class files are only loaded when
they're referenced, and (B) You can dynamically reference classes with
Class.forName().  I'm trying to combine (A) and (B) to convince the plugin to
load classes that didn't exist when the applet started.  This footnote DOES NOT
apply to the github I linked; that example builds everything ahead of time with
Ant.  But this is the actual problem I was trying to solve when I triggered the
bug.  And I wanted to explain why the obvious solution of "put the loose class
file in the jar file with all your other class files" isn't a practical answer
for my use case; I'd welcome other suggestions/workarounds!

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