Custom checks broken with Checkstyle 8.0

[lkoe]

Please note this bug against eclipse-cs-8.0.0, which I believe to be an issue in Checkstyle core introduced somewhere after 7.6 (confirmed in 8.0):
https://sourceforge.net/p/eclipse-cs/discussion/274377/thread/4ab4f095/?limit=25#1334

Due to a "recent" change to PackageNamesLoader (supposedly this commit ddeb553) the class name guessing algorithm based on checkstyle_packages.xml files is not working properly anymore.
Please note the missing dot between package name and class name in the error message:

Caused by: com.puppycrawl.tools.checkstyle.api.CheckstyleException: Unable to instantiate 'Jsr305Annotations' class, it is also not possible to instantiate it as com.puppycrawl.tools.checkstyle.checks.annotationJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.blocksJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.codingJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.designJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.headerJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.importsJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.indentationJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.javadocJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.metricsJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.modifierJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.namingJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.regexpJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.sizesJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.whitespaceJsr305Annotations, com.puppycrawl.tools.checkstyle.checksJsr305Annotations, com.puppycrawl.tools.checkstyle.filefiltersJsr305Annotations, com.puppycrawl.tools.checkstyle.filtersJsr305Annotations, com.puppycrawl.tools.checkstyle.Jsr305Annotations, Jsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.annotationJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.blocksJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.codingJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.designJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.headerJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.importsJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.indentationJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.javadocJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.metricsJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.modifierJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.namingJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.regexpJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.sizesJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.whitespaceJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checksJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.filefiltersJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.filtersJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.Jsr305AnnotationsCheck. Please recheck that class name is specified as canonical name or read how to configure short name usage http://checkstyle.sourceforge.net/config.html#Packages. Please also recheck that provided ClassLoader to Checker is configured correctly.

[rnveach]

@lkoe Please provide us information to reproduce problem like check source, and how you are calling Checkstyle with it.
See http://checkstyle.sourceforge.net/report_issue.html#How_to_report_a_bug

[rnveach]

Please note the missing dot between package name and class name in the error message
com.puppycrawl.tools.checkstyle.checks.annotationJsr305Annotations

I missed this when reading the issue before.
I can reproduce the issue with the current release and CLI.

$ cat TestClass.java
public class TestClass {
    void method() {
    }
}

$ cat TestConfig.xml
<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
          "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
          "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">

<module name="Checker">
    <property name="charset" value="UTF-8"/>

    <module name="TreeWalker">
<module name="Jsr305Annotations" />
    </module>
</module>

