Package com.puppycrawl.tools.checkstyle.checks.coding

Class MultipleStringLiteralsCheck

java.lang.Object
com.puppycrawl.tools.checkstyle.AbstractAutomaticBean
com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
com.puppycrawl.tools.checkstyle.api.AbstractCheck
com.puppycrawl.tools.checkstyle.checks.coding.MultipleStringLiteralsCheck
All Implemented Interfaces:
Configurable, Contextualizable
public class MultipleStringLiteralsCheck extends AbstractCheck
Checks for multiple occurrences of the same string literal within a single file.

Rationale: Code duplication makes maintenance more difficult, so it can be better to replace the multiple occurrences with a constant.

  • Property allowedDuplicates - Specify the maximum number of occurrences to allow without generating a warning. Type is int. Default value is 1.
  • Property ignoreOccurrenceContext - Specify token type names where duplicate strings are ignored even if they don't match ignoredStringsRegexp. This allows you to exclude syntactical contexts like annotations or static initializers from the check. Type is java.lang.String[]. Validation type is tokenTypesSet. Default value is ANNOTATION.
  • Property ignoreStringsRegexp - Specify RegExp for ignored strings (with quotation marks). Type is java.util.regex.Pattern. Default value is "^""$".

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

  • multiple.string.literal
Since:
3.5

  • Field Details

    • MSG_KEY

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

    • ALL_NEW_LINES

      private static final Pattern ALL_NEW_LINES
      Compiled pattern for all system newlines.

    • QUOTE

      private static final String QUOTE
      String used to amend TEXT_BLOCK_CONTENT so that it matches STRING_LITERAL.
      See Also:

    • stringMap

      private final Map<String,List<DetailAST>> stringMap
      The found strings and their tokens.

    • ignoreOccurrenceContext

      private final BitSet ignoreOccurrenceContext
      Specify token type names where duplicate strings are ignored even if they don't match ignoredStringsRegexp. This allows you to exclude syntactical contexts like annotations or static initializers from the check.

    • allowedDuplicates

      private int allowedDuplicates
      Specify the maximum number of occurrences to allow without generating a warning.

    • ignoreStringsRegexp

      private Pattern ignoreStringsRegexp
      Specify RegExp for ignored strings (with quotation marks).

  • Constructor Details

  • Method Details

    • setAllowedDuplicates

      public void setAllowedDuplicates(int allowedDuplicates)
      Setter to specify the maximum number of occurrences to allow without generating a warning.
      Parameters:
      allowedDuplicates - The maximum number of duplicates.
      Since:
      3.5

    • setIgnoreStringsRegexp

      public final void setIgnoreStringsRegexp(Pattern ignoreStringsRegexp)
      Setter to specify RegExp for ignored strings (with quotation marks).
      Parameters:
      ignoreStringsRegexp - regular expression pattern for ignored strings
      Since:
      4.0

    • setIgnoreOccurrenceContext

      public final void setIgnoreOccurrenceContext(String... strRep)
      Setter to specify token type names where duplicate strings are ignored even if they don't match ignoredStringsRegexp. This allows you to exclude syntactical contexts like annotations or static initializers from the check.
      Parameters:
      strRep - the string representation of the tokens interested in
      Since:
      4.4

    • 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

    • isInIgnoreOccurrenceContext

      private boolean isInIgnoreOccurrenceContext(DetailAST ast)
      Analyses the path from the AST root to a given AST for occurrences of the token types in ignoreOccurrenceContext.
      Parameters:
      ast - the node from where to start searching towards the root node
      Returns:
      whether the path from the root node to ast contains one of the token type in ignoreOccurrenceContext.

    • beginTree

      public void beginTree(DetailAST rootAST)
      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:
      rootAST - the root of the tree

    • finishTree

      public void finishTree(DetailAST rootAST)
      Description copied from class: AbstractCheck
      Called after finished processing a tree. Ideal place to report on information collected whilst processing a tree.
      Overrides:
      finishTree in class AbstractCheck
      Parameters:
      rootAST - the root of the tree