How to avoid excessive output when positively checking method calls

[perlun]

Hi,

We have some code which roughly looks like this:

    private static final Set<String> WHITELISTED_MANAGER_CLASSES = ImmutableSet.of(
            SomeManager.class.getName(),
            SomeOtherManager.class.getName()
            // [...]
    );

    @Test
    void whitelisted_managers_call_SomeDBLayerClass_methods() {
        classes()
                .that( describe( "are declared in whitelisted manager classes", target -> WHITELISTED_MANAGER_CLASSES.contains( target.getName() ) ) )
                .should().callMethodWhere( target( is( declaredIn( SomeDBLayerClass.class ) ) ) )
                .check( classes );
    }

This works fine; this check ensures that all the listed Manager classes do indeed call into SomeDBLayerClass. However, when it fails, the output is very very verbose:

java.lang.AssertionError: Architecture Violation [Priority: MEDIUM] - Rule 'classes that are declared in whitelisted manager classes should call method where target is declared in some.package.name.server.database.SomeDBLayerClass' was violated (1 times):
Method <some.package.name.server.managers.SomeViolatingManager.doSomething(some.package.name.domain.SomeDomainObject)> calls method <some.package.name.server.database.MediaScheduleMediator.doSomething(some.package.name.domain.SomeDomainObject)> in (SomeViolatingManager.java:216)
Method <some.package.name.server.managers.SomeViolatingManager.doSomething(some.package.name.domain.SomeDomainObject)> calls method <some.package.name.server.managers.SomeViolatingManager.doSomethingElseToo()> in (SomeViolatingManager.java:218)
Method <some.package.name.server.managers.SomeViolatingManager.doSomething(some.package.name.domain.SomeDomainObject)> calls method <some.package.name.server.managers.SomeViolatingManager.doSomethingElseThree(some.package.name.domain.SomeDomainObject)> in (SomeViolatingManager.java:219)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <java.util.Iterator.next()> in (SomeViolatingManager.java:131)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <fi.hibox.lib.util.Pair.getSecond()> in (SomeViolatingManager.java:137)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <java.util.Set.iterator()> in (SomeViolatingManager.java:131)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <some.package.name.server.database.SomeOtherDBLayerClass.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> in (SomeViolatingManager.java:124)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <some.package.name.server.database.SomeOtherDBLayerClassToo.getSomeOtherData(int)> in (SomeViolatingManager.java:118)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <java.util.List.size()> in (SomeViolatingManager.java:151)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <java.util.Iterator.hasNext()> in (SomeViolatingManager.java:131)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <some.package.name.server.managers.SomeOtherManager.getSomeData(int)> in (SomeViolatingManager.java:154)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <com.google.common.collect.Lists.newArrayList()> in (SomeViolatingManager.java:130)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <java.util.Iterator.next()> in (SomeViolatingManager.java:152)
Method <some.package.name.server.managers.SomeViolatingManager.doSomethingElse(int, int, java.util.Set, java.util.Set, java.util.Set)> calls method <some.package.name.server.notification.NotificationFactory.reset()> in (SomeViolatingManager.java:156)
[...]

Is there any way to get rid of this? 🤔 Basically, it seems to log every single method call from these (whitelisted) classes in question. It would be enough to just log the class name in this case. I guess the ArchUnit reporter can be customized somehow?

(The reason for this test in the first place is to ensure that the whitelist is kept up-to-date. Whenever a Manager class no longer calls into SomeDBLayerClass, the idea is to force its removal from the whitelist.)

[nbrugger-tgm]

In this case it would help to reformulate the rule.
At the moment it probably looks something like this :
methods().that(you want to check) .should(notAccessYourList())
Therefore the violation is reported on a method level

I would try formulating it like this
classes().that(you want to check) .should(notHaveMethodsThat(accessYourList())
Of course this is very pseudo code but the base idea being to scan for bad classes rather tan bad methods therefore you would hopefully get violations lile

Class xyz has method ABC that calls your bad access predicate (xyz.java:123)

[perlun]

Thanks for the suggestions @nbrugger-tgm. You're probably right.

@codecholeric - any ideas on how to transform my current test (code below) to a form which would display the violations on class-level rather than method-level? 🤔

    @Test
    void whitelisted_managers_call_SomeDBLayerClass_methods() {
        classes()
                .that( describe( "are declared in whitelisted manager classes", target -> WHITELISTED_MANAGER_CLASSES.contains( target.getName() ) ) )
                .should().callMethodWhere( target( is( declaredIn( SomeDBLayerClass.class ) ) ) )
                .check( classes );
    }

[hankem]

I think you can achieve your goal with a custom ArchCondition:

// ...
.should(new ArchCondition<JavaClass>("call a method in SomeDBLayerClass") {
    @Override
    public void check(JavaClass javaClass, ConditionEvents conditionEvents) {
        if (javaClass.getMethodCallsFromSelf().stream().noneMatch(call -> call.getTargetOwner().isEquivalentTo(SomeDBLayerClass.class))) {
            conditionEvents.add(SimpleConditionEvent.violated(javaClass, javaClass.getName() + " does not call a method in SomeDBLayerClass"));
        }
    }
}) // ...

[perlun]

Thanks @hankem, this does the trick nicely. 🙏 🎉 Greatly appreciated!