[FLINK-2275] Migrate test from package 'org.apache.flink.test.javaApiOperators'

[mjsax]

migrated test from execute() to collect()
subtask of https://issues.apache.org/jira/browse/FLINK-2032

[mjsax]

I adapted all tests except for DataSinkITCase and ExecutionEnvironmentITCase.

• DataSinkITCase -> seems to test writing to file explicit; would not make sense to change it (tell me, if I am wrong)
• ExecutionEnvironmentITCase ->uses LocalCollectionOutputFormat, and is not writing to disc already

[StephanEwen]

All in all this looks good.

The only think that strikes me as odd is the test pattern (which was used also before the refactoring). I am not a big fan of validating results in an @After method. I find the tests more readable if they simply call the comparison themselves at the end:

List<Tuple2<String, Integer>> result = data.collect()

String expected = "Hello,2\n" + 
                  "Dude,5\n" 

compareResultAsTuples(expexted, result)

This also solves the issue with the raw type lists, which is usually an indicator that something is not modeled in the right way (unless you dynamically load or instantiate types).

[StephanEwen]

This comment is not a blocker for merging this. Let's just not write future tests like this, and whenever we touch something, we could on-the-fly migrate the tests to not follow this pattern any more...

[mjsax]

I agree. I just did not want to change the current pattern... However, we should do it the right way in this PR, too. I will update the code accordingly.

[mjsax]

Done. Failing tests revile a Kafka problem (in my Travis, too https://travis-ci.org/mjsax/flink/builds/68598571). Is it known? Module flink-tests passed in all runs.

Should be ready to get merged.

[rmetzger]

@gyfora re-enabled a disabled Kafka test in this pull request: https://github.com/apache/flink/pull/747/files
The test is known to be unstable, thats why I disabled it for the time being. Can you disable it again in your PR?

[gyfora]

Sorry about re-enabling the failing test, I completely missed it...
Matthias please @ignore it :P

Btw @rmetzger do we have a JIRA for this?

[mjsax]

Done. If Travis is green, please merge. :)

[StephanEwen]

Looks good, let me merge this...