Class AvoidStarImportCheck

  • All Implemented Interfaces:
    Configurable, Contextualizable

    public class AvoidStarImportCheck
    extends AbstractCheck

    Check that finds import statements that use the * notation.

    Rationale: Importing all classes from a package or static members from a class leads to tight coupling between packages or classes and might lead to problems when a new version of a library introduces name clashes.

    An example of how to configure the check is:

     <module name="AvoidStarImport">
       <property name="excludes" value="java.io,java.net,java.lang.Math"/>
       <property name="allowClassImports" value="false"/>
       <property name="allowStaticMemberImports" value="false"/>
     </module>
     
    The optional "excludes" property allows for certain packages like java.io or java.net to be exempted from the rule. It also is used to allow certain classes like java.lang.Math or java.io.File to be excluded in order to support static member imports.

    The optional "allowClassImports" when set to true, will allow starred class imports but will not affect static member imports.

    The optional "allowStaticMemberImports" when set to true will allow starred static member imports but will not affect class imports.

    Author:
    Oliver Burn, Bill Schneider, Travis Schneeberger
    • Method Detail

      • getAcceptableTokens

        public int[] getAcceptableTokens()
        Description copied from class: AbstractCheck
        The configurable token set. Used to protect Checks against malicious users who specify an unacceptable token set in the configuration file. The default implementation returns the check's default tokens.
        Specified by:
        getAcceptableTokens in class AbstractCheck
        Returns:
        the token set this check is designed for.
        See Also:
        TokenTypes
      • setExcludes

        public void setExcludes​(String... excludesParam)
        Sets the list of packages or classes to be exempt from the check. The excludes can contain a .* or not.
        Parameters:
        excludesParam - a list of package names/fully-qualifies class names where star imports are ok.
      • setAllowClassImports

        public void setAllowClassImports​(boolean allow)
        Sets whether or not to allow all non-static class imports.
        Parameters:
        allow - true to allow false to disallow
      • setAllowStaticMemberImports

        public void setAllowStaticMemberImports​(boolean allow)
        Sets whether or not to allow all static member imports.
        Parameters:
        allow - true to allow false to disallow