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

Class SimplifyBooleanReturnCheck

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

    Checks for over-complicated boolean return statements. For example the following code 

     if (valid())
   return false;
 else
   return true;

    could be written as 

     return !valid();

    The idea for this Check has been shamelessly stolen from the equivalent PMD rule.

    To configure the check: 

     <module name="SimplifyBooleanReturn"/>

    Example:

     public class Test {

  private boolean cond;
  private Foo a;
  private Foo b;

  public boolean check1() {
   if (cond) { // violation, can be simplified
     return true;
   }
   else {
     return false;
   }
  }

  // Ok, simplified version of check1()
  public boolean check2() {
   return cond;
  }

  // violations, can be simplified
  public boolean check3() {
   if (cond == true) { // can be simplified to "if (cond)"
     return false;
   }
   else {
     return true; // can be simplified to "return !cond"
   }
  }

  // Ok, can be simplified but doesn't return a Boolean
  public Foo choose1() {
   if (cond) {
     return a;
   }
   else {
     return b;
   }
  }

  // Ok, simplified version of choose1()
  public Foo choose2() {
   return cond ? a: b;
  }

 }

    Parent is com.puppycrawl.tools.checkstyle.TreeWalker

    Violation Message Keys:

    • simplify.boolReturn
    Since:
    3.0

    • 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

      • SimplifyBooleanReturnCheck

        public SimplifyBooleanReturnCheck()

    • Method Detail

      • 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

      • 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

      • 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