File filter BeforeExecutionExclusionFileFilter decides which files should be excluded from being processed by the utility.
By default Checkstyle includes all files and sub-directories in a directory to be processed and checked for violations. Users could have files that are in these sub-directories that shouldn't be processed with their checkstyle configuration for various reasons, one of which is a valid Java file that won't pass Checkstyle's parser. When Checkstyle tries to parse a Java file and fails, it will throw an Exception and halt parsing any more files for violations. An example of a valid Java file Checkstyle can't parse is JDK 9's module-info.java. This file filter will exclude these problem files from being parsed, allowing the rest of the files to run normal and be validated.
Note: When a file is excluded from the utility, it is excluded from all Checks and no testing for violations will be performed on them.
|fileNamePattern||Regular expression to match the file name against.||Regular Expression||null|
To configure the filter to exclude all 'module-info.java' files:
<module name="BeforeExecutionExclusionFileFilter"> <property name="fileNamePattern" value="module\-info\.java$"/> </module>