Package com.puppycrawl.tools.checkstyle.checks.annotation

Class AnnotationLocationCheck

java.lang.Object
com.puppycrawl.tools.checkstyle.AbstractAutomaticBean
com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
com.puppycrawl.tools.checkstyle.api.AbstractCheck
com.puppycrawl.tools.checkstyle.checks.annotation.AnnotationLocationCheck
All Implemented Interfaces:
Configurable, Contextualizable
public class AnnotationLocationCheck extends AbstractCheck
Checks location of annotation on language elements. By default, Check enforce to locate annotations immediately after documentation block and before target element, annotation should be located on separate line from target element. This check also verifies that the annotations are on the same indenting level as the annotated element if they are not on the same line.

Attention: Elements that cannot have JavaDoc comments like local variables are not in the scope of this check even though a token type like VARIABLE_DEF would match them.

Attention: Annotations among modifiers are ignored (looks like false-negative) as there might be a problem with annotations for return types: 

 public @Nullable Long getStartTimeOrNull() { ... }

Such annotations are better to keep close to type. Due to limitations, Checkstyle can not examine the target of an annotation.

Example: 

 @Override
 @Nullable
 public String getNameIfPresent() { ... }
  • Property allowSamelineMultipleAnnotations - Allow annotation(s) to be located on the same line as target element. Type is boolean. Default value is false.
  • Property allowSamelineParameterizedAnnotation - Allow one and only parameterized annotation to be located on the same line as target element. Type is boolean. Default value is false.
  • Property allowSamelineSingleParameterlessAnnotation - Allow single parameterless annotation to be located on the same line as target element. Type is boolean. Default value is true.
  • Property tokens - tokens to check Type is java.lang.String[]. Validation type is tokenSet. Default value is: CLASS_DEF, INTERFACE_DEF, PACKAGE_DEF, ENUM_CONSTANT_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF, VARIABLE_DEF, RECORD_DEF, COMPACT_CTOR_DEF.

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

  • annotation.location
  • annotation.location.alone
Since:
6.0

  • Field Details

  • Constructor Details

  • Method Details

    • setAllowSamelineSingleParameterlessAnnotation

      public final void setAllowSamelineSingleParameterlessAnnotation(boolean allow)
      Setter to allow single parameterless annotation to be located on the same line as target element.
      Parameters:
      allow - User's value of allowSamelineSingleParameterlessAnnotation.
      Since:
      6.1

    • setAllowSamelineParameterizedAnnotation

      public final void setAllowSamelineParameterizedAnnotation(boolean allow)
      Setter to allow one and only parameterized annotation to be located on the same line as target element.
      Parameters:
      allow - User's value of allowSamelineParameterizedAnnotation.
      Since:
      6.4

    • setAllowSamelineMultipleAnnotations

      public final void setAllowSamelineMultipleAnnotations(boolean allow)