Class UpperEllCheck

  • All Implemented Interfaces:
    Configurable, Contextualizable

    public class UpperEllCheck
    extends AbstractCheck

    Checks that long constants are defined with an upper ell. That is 'L' and not 'l'. This is in accordance with the Java Language Specification, Section 3.10.1.

    Rationale: The lower-case ell 'l' looks a lot like 1.

    To configure the check:

     <module name="UpperEll"/>
     
     class Test {
       long var1 = 508987; // OK
       long var2 = 508987l; // violation
       long var3 = 508987L; // OK
     }
     

    Parent is com.puppycrawl.tools.checkstyle.TreeWalker

    Violation Message Keys:

    • upperEll
    Since:
    3.0
    • 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

      • UpperEllCheck

        public UpperEllCheck()
    • 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