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.

    • Field Detail

      • MSG_KEY

        public static final String MSG_KEY
        A key is pointing to the warning message text in "messages.properties" file.
        See Also:
        Constant Field Values
    • Constructor Detail

      • AvoidStarImportCheck

        public AvoidStarImportCheck()
    • Method Detail

      • getDefaultTokens

        public int[] getDefaultTokens()
        Description copied from class: AbstractCheck
        Returns the default token a check is interested in. Only used if the configuration for a check does not define the tokens.
        Specified by:
        getDefaultTokens in class AbstractCheck
        Returns:
        the default tokens
        See Also:
        TokenTypes
      • 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
      • getRequiredTokens

        public int[] getRequiredTokens()
        Description copied from class: AbstractCheck
        The tokens that this check must be registered for.
        Specified by:
        getRequiredTokens in class AbstractCheck
        Returns:
        the token set this must be registered 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