RFR(S): 8167493: Test that JFR event can be retransformed by an agent

[Erik Gahlin]

Hi Misha,

I think this tests things as they should but I'm not 100% sure. It may 
make sense to change the flow a bit so it becomes more explicit. if you 
only does this in premain.

public static void premain(String args, Instrumentation inst) throws 
Exception {
    instrumentation = inst;
}

then in main:

1. TestEvent event = new TestEvent(); // loads class and run empty 
constructor
2. instrumentation.addTransformer(new TestClassFileTransformer());
3. instrumentation.retransformClasses(TestEvent.class);
4. TestEvent event = new TestEvent(); // instrumented constructor
5. Asserts.assertTrue(InstrumentationEventCallback.wasCalled());
6. InstrumentationEventCallback.clear();
7. Recording r = new Recording(); r.enable(TestEvent.class); r.start();
8. TestEvent event = new TestEvent(); event.commit(); // JFR 
instrumented commit
9. Asserts.assertTrue(InstrumentationEventCallback.wasCalled());
10. r.dump(file)
11. Asserts.assertTrue(!RecordingFile.readAllEvents().isEmpty())

Thanks
Erik

On 2020-02-13 17:12, mikhailo.seledtsov at oracle.com wrote:

> Please review this change that adds a new test to verify that a 
> user-defined JFR event can be tramsformed by an agent.
> This test uses a class transformer to add a callback into the <init> 
> of the event class, generates/records the event,
> and verifies that the added instrumentation callback was actually called.
>
> Also, the JavaAgentBuilder testlib utility was extended to accept 
> additional manifest attributes.
>
>     JBS: https://bugs.openjdk.java.net/browse/JDK-8167493
>     Webrev: http://cr.openjdk.java.net/~mseledtsov/8167493.02/
>     Testing:
>         1. Ran the newly created test: PASS
>         2. Ran all tests using JavaAgentBuilder: PASS
>
>
> Thank you,
> Misha
>