Package com.puppycrawl.tools.checkstyle.checks.imports

Class RedundantImportCheck

java.lang.Object
com.puppycrawl.tools.checkstyle.api.AutomaticBean
com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
com.puppycrawl.tools.checkstyle.api.AbstractCheck
com.puppycrawl.tools.checkstyle.checks.imports.RedundantImportCheck
All Implemented Interfaces:
Configurable, Contextualizable
public class RedundantImportCheck extends AbstractCheck

Checks for redundant import statements. An import statement is considered redundant if:

  • It is a duplicate of another import. This is, when a class is imported more than once.
  • The class non-statically imported is from the java.lang package, e.g. importing java.lang.String.
  • The class non-statically imported is from the same package as the current package.

To configure the check: 

 <module name="RedundantImport"/>

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

  • import.duplicate
  • import.lang
  • import.same
Since:
3.0

  • Field Details

    • MSG_LANG

      public static final String MSG_LANG
      A key is pointing to the warning message text in "messages.properties" file.
      See Also:

    • MSG_SAME

      public static final String MSG_SAME
      A key is pointing to the warning message text in "messages.properties" file.
      See Also:

    • MSG_DUPLICATE

      public static final String MSG_DUPLICATE
      A key is pointing to the warning message text in "messages.properties" file.
      See Also:

  • Constructor Details

    • RedundantImportCheck

      public RedundantImportCheck()

  • Method Details

    • beginTree

      public void beginTree(DetailAST aRootAST)
      Description copied from class: AbstractCheck
      Called before the starting to process a tree. Ideal place to initialize information that is to be collected whilst processing a tree.
      Overrides:
      beginTree in class AbstractCheck
      Parameters:
      aRootAST - the root of the tree

    • 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:

    • 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:

    • 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:

    • visitToken

      public void visitToken(DetailAST ast)
      Description copied from class: AbstractCheck
      Called to process a token.
      Overrides:
      visitToken in class AbstractCheck
      Parameters:
      ast - the token to process