$ java -jar checkstyle-8.1-all.jar -c TestConfig.xml TestClass.java
com.puppycrawl.tools.checkstyle.api.CheckstyleException: cannot initialize module TreeWalker - Unable to instantiate 'Jsr305Annotations' class, it is also not possible to instantiate it as com.puppycrawl.tools.checkstyle.checks.annotationJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.blocksJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.codingJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.designJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.headerJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.importsJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.indentationJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.javadocJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.metricsJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.modifierJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.namingJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.regexpJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.sizesJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.whitespaceJsr305Annotations, com.puppycrawl.tools.checkstyle.checksJsr305Annotations, com.puppycrawl.tools.checkstyle.filefiltersJsr305Annotations, com.puppycrawl.tools.checkstyle.filtersJsr305Annotations, com.puppycrawl.tools.checkstyle.Jsr305Annotations, Jsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.annotationJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.blocksJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.codingJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.designJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.headerJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.importsJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.indentationJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.javadocJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.metricsJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.modifierJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.namingJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.regexpJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.sizesJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.whitespaceJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checksJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.filefiltersJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.filtersJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.Jsr305AnnotationsCheck. Please recheck that class name is specified as canonical name or read how to configure short name usage http://checkstyle.sourceforge.net/config.html#Packages. Please also recheck that provided ClassLoader to Checker is configured correctly.
    at com.puppycrawl.tools.checkstyle.Checker.setupChild(Checker.java:461)
    at com.puppycrawl.tools.checkstyle.api.AutomaticBean.configure(AutomaticBean.java:171)
    at com.puppycrawl.tools.checkstyle.Main.runCheckstyle(Main.java:504)
    at com.puppycrawl.tools.checkstyle.Main.runCli(Main.java:431)
    at com.puppycrawl.tools.checkstyle.Main.main(Main.java:209)
Caused by: com.puppycrawl.tools.checkstyle.api.CheckstyleException: Unable to instantiate 'Jsr305Annotations' class, it is also not possible to instantiate it as com.puppycrawl.tools.checkstyle.checks.annotationJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.blocksJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.codingJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.designJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.headerJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.importsJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.indentationJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.javadocJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.metricsJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.modifierJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.namingJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.regexpJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.sizesJsr305Annotations, com.puppycrawl.tools.checkstyle.checks.whitespaceJsr305Annotations, com.puppycrawl.tools.checkstyle.checksJsr305Annotations, com.puppycrawl.tools.checkstyle.filefiltersJsr305Annotations, com.puppycrawl.tools.checkstyle.filtersJsr305Annotations, com.puppycrawl.tools.checkstyle.Jsr305Annotations, Jsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.annotationJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.blocksJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.codingJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.designJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.headerJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.importsJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.indentationJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.javadocJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.metricsJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.modifierJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.namingJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.regexpJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.sizesJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checks.whitespaceJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.checksJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.filefiltersJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.filtersJsr305AnnotationsCheck, com.puppycrawl.tools.checkstyle.Jsr305AnnotationsCheck. Please recheck that class name is specified as canonical name or read how to configure short name usage http://checkstyle.sourceforge.net/config.html#Packages. Please also recheck that provided ClassLoader to Checker is configured correctly.
    at com.puppycrawl.tools.checkstyle.PackageObjectFactory.createModule(PackageObjectFactory.java:184)
    at com.puppycrawl.tools.checkstyle.TreeWalker.setupChild(TreeWalker.java:168)
    at com.puppycrawl.tools.checkstyle.api.AutomaticBean.configure(AutomaticBean.java:171)
    at com.puppycrawl.tools.checkstyle.Checker.setupChild(Checker.java:456)
    ... 4 more
Checkstyle ends with 1 errors.

com.puppycrawl.tools.checkstyle.checks.annotationJsr305Annotations

I can't reproduce this issue in our tests. The ones I have looked at have the periods, so I am not sure why the jar is not showing them. The nightly jar produces the same result as the release.

[rnveach]

Looking at the end of the error displayed is:

com.puppycrawl.tools.checkstyle.Jsr305AnnotationsCheck

I can produce the invalid display with modifying the test PackageObjectFactoryTest.testCreateObjectFromFullModuleNamesWithException

@lkoe List of tried results may just be a display problem, and not a result of failing to load the check. We still need your details to determine why your check won't load if it is defined correctly.

[romani]

fix for correct message print is provided.
We still need more details on class location to prove that it can not be loaded but it present in classpath.

[bjrke]

As maintainer of Jsr305Annotations I can confirm that the current master of the plugin is able to run against checkstyle 8 as seen in the tests https://travis-ci.org/bjrke/JSR305CheckstylePlugin.
Dispite https://github.com/bjrke/JSR305CheckstylePlugin/releases/download/0.5.0/JSR305CheckstylePlugin-0.5.0.jar is not working since it still uses the deprecated and in 8 removed base class Checks which is fixed by bjrke/JSR305CheckstylePlugin@e5fdf3c.
But I didn't released yet because eclipse-cs is not working.

Anyway, the class names in output pasted by @lkoe was generated by me in the eclipse-cs environment.

[romani]

ok , I am closing this issue for now, if some other problems found it could be reopened or it is better to create new issue.