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From Matt <dromitl...@gmail.com>
Subject Re: [BUG?] Cannot Load User Class on Local Environment
Date Tue, 25 Apr 2017 20:38:38 GMT
Hi Stefan,

Check the code here:
https://gist.github.com/17d82ee7dd921a0d649574a361cc017d , the output is at
the bottom of the page.

Here are the results of the additional tests you mentioned:

1. I was able to instantiate an inner class (Test$Foo) inside the Ignite
closure, no problem with that
2. I tried implementing SourceFunction and SinkFunction in Test itself, I
was able to instantiate the class inside the Ignite closure
3. I'm not sure what you meant in this point, is it something like what I
tried in line #56?

Additionally, I tried implementing the SourceFunction and SinkFunction in
Test$Foo with the same result: it says "Cannot load user class:

Looks like Flink is not using the correct ClassLoader. Any idea?


On Tue, Apr 25, 2017 at 7:00 AM, Stefan Richter <s.richter@data-artisans.com
> wrote:

> Hi,
> I would expect that the local environment picks up the class path from the
> code that launched it. So I think the question is what happens behind the
> scenes when you call ignite.compute().broadcast(runnable); . Which
> classes are shipped and how is the classpath build in the environment that
> runs the code. Your example is also not fully conclusive, because
> com.myproj.Test (which you can successfully instantiate) and
> com.myproj.Test$1$2 (which fails) are different classes, so maybe only the
> outer class is shipped with the broadcast call. My theory is that not all
> classes are shipped (e.g. inner classes), but only Test . You could try
> three things to analyze to problem a little more:
> 1) Create another inner class inside Test and try if you are still able to
> instantiate also this class via reflection.
> 2) Let Test class itself implement the map function (avoiding the usage of
> other/inner classes) and see if this works.
> 3) Check and set the thread’s context classloader inside the runnable to
> something that contains all required classes and see if this gets picked up
> by Flink.
> Best,
> Stefan
> Am 25.04.2017 um 07:27 schrieb Matt <dromitlabs@gmail.com>:
> Hi all,
> I'm trying to run Flink using a local environment, but on an Ignite node
> to achieve collocation (as mentioned in my previous message on this list).
> Have a look at the code in [1]. It's pretty simple, but I'm getting a
> "cannot load user class" error as shown in [2].
> If you check line #29 on the code, I'm able to create an instance of class
> Test, and it's the same context from which I'm creating the Flink job.
> Shouldn't it work provided I'm using a local environment?
> It would be really nice to be able to inject a ClassLoader into the chunk
> of code that creates the job. Is this currently possible?
> Any fix or workaround is appreciated!
> Best,
> Matt
> [1] https://gist.github.com/f248187b9638023b95ba8bd9d7f06215
> [2] https://gist.github.com/796ee05425535ece1736df7b1e884cce

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