How to supress checkstyle HideUtilityClassConstructor rule for classes with main method?

Question

I want to suppress 'HideUtilityClassConstructor' rule the for classes that have main method. That look like this:

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class Application {
   public static void main(String[] args) {
       SpringApplication.run(Application.class, args);
   }
}

Since all checkstyle rules are located in the common library - it should be a generic skip for any module that uses those rules.
Name of the main class can be different (the skip should be applied for all classes that have public static main method)
The change should be located in checkstyle common xml files (not in main class, like using @SupressWarnings or comments)

Is it possible to do it?

score 0 · Answer 1 · answered Jun 26 '21 at 01:32

You can achieve this with SuppressionXpathFilter. For example, for your code you need to add this module to your config (in this example suppressions are in file suppressions.xml)

<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
      "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
      "https://checkstyle.org/dtds/configuration_1_3.dtd">
<module name = "Checker">

    <module name="TreeWalker">
        <module name="SuppressionXpathFilter">
            <property name="file" value="suppressions.xml"/>
            <property name="optional" value="false"/>
        </module>
        <module name="HideUtilityClassConstructor"/>
    </module>
</module>

And content of suppressions.xml file is like this. Here are 2 suppressions, you can pick any of them. Second looks better to me since there can be less possible false-positives.

<?xml version="1.0"?>

<!DOCTYPE suppressions PUBLIC
"-//Checkstyle//DTD SuppressionXpathFilter Experimental Configuration 1.2//EN"
"https://checkstyle.org/dtds/suppressions_1_2_xpath_experimental.dtd">

<suppressions>
  <!--  Suppress for any classes that contain method named "main"  -->
  <suppress-xpath checks="HideUtilityClassConstructor"
  query="//CLASS_DEF[//METHOD_DEF[./IDENT[@text='main']]]"/>

  <!--  Suppress for any classes that are annotated with "SpringBootApplication"  -->
  <suppress-xpath checks="HideUtilityClassConstructor"
   query="//CLASS_DEF[//MODIFIERS/ANNOTATION[./IDENT[@text='SpringBootApplication']]]"/>

</suppressions>

How to supress checkstyle HideUtilityClassConstructor rule for classes with main method?

1 Answers1