Class ParameterNumberCheck

  • All Implemented Interfaces:
    Configurable, Contextualizable

    public class ParameterNumberCheck
    extends AbstractCheck

    Checks the number of parameters of a method or constructor.

    • Property max - Specify the maximum number of parameters allowed. Type is int. Default value is 7.
    • Property ignoreOverriddenMethods - Ignore number of parameters for methods with @Override annotation. 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:

     <module name="ParameterNumber"/>
     

    To configure the check to allow 10 parameters for a method:

     <module name="ParameterNumber">
       <property name="max" value="10"/>
       <property name="tokens" value="METHOD_DEF"/>
     </module>
     

    To configure the check to ignore number of parameters for methods with @Override or @java.lang.Override annotation.

    Rationale: developer may need to override method with many parameters from 3-rd party library. In this case developer has no control over number of parameters.

     <module name="ParameterNumber">
       <property name="ignoreOverriddenMethods" value="true"/>
     </module>
     

    Java code example:

     @Override
     public void needsLotsOfParameters(int a,
         int b, int c, int d, int e, int f, int g, int h) {
         ...
     }
     

    Parent is com.puppycrawl.tools.checkstyle.TreeWalker

    Violation Message Keys:

    • maxParam
    Since:
    3.0
    • Method Detail

      • setMax

        public void setMax​(int max)
        Setter to specify the maximum number of parameters allowed.
        Parameters:
        max - the max allowed parameters
      • setIgnoreOverriddenMethods

        public void setIgnoreOverriddenMethods​(boolean ignoreOverriddenMethods)
        Setter to ignore number of parameters for methods with @Override annotation.
        Parameters:
        ignoreOverriddenMethods - set ignore overridden methods
      • 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
      • shouldIgnoreNumberOfParameters

        private boolean shouldIgnoreNumberOfParameters​(DetailAST ast)
        Determine whether to ignore number of parameters for the method.
        Parameters:
        ast - the token to process
        Returns:
        true if this is overridden method and number of parameters should be ignored false otherwise