Class NoEnumTrailingCommaCheck

  • All Implemented Interfaces:
    Configurable, Contextualizable

    public class NoEnumTrailingCommaCheck
    extends AbstractCheck

    Checks that enum definition does not contain a trailing comma. Rationale: JLS allows trailing commas in arrays and enumerations, but does not allow them in other locations. To unify the coding style, the use of trailing commas should be prohibited.

     enum Foo1 {
       FOO,
       BAR;
     }
     

    The check demands that there should not be any comma after last constant in enum definition.

     enum Foo1 {
       FOO,
       BAR, //violation
     }
     

    To configure the check:

     <module name="NoEnumTrailingComma"/>
     

    Which results in the following violations:

     enum Foo1 {
       FOO,
       BAR; //OK
     }
     enum Foo2 {
       FOO,
       BAR //OK
     }
     enum Foo3 {
       FOO,
       BAR, //violation
     }
     enum Foo4 {
       FOO,
       BAR, // violation
       ;
     }
     enum Foo5 {
       FOO,
       BAR,; // violation
     }
     enum Foo6 { FOO, BAR,; } // violation
     enum Foo7 { FOO, BAR, } // violation
     enum Foo8 {
       FOO,
       BAR // OK
       ;
     }
     enum Foo9 { FOO, BAR; } // OK
     enum Foo10 { FOO, BAR } // OK
     

    Parent is com.puppycrawl.tools.checkstyle.TreeWalker

    Violation Message Keys:

    • no.enum.trailing.comma
    Since:
    8.29
    • Field Detail

      • MSG_KEY

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

      • NoEnumTrailingCommaCheck

        public NoEnumTrailingCommaCheck()
    • 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
      • visitToken

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