Class AvoidEscapedUnicodeCharactersCheck

All Implemented Interfaces:
Configurable, Contextualizable

Restricts using Unicode escapes (such as \u221e). It is possible to allow using escapes for non-printable, control characters. Also, this check can be configured to allow using escapes if trail comment is present. By the option it is possible to allow using escapes if literal contains only them.
  • Property allowByTailComment - Allow use escapes if trail comment is present. Type is boolean. Default value is false.
  • Property allowEscapesForControlCharacters - Allow use escapes for non-printable, control characters. Type is boolean. Default value is false.
  • Property allowIfAllCharactersEscaped - Allow if all characters in literal are escaped. Type is boolean. Default value is false.
  • Property allowNonPrintableEscapes - Allow use escapes for non-printable, whitespace characters. Type is boolean. Default value is false.

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

  • forbid.escaped.unicode.char
Since:
5.8
  • Field Details

  • Constructor Details

  • Method Details

    • setAllowEscapesForControlCharacters

      public final void setAllowEscapesForControlCharacters(boolean allow)
      Setter to allow use escapes for non-printable, control characters.
      Parameters:
      allow - user's value.
      Since:
      5.8
    • setAllowByTailComment

      public final void setAllowByTailComment(boolean allow)
      Setter to allow use escapes if trail comment is present.
      Parameters:
      allow - user's value.
      Since:
      5.8
    • setAllowIfAllCharactersEscaped

      public final void setAllowIfAllCharactersEscaped(boolean allow)
      Setter to allow if all characters in literal are escaped.
      Parameters:
      allow - user's value.
      Since:
      5.8
    • setAllowNonPrintableEscapes

      public final void setAllowNonPrintableEscapes(boolean allow)
      Setter to allow use escapes for non-printable, whitespace characters.
      Parameters:
      allow - user's value.
      Since:
      5.8
    • 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:
    • 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
    • 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
    • hasUnicodeChar

      private static boolean hasUnicodeChar(String literal)
      Checks if literal has Unicode chars.
      Parameters:
      literal - String literal.
      Returns:
      true if literal has Unicode chars.
    • isOnlyUnicodeValidChars

      private static boolean isOnlyUnicodeValidChars(String literal, Pattern pattern)
      Check if String literal contains Unicode control chars.
      Parameters:
      literal - String literal.
      pattern - RegExp for valid characters.
      Returns:
      true, if String literal contains Unicode control chars.
    • hasTrailComment

      private boolean hasTrailComment(DetailAST ast)
      Check if trail comment is present after ast token.
      Parameters:
      ast - current token.
      Returns:
      true if trail comment is present after ast token.
    • isTrailingBlockComment

      private static boolean isTrailingBlockComment(TextBlock comment, int... codePoints)
      Whether the C style comment is trailing.
      Parameters:
      comment - the comment to check.
      codePoints - the first line of the comment, in unicode code points
      Returns:
      true if the comment is trailing.
    • countMatches

      private static int countMatches(Pattern pattern, String target)
      Count regexp matches into String literal.
      Parameters:
      pattern - pattern.
      target - String literal.
      Returns:
      count of regexp matches.
    • isAllCharactersEscaped

      private boolean isAllCharactersEscaped(String literal)
      Checks if all characters in String literal is escaped.
      Parameters:
      literal - current literal.
      Returns:
      true if all characters in String literal is escaped.