Class RightCurlyCheck

  • All Implemented Interfaces:
    Configurable, Contextualizable

    public class RightCurlyCheck
    extends AbstractCheck

    Checks the placement of right curly braces (''}) for code blocks. This check supports if-else, try-catch-finally blocks, while-loops, for-loops, method definitions, class definitions, constructor definitions, instance, static initialization blocks, annotation definitions and enum definitions. For right curly brace of expression blocks of arrays, lambdas and class instances please follow issue #5945. For right curly brace of enum constant please follow issue #7519.

    • Property option - Specify the policy on placement of a right curly brace ('}'). Type is com.puppycrawl.tools.checkstyle.checks.blocks.RightCurlyOption. Default value is same.
    • Property tokens - tokens to check Type is java.lang.String[]. Validation type is tokenSet. Default value is: LITERAL_TRY, LITERAL_CATCH, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE.

    To configure the check:

     <module name="RightCurly"/>
     

    Example:

     public class Test {
    
       public void test() {
    
         if (foo) {
           bar();
         }           // violation, right curly must be in the same line as the 'else' keyword
         else {
           bar();
         }
    
         if (foo) {
           bar();
         } else {     // OK
           bar();
         }
    
         if (foo) { bar(); } int i = 0; // violation
                       // ^^^ statement is not allowed on same line after curly right brace
    
         if (foo) { bar(); }            // OK
         int i = 0;
    
         try {
           bar();
         }           // violation, rightCurly must be in the same line as 'catch' keyword
         catch (Exception e) {
           bar();
         }
    
         try {
           bar();
         } catch (Exception e) { // OK
           bar();
         }
    
       }                         // OK
    
       public void testSingleLine() { bar(); } // OK, because singleline is allowed
     }
     

    To configure the check with policy alone for else and METHOD_DEF tokens:

     <module name="RightCurly">
       <property name="option" value="alone"/>
       <property name="tokens" value="LITERAL_ELSE, METHOD_DEF"/>
     </module>
     

    Example:

     public class Test {
    
       public void test() {
    
         if (foo) {
           bar();
         } else { bar(); }   // violation, right curly must be alone on line
    
         if (foo) {
           bar();
         } else {
           bar();
         }                   // OK
    
         try {
           bar();
         } catch (Exception e) { // OK because config is set to token METHOD_DEF and LITERAL_ELSE
           bar();
         }
    
       }                         // OK
    
       public void violate() { bar; } // violation, singleline is not allowed here
    
       public void ok() {
         bar();
       }                              // OK
     }
     

    To configure the check with policy alone_or_singleline for if and METHOD_DEF tokens:

     <module name="RightCurly">
      <property name="option" value="alone_or_singleline"/>
      <property name="tokens" value="LITERAL_IF, METHOD_DEF"/>
     </module>
     

    Example:

     public class Test {
    
       public void test() {
    
         if (foo) {
           bar();
         } else {        // violation, right curly must be alone on line
           bar();
         }
    
         if (foo) {
           bar();
         }               // OK
         else {
           bar();
         }
    
         try {
           bar();
         } catch (Exception e) {        // OK because config did not set token LITERAL_TRY
           bar();
         }
    
       }                                // OK
    
       public void violate() { bar(); } // OK , because singleline
     }
     

    Parent is com.puppycrawl.tools.checkstyle.TreeWalker

    Violation Message Keys:

    • line.alone
    • line.break.before
    • line.same
    Since:
    3.0
    • Method Detail

      • setOption

        public void setOption​(String optionStr)
        Setter to specify the policy on placement of a right curly brace ('}').
        Parameters:
        optionStr - string to decode option from
        Throws:
        IllegalArgumentException - if unable to decode
      • 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
      • validate

        private String validate​(RightCurlyCheck.Details details)
        Does general validation.
        Parameters:
        details - for validation.
        Returns:
        violation message or empty string if there was no violation during validation.
      • shouldHaveLineBreakBefore

        private static boolean shouldHaveLineBreakBefore​(RightCurlyOption bracePolicy,
                                                         RightCurlyCheck.Details details)
        Checks whether a right curly should have a line break before.
        Parameters:
        bracePolicy - option for placing the right curly brace.
        details - details for validation.
        Returns:
        true if a right curly should have a line break before.
      • shouldBeOnSameLine

        private static boolean shouldBeOnSameLine​(RightCurlyOption bracePolicy,
                                                  RightCurlyCheck.Details details)
        Checks that a right curly should be on the same line as the next statement.
        Parameters:
        bracePolicy - option for placing the right curly brace
        details - Details for validation
        Returns:
        true if a right curly should be alone on a line.
      • shouldBeAloneOnLine

        private static boolean shouldBeAloneOnLine​(RightCurlyOption bracePolicy,
                                                   RightCurlyCheck.Details details,
                                                   String targetSrcLine)
        Checks that a right curly should be alone on a line.
        Parameters:
        bracePolicy - option for placing the right curly brace
        details - Details for validation
        targetSrcLine - A string with contents of rcurly's line
        Returns:
        true if a right curly should be alone on a line.
      • shouldBeAloneOnLineWithAloneOption

        private static boolean shouldBeAloneOnLineWithAloneOption​(RightCurlyCheck.Details details,
                                                                  String targetSrcLine)
        Whether right curly should be alone on line when ALONE option is used.
        Parameters:
        details - details for validation.
        targetSrcLine - A string with contents of rcurly's line
        Returns:
        true, if right curly should be alone on line when ALONE option is used.
      • shouldBeAloneOnLineWithNotAloneOption

        private static boolean shouldBeAloneOnLineWithNotAloneOption​(RightCurlyCheck.Details details,
                                                                     String targetSrcLine)
        Whether right curly should be alone on line when ALONE_OR_SINGLELINE or SAME option is used.
        Parameters:
        details - details for validation.
        targetSrcLine - A string with contents of rcurly's line
        Returns:
        true, if right curly should be alone on line when ALONE_OR_SINGLELINE or SAME option is used.
      • isAloneOnLine

        private static boolean isAloneOnLine​(RightCurlyCheck.Details details,
                                             String targetSrcLine)
        Checks whether right curly is alone on a line.
        Parameters:
        details - for validation.
        targetSrcLine - A string with contents of rcurly's line
        Returns:
        true if right curly is alone on a line.
      • skipDoubleBraceInstInit

        private static boolean skipDoubleBraceInstInit​(RightCurlyCheck.Details details)
        This method determines if the double brace initialization should be skipped over by the check. Double brace initializations are treated differently. The corresponding inner rcurly is treated as if it was alone on line even when it may be followed by another rcurly and a semi, raising no violations. Please do note though that the line should not contain anything other than the following right curly and the semi following it or else violations will be raised. Only the kind of double brace initializations shown in the following example code will be skipped over:
             Map<String, String> map = new LinkedHashMap<>() {{
                   put("alpha", "man");
               }}; // no violation
         
        Parameters:
        details - RightCurlyCheck.Details object containing the details relevant to the rcurly
        Returns:
        if the double brace initialization rcurly should be skipped over by the check
      • isBlockAloneOnSingleLine

        private static boolean isBlockAloneOnSingleLine​(RightCurlyCheck.Details details)
        Checks whether block has a single-line format and is alone on a line.
        Parameters:
        details - for validation.
        Returns:
        true if block has single-line format and is alone on a line.
      • isRightcurlyFollowedBySemicolon

        private static boolean isRightcurlyFollowedBySemicolon​(RightCurlyCheck.Details details)
        Checks whether the right curly is followed by a semicolon.
        Parameters:
        details - details for validation.
        Returns:
        true if the right curly is followed by a semicolon.
      • hasLineBreakBefore

        private static boolean hasLineBreakBefore​(DetailAST rightCurly)
        Checks if right curly has line break before.
        Parameters:
        rightCurly - right curly token.
        Returns:
        true, if right curly has line break before.