Class SuppressionFilter

  • All Implemented Interfaces:
    Configurable, Contextualizable, ExternalResourceHolder, Filter

    public class SuppressionFilter
    extends AutomaticBean
    implements Filter, ExternalResourceHolder

    Filter SuppressionFilter rejects audit events for Check violations according to a suppressions XML document in a file. If there is no configured suppressions file or the optional is set to true and suppressions file was not found the Filter accepts all audit events.

    A suppressions XML document contains a set of suppress elements, where each suppress element can have the following attributes:

    • files - a Pattern matched against the file name associated with an audit event. It is optional.
    • checks - a Pattern matched against the name of the check associated with an audit event. Optional as long as id or message is specified.
    • message - a Pattern matched against the message of the check associated with an audit event. Optional as long as checks or id is specified.
    • id - a String matched against the check id associated with an audit event. Optional as long as checks or message is specified.
    • lines - a comma-separated list of values, where each value is an int or a range of integers denoted by integer-integer. It is optional.
    • columns - a comma-separated list of values, where each value is an int or a range of integers denoted by integer-integer. It is optional.

    Each audit event is checked against each suppress element. It is suppressed if all specified attributes match against the audit event.

    ATTENTION: filtering by message is dependant on runtime locale. If project is running in different languages it is better to avoid filtering by message.

    You can download template of empty suppression filter here.

    Location of the file defined in file property is checked in the following order:

    1. as a filesystem location
    2. if no file found, and the location starts with either http:// or https://, then it is interpreted as a URL
    3. if no file found, then passed to the ClassLoader.getResource() method.

    SuppressionFilter can suppress Checks that have Treewalker or Checker as parent module.

    • Property file - Specify the location of the suppressions XML document file. Type is java.lang.String. Default value is null.
    • Property optional - Control what to do when the file is not existing. If optional is set to false the file must exist, or else it ends with error. On the other hand if optional is true and file is not found, the filter accept all audit events. Type is boolean. Default value is false.

    For example, the following configuration fragment directs the Checker to use a SuppressionFilter with suppressions file config/suppressions.xml:

     <module name="SuppressionFilter">
       <property name="file" value="config/suppressions.xml"/>
       <property name="optional" value="false"/>
     </module>
     

    The following suppressions XML document directs a SuppressionFilter to reject JavadocStyleCheck violations for lines 82 and 108 to 122 of file AbstractComplexityCheck.java, and MagicNumberCheck violations for line 221 of file JavadocStyleCheck.java, and 'Missing a Javadoc comment' violations for all lines and files:

     <?xml version="1.0"?>
    
     <!DOCTYPE suppressions PUBLIC
       "-//Checkstyle//DTD SuppressionFilter Configuration 1.2//EN"
       "https://checkstyle.org/dtds/suppressions_1_2.dtd">
    
     <suppressions>
       <suppress checks="JavadocStyleCheck"
         files="AbstractComplexityCheck.java"
         lines="82,108-122"/>
       <suppress checks="MagicNumberCheck"
         files="JavadocStyleCheck.java"
         lines="221"/>
       <suppress message="Missing a Javadoc comment"/>
     </suppressions>
     

    Suppress check by module id when config have two instances on the same check:

     <suppress id="stringEqual" files="SomeTestCode.java"/>
     

    Suppress all checks for hidden files and folders:

     <suppress files="[/\\]\..+" checks=".*"/>
     

    Suppress all checks for Maven-generated code:

     <suppress files="[/\\]target[/\\]" checks=".*"/>
     

    Suppress all checks for archives, classes and other binary files:

     <suppress files=".+\.(?:jar|zip|war|class|tar|bin)$" checks=".*"/>
     

    Suppress all checks for image files:

     <suppress files=".+\.(?:png|gif|jpg|jpeg)$" checks=".*"/>
     

    Suppress all checks for non-java files:

     <suppress files=".+\.(?:txt|xml|csv|sh|thrift|html|sql|eot|ttf|woff|css|png)$"
         checks=".*"/>
     

    Suppress all checks in generated sources:

     <suppress checks=".*" files="com[\\/]mycompany[\\/]app[\\/]gen[\\/]"/>
     

    Suppress FileLength check on integration tests in certain folder:

     <suppress checks="FileLength"
       files="com[\\/]mycompany[\\/]app[\\/].*IT.java"/>
     

    Suppress naming violations on variable named 'log' in all files:

     <suppress message="Name 'log' must match pattern"/>
     

    Parent is com.puppycrawl.tools.checkstyle.Checker

    Since:
    3.2
    • Field Detail

      • file

        private String file
        Specify the location of the suppressions XML document file.
      • optional

        private boolean optional
        Control what to do when the file is not existing. If optional is set to false the file must exist, or else it ends with error. On the other hand if optional is true and file is not found, the filter accept all audit events.
    • Method Detail

      • setFile

        public void setFile​(String fileName)
        Setter to specify the location of the suppressions XML document file.
        Parameters:
        fileName - name of the suppressions file.
      • setOptional

        public void setOptional​(boolean optional)
        Setter to control what to do when the file is not existing. If optional is set to false the file must exist, or else it ends with error. On the other hand if optional is true and file is not found, the filter accept all audit events.
        Parameters:
        optional - tells if config file existence is optional.
      • accept

        public boolean accept​(AuditEvent event)
        Description copied from interface: Filter
        Determines whether or not a filtered AuditEvent is accepted.
        Specified by:
        accept in interface Filter
        Parameters:
        event - the AuditEvent to filter.
        Returns:
        true if the event is accepted.