Hi, Answer 1:
The method RuntimeData.equals() will be called. You find the implementation here: https://github.com/jacoco/jacoco/blob/master/org.jacoco.core/src/org/jacoco/core/runtime/RuntimeData.java#L161 Answer 2: Instrumented classes will call equals() on a instance of RuntimeData. There are different strategies to get access to a instance shared with the runtime. It is described in https://www.jacoco.org/jacoco/trunk/doc/implementation.html <https://www.jacoco.org/jacoco/trunk/doc/implementation.html> in section “Coverage Runtime Dependency”. We do this “magic” to avoid direct dependencies on JaCoCo classes from instrumented classes which will fail in situations where app classes are separated with a different class loader. Regards, -marc > On 21. Sep 2020, at 05:18, zhen da <dazhen5...@gmail.com> wrote: > > Thank your for your reply~ Recently I have been studied the original code. I > read the page " https://www.jacoco.org/jacoco/trunk/doc/implementation.html > <https://www.jacoco.org/jacoco/trunk/doc/implementation.html>" , but I > noticed the most tricky part is not shown in "Coverage RunTime Dependency" > section. I still confused about the equals method. > So Question 1 is: When the code "access.equals(args)" is executed, what > happenned on earth？Could you explain it in detail please? > > //begin > Object access = ... // Retrieve instance > > Object[] args = new Object[3]; > args[0] = Long.valueOf(8060044182221863588); // class id > args[1] = "com/example/MyClass"; // class name > args[2] = Integer.valueOf(24); // probe count > > access.equals(args); > boolean[] probes = (boolean[]) args[0]; > //end > > By the way, I found there is an equals method overridden in class > RuntimeData, but I couldn't find the place it called. I don't think it has > something to do with the call "access.equals(args);" , because the > variable "access" is not an instance fo RunTimeData. > So Question 2 is : Where and When will the RunTimeData.equals() method be > called? > > Regards, > > 在2020年9月15日星期二 UTC+8 上午3:43:03<Marc R. Hoffmann> 写道： > Hi, > > we use the equals method as an “API” to the JaCoCo runtime. See “Coverage > Runtime Dependency” here: > https://www.jacoco.org/jacoco/trunk/doc/implementation.html > <https://www.jacoco.org/jacoco/trunk/doc/implementation.html> > > Regards, > -marc > > > > > >> On 14. Sep 2020, at 16:22, zhen da <dazhe...@gmail.com >> <applewebdata://813F77BA-6F07-4C1A-8DE0-4A7F096B4082>> wrote: >> > >> https://www.jacoco.org/jacoco/trunk/doc/implementation.html >> <https://www.jacoco.org/jacoco/trunk/doc/implementation.html> >> I found the error occured because I deleted the codeline >> "UnknownError.$jacocoAccess.equals(arrobject);", but what happend behind the >> equals method? >> 在2020年9月14日星期一 UTC+8 下午10:05:54<zhen da> 写道： >> hey,guys~ >> >> I checked the generated probe code,which is the $jacocoInit$() method. >> private static /* synthetic */ boolean[] $jacocoInit() { >> boolean[] arrbl = $jacocoData; >> if ($jacocoData == null) { >> Object[] arrobject = new Object[]{-4939888610684879937L, >> "org/jacoco/examples/CoreTutorial$MemoryClassLoader", 6}; >> UnknownError.$jacocoAccess.equals(arrobject); >> arrbl = $jacocoData = (boolean[])arrobject[0]; >> } >> return arrbl; >> } >> >> When I saw the code >> arrbl = $jacocoData = (boolean[])arrobject[0]; >> >> I was really confused.Why a variable of type "long" can be cast to a boolean >> array type? So I did a test: >> public class TestJacocoInit { >> private static transient /* synthetic */ boolean[] $jacocoData; >> >> public static /* synthetic */ boolean[] $jacocoInit() { >> boolean[] arrbl = $jacocoData; >> if ($jacocoData == null) { >> Object[] arrobject = new Object[]{4824536285859479710L, >> "org/jacoco/examples/CoreTutorial$TestTarget", 6}; >> //UnknownError.$jacocoAccess.equals(arrobject); >> arrbl = $jacocoData = (boolean[])arrobject[0]; >> } >> return arrbl; >> } >> >> public static void main(String[] args){ >> $jacocoInit(); >> } >> } >> >> The program occured error when executed: >> >> objc[25273]: Class JavaLaunchHelper is implemented in both >> /Library/Java/JavaVirtualMachines/jdk1.8.0_151.jdk/Contents/Home/bin/java >> (0x10bd1e4c0) and >> /Library/Java/JavaVirtualMachines/jdk1.8.0_151.jdk/Contents/Home/jre/lib/libinstrument.dylib >> (0x10ddc04e0). One of the two will be used. Which one is undefined. >> Connected to the target VM, address: '127.0.0.1:54961 >> <http://127.0.0.1:54961/>', transport: 'socket' >> Exception in thread "main" java.lang.ClassCastException: java.lang.Long >> cannot be cast to [Z >> at >> org.jacoco.examples.TestJacocoInit.$jacocoInit(TestJacocoInit.java:16) >> at org.jacoco.examples.TestJacocoInit.main(TestJacocoInit.java:22) >> Disconnected from the target VM, address: '127.0.0.1:54961 >> <http://127.0.0.1:54961/>', transport: 'socket' >> >> >> >> Can somebody explain these jacoco generated codes? >> >> >> Thanks~ >> >> > >> -- >> You received this message because you are subscribed to the Google Groups >> "JaCoCo and EclEmma Users" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to jacoco+un...@googlegroups.com >> <applewebdata://813F77BA-6F07-4C1A-8DE0-4A7F096B4082>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/jacoco/2bceb343-d07c-4905-b8b8-71ff901acd93n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/jacoco/2bceb343-d07c-4905-b8b8-71ff901acd93n%40googlegroups.com?utm_medium=email&utm_source=footer>. > > > -- > You received this message because you are subscribed to the Google Groups > "JaCoCo and EclEmma Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to jacoco+unsubscr...@googlegroups.com > <mailto:jacoco+unsubscr...@googlegroups.com>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/jacoco/4a649ad1-188a-4164-8657-75f9bd23e1b5n%40googlegroups.com > > <https://groups.google.com/d/msgid/jacoco/4a649ad1-188a-4164-8657-75f9bd23e1b5n%40googlegroups.com?utm_medium=email&utm_source=footer>. -- You received this message because you are subscribed to the Google Groups "JaCoCo and EclEmma Users" group. 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