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 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.


name description type default value
fileNamePattern Regular expression to match the file name against. Regular Expression null


To configure the filter to exclude all '' files:

<module name="BeforeExecutionExclusionFileFilter">
  <property name="fileNamePattern" value="module\-info\.java$"/>

Example of Usage


Parent Module