Conflicts with JaCoCo

[kongy...@gmail.com]

Hi,

Here is a situation.

I develop another java agent which used to instrument some byte code to record some log information.

Then I also want to use JaCoCo to calculate the coverage about original java code.

Is there any conflict between these java agents?

Does JaCoCo has some function that rollback the byte code which is redefined by another java agent?

Thanks!

-- Kevin Kong

[Evgeny Mandrikov]

Hi,

I don't think that there is a way for one class transformer to rollback modifications done by another class transformer in general without exact knowledge of the performed transformation. Thus there is no such function in JaCoCo: its changes are always done on top of changes done by previous transformers - as per https://docs.oracle.com/javase/7/docs/api/java/lang/instrument/ClassFileTransformer.html "transformers are called in the order registered".

So to make sure that you'll be able generate coverage report - specify JaCoCo agent before your agent in command line ( see "What workarounds exist to deal with runtime-modified classes?" http://www.eclemma.org/jacoco/trunk/doc/classids.html ). This way JaCoCo will see original classes and your agent will see classes instrumented by JaCoCo.

Hope this helps.