RFR 8221857: Collect code coverage for a subset of code

Mon Apr 8 21:12:25 UTC 2019

Hi, 

Could you please take a look on this enhancement which makes it easy to get code coverage for a part of JDK code. 

This change introduces “JCOV_FILTERS” make variable and also "--with-jcov-filters” configuration option. 

With that one is free to use any of JCov filtering options to limit the resulting report to only the desired code. 

This is an excerpt from JCov usage output:

    Filtering conditions.
        -include(i) 'string value' (Option could be specified several times.)
        -exclude(e) 'string value' (Option could be specified several times.)
        -include_list 'string value'
        -exclude_list 'string value'
        -include_module_list 'string value'
        -exclude_module_list 'string value'
    Filtering conditions.
        -include_module(im) 'string value' (Option could be specified several times.)
        -exclude_module(em) 'string value' (Option could be specified several times.)
        -fm 'string value' (Option could be specified several times.)
        -fm_list 'string value'

Bug: https://bugs.openjdk.java.net/browse/JDK-8221857
Webrev: http://cr.openjdk.java.net/~shurailine/JDK-8221857/webrev.00/

Thank you.

Shura