Class ParameterNumberCheck

java.lang.Object
com.puppycrawl.tools.checkstyle.api.AutomaticBean
com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
com.puppycrawl.tools.checkstyle.api.AbstractCheck
com.puppycrawl.tools.checkstyle.checks.sizes.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

  • 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:

    • OVERRIDE

      private static final String OVERRIDE
      Override annotation name.
      See Also:

    • CANONICAL_OVERRIDE

      private static final String CANONICAL_OVERRIDE
      Canonical Override annotation name.
      See Also:

    • DEFAULT_MAX_PARAMETERS

      private static final int DEFAULT_MAX_PARAMETERS
      Default maximum number of allowed parameters.
      See Also:

    • max

      private int max
      Specify the maximum number of parameters allowed.

    • ignoreOverriddenMethods

      private boolean ignoreOverriddenMethods
      Ignore number of parameters for methods with @Override annotation.

  • Constructor Details

    • ParameterNumberCheck

      public ParameterNumberCheck()

  • Method Details

    • 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

    • 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

    • 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