Class TypeNameCheck

  • All Implemented Interfaces:
    Configurable, Contextualizable

    public class TypeNameCheck
    extends AbstractAccessControlNameCheck

    Checks that type names conform to a specified pattern.

    • Property format - Specifies valid identifiers. Type is java.util.regex.Pattern. Default value is "^[A-Z][a-zA-Z0-9]*$".
    • Property applyToPublic - Controls whether to apply the check to public member. Type is boolean. Default value is true.
    • Property applyToProtected - Controls whether to apply the check to protected member. Type is boolean. Default value is true.
    • Property applyToPackage - Controls whether to apply the check to package-private member. Type is boolean. Default value is true.
    • Property applyToPrivate - Controls whether to apply the check to private member. Type is boolean. Default value is true.
    • Property tokens - tokens to check Type is java.lang.String[]. Validation type is tokenSet. Default value is: CLASS_DEF, INTERFACE_DEF, ENUM_DEF, ANNOTATION_DEF, RECORD_DEF.

    To configure the check:

     <module name="TypeName"/>
     

    Code Example:

     public interface FirstName {} // OK
     protected class SecondName {} // OK
     enum Third_Name {} // violation, name 'Third_Name' must match pattern '^[A-Z][a-zA-Z0-9]*$'
     private class FourthName_ {} // violation, name 'FourthName_'
                                  // must match pattern '^[A-Z][a-zA-Z0-9]*$'
     

    An example of how to configure the check for names that begin with a lower case letter, followed by letters, digits, and underscores. Also, suppress the check from being applied to protected and private type:

     <module name="TypeName">
       <property name="format" value="^[a-z](_?[a-zA-Z0-9]+)*$"/>
       <property name="applyToProtected" value="false"/>
       <property name="applyToPrivate" value="false"/>
     </module>
     

    Code Example:

     public interface firstName {} // OK
     public class SecondName {} // violation, name 'SecondName'
                                // must match pattern '^[a-z](_?[a-zA-Z0-9]+)*$'
     protected class ThirdName {} // OK
     private class FourthName {} // OK
     

    The following configuration element ensures that interface names begin with "I_", followed by letters and digits:

     <module name="TypeName">
       <property name="format"
         value="^I_[a-zA-Z0-9]*$"/>
       <property name="tokens"
         value="INTERFACE_DEF"/>
     </module>
     

    Code Example:

     public interface I_firstName {} // OK
     interface SecondName {} // violation, name 'SecondName'
                             // must match pattern '^I_[a-zA-Z0-9]*$'
     

    Parent is com.puppycrawl.tools.checkstyle.TreeWalker

    Violation Message Keys:

    • name.invalidPattern
    Since:
    3.0