Fix FormAuthenticator corrupting post parameters.

[albfernandez]

Fixes #2318

[albfernandez]

I've provided a small test application #2318.

I would like to provide a JUnit test case but I'm having troubles setting up "environment" (I don't know how to setup Globals.setDefaultHabitat in a test envirnoment)

[Cousjava]

jenkins test please

[arjantijms]

Hi, thanks for discovering and reporting this! Before we can accept the PR you must have signed the CLA, or did you already sign it?

As for the test; since one of the parameters will be corrupted, I guess it will show as corrupted just as well in a regular Servlet application, right?

The easiest way for us to test that it's broken in version X and really fixed in X+1 is by means of the Java EE 7 samples test. In this case, it looks like it's only an extra test method in the existing test here: https://github.com/javaee-samples/javaee7-samples/tree/master/servlet/security-form-based

Would be ace if you could do a PR at that repo too with the test demonstrating the issue. Thanks in advance!

[payara-ci]

Quick build and test passed!

[albfernandez]

CLA signed and submitted.

I'll make the pull request to javaee7-sameples with the test case.

[albfernandez]

I've tried to reproduce the bug in javaee7-samples, but I've got a working test working fine: without the bug.

I've commited my work to my forked repo:

https://github.com/albfernandez/javaee7-samples/tree/formbased_authentication_corrupts_post_params_payara/servlet/security-form-based

I'll continue investigating next week.

[albfernandez]

I've finally "fixed" the test and I've done the PR to javaee7-samples repository

javaee-samples/javaee7-samples#429

[arjantijms]

@albfernandez thx a lot!