xref: /external/jacoco

We build an equivalent of the jacoco-agent.jar which contains classes from org.jacoco.core,
org.jacoco.agent and org.jacoco.agent.rt packages but also classes from asm 5.0.1.

However, Jacoco depends on classes that do not exist in Android (java.lang.instrument.* or
javax.management.*) for runtime instrumentation only. The ART compiler would reject those classes
when they are either in the bootclasspath (core, frameworks, ...) or system apps.

Since we only use offline instrumentation for code coverage (using Jack) and do not execute these
classes at runtime, we simply not compile them here.

We also need to modify the source code to cut dependencies to the classes that we exclude from the
compilation. The changes are surrounded by "BEGIN android-change" and "END android-change". Here
is the list of the changes:

1) Remove the creation of JmxRegistration in org.jacoco.agent.rt.internal.Agent.
2) Change default OutputMode to none in org.jacoco.core.runtime.AgentOptions
3) Change the runtime to reduce dependencies on core libraries.
   Previously, Offline's static initializer would eagerly create an
   Agent, a process which has lots of dependencies. With this change,
   Offline only eagerly creates a Map<Long, ExecutionData>, which is much
   more lightweight. The Agent is only created when it's actually
   needed. This makes it possible to instrument a lot of more core
   libraries without creating a circular dependency at runtime.