Class FinalParametersCheck

All Implemented Interfaces:
Configurable, Contextualizable

public class FinalParametersCheck extends AbstractCheck

Checks that parameters for methods, constructors, catch and for-each blocks are final. Interface, abstract, and native methods are not checked: the final keyword does not make sense for interface, abstract, and native method parameters as there is no code that could modify the parameter.

Rationale: Changing the value of parameters during the execution of the method's algorithm can be confusing and should be avoided. A great way to let the Java compiler prevent this coding style is to declare parameters final.

  • Property ignorePrimitiveTypes - Ignore primitive types as parameters. Type is boolean. Default value is false.
  • Property tokens - tokens to check Type is java.lang.String[]. Validation type is tokenSet. Default value is: METHOD_DEF, CTOR_DEF.

To configure the check to enforce final parameters for methods and constructors:

 <module name="FinalParameters"/>
 

To configure the check to enforce final parameters only for constructors:

 <module name="FinalParameters">
   <property name="tokens" value="CTOR_DEF"/>
 </module>
 

To configure the check to allow ignoring primitive datatypes as parameters:

 <module name="FinalParameters">
   <property name="ignorePrimitiveTypes" value="true"/>
 </module>
 

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

  • final.parameter
Since:
3.0
  • Field Details

    • MSG_KEY

      public static final String MSG_KEY
      A key is pointing to the warning message text in "messages.properties" file.
      See Also:
  • Constructor Details

    • FinalParametersCheck

      public FinalParametersCheck()
  • Method Details

    • setIgnorePrimitiveTypes

      public void setIgnorePrimitiveTypes(boolean ignorePrimitiveTypes)
      Setter to ignore primitive types as parameters.
      Parameters:
      ignorePrimitiveTypes - true or false.
    • 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:
    • 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