[java] JavaRuleViolation loses information in className field when class has package-private access level

[KroArtem]

Affects PMD Version: 6.12

Rule: e.g UnusedUmportsRule

Description:
UnusedImportsRule warns about unused imports. When it founds an unused import, it adds it to a Set<ImportWrapper> imports and then adds violation. JavaRuleViolation has method setClassNameFrom, which (I believe) has the root of the problem.

Code Sample demonstrating the issue:

Here is this method that has the problem. If the class has default (package-private) access level, qualifiedName and className both remain null.

    private void setClassNameFrom(JavaNode node) {
        String qualifiedName = null;
        for (AbstractAnyTypeDeclaration parent : node.getParentsOfType(AbstractAnyTypeDeclaration.class)) {
            String clsName = parent.getScope().getEnclosingScope(ClassScope.class).getClassName();
            if (qualifiedName == null) {
                qualifiedName = clsName;
            } else {
                qualifiedName = clsName + '$' + qualifiedName;
            }
        }

        if (qualifiedName == null) {
            Set<ClassNameDeclaration> classes = node.getScope().getEnclosingScope(SourceFileScope.class)
                    .getClassDeclarations().keySet();
            for (ClassNameDeclaration c : classes) {
                // find the first public class/enum declaration
                if (c.getAccessNodeParent() instanceof AccessNode) {
                    if (((AccessNode) c.getAccessNodeParent()).isPublic()) {
                        qualifiedName = c.getImage();
                        break;
                    }
                }
            }
        }

        if (qualifiedName != null) {
            className = qualifiedName;
        }

Running PMD through: Other

[jsotuyod]

@KroArtem thanks for the report! You are absolutely right about this, and you analysis was spot on.

I did however struggle a little understanding the issue at first. Having a code snippet + the generated report would have been a great aid.

[KroArtem]

@jsotuyod , hello! Actually I was more or less ready to provide more info if only anybody asked for it. We're using PMD not as a maven goal but as a test that checks only changed files comparing to master. That's why I didn't have any report.

Next time I'd be glad to ask for more info and probably fix something by myself, though I wasn't sure where is the active developers' place (slack, irc or whatever). Now I see you're using sourceforge

[jsotuyod]

@KroArtem don't worry, I'm looking forward for any contributions from you! We are on fitter. Check the Readme for a link.