Package com.puppycrawl.tools.checkstyle.checks.coding

Class MissingSwitchDefaultCheck

  • All Implemented Interfaces:
    Configurable, Contextualizable
    public class MissingSwitchDefaultCheck
extends AbstractCheck

    Checks that switch statement has a default clause.

    Rationale: It's usually a good idea to introduce a default case in every switch statement. Even if the developer is sure that all currently possible cases are covered, this should be expressed in the default branch, e.g. by using an assertion. This way the code is protected against later changes, e.g. introduction of new types in an enumeration type. Note that the compiler requires switch expressions to be exhaustive, so this check does not enforce default branches on such expressions.

    To configure the check: 

     <module name="MissingSwitchDefault"/>

    Example of violation:

     switch (i) {    // violation
  case 1:
    break;
  case 2:
    break;
 }

    Example of correct code:

     switch (i) {
  case 1:
    break;
  case 2:
    break;
  default: // OK
    break;
 }

    Parent is com.puppycrawl.tools.checkstyle.TreeWalker

    Violation Message Keys:

    • missing.switch.default
    Since:
    3.1

    • Field Detail

      • MSG_KEY

        public static final java.lang.String MSG_KEY
        A key is pointing to the warning message text in "messages.properties" file.
        See Also:
        Constant Field Values

    • Constructor Detail

      • MissingSwitchDefaultCheck

        public MissingSwitchDefaultCheck()

    • Method Detail

      • 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:
        TokenTypes

      • 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

      • 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:
        TokenTypes