Class MemberNameCheck

All Implemented Interfaces:
Configurable, Contextualizable

public class MemberNameCheck extends AbstractAccessControlNameCheck

Checks that instance variable 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.

To configure the check:

 <module name="MemberName"/>
 

Code Example:

 class MyClass {
   public int num1; // OK
   protected int num2; // OK
   final int num3 = 3; // OK
   private int num4; // OK

   static int num5; // ignored: not an instance variable
   public static final int CONSTANT = 1; // ignored: not an instance variable

   public int NUM1; // violation, name 'NUM1'
                    // must match pattern '^[a-z][a-zA-Z0-9]*$'
   protected int NUM2; // violation, name 'NUM2'
                       // must match pattern '^[a-z][a-zA-Z0-9]*$'
   final int NUM3; // violation, name 'NUM3'
                   // must match pattern '^[a-z][a-zA-Z0-9]*$'
   private int NUM4; // violation, name 'NUM4'
                     // must match pattern '^[a-z][a-zA-Z0-9]*$'
 }
 

An example of how to configure the check for names that begin with &quot;m&quot;, followed by an upper case letter, and then letters and digits. Also, suppress the check from being applied to protected and package-private member:

 <module name="MemberName">
   <property name="format" value="^m[A-Z][a-zA-Z0-9]*$"/>
   <property name="applyToProtected" value="false"/>
   <property name="applyToPackage" value="false"/>
 </module>
 

Code Example:

 class MyClass {
   public int num1; // violation, name 'num1'
                    // must match pattern '^m[A-Z][a-zA-Z0-9]*$'
   protected int num2; // OK
   int num3; // OK
   private int num4; // violation, name 'num4'
                     // must match pattern '^m[A-Z][a-zA-Z0-9]*$'
 }
 

An example of how to suppress the check which is applied to public and private member:

 <module name="MemberName">
   <property name="applyToPublic" value="false"/>
   <property name="applyToPrivate" value="false"/>
 </module>
 

Code Example:

 class MyClass {
   public int NUM1; // OK
   protected int NUM2; // violation, name 'NUM2'
                       // must match pattern '^[a-z][a-zA-Z0-9]*$'
   int NUM3; // violation, name 'NUM3'
             // must match pattern '^[a-z][a-zA-Z0-9]*$'
   private int NUM4; // OK
 }
 

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

  • name.invalidPattern
Since:
3.0
  • Constructor Details

    • MemberNameCheck

      public MemberNameCheck()
      Creates a new MemberNameCheck instance.
  • Method Details

    • 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:
    • mustCheckName

      protected final boolean mustCheckName(DetailAST ast)
      Description copied from class: AbstractNameCheck
      Decides whether the name of an AST should be checked against the format regexp.
      Overrides:
      mustCheckName in class AbstractAccessControlNameCheck
      Parameters:
      ast - the AST to check.
      Returns:
      true if the IDENT subnode of ast should be checked against the format regexp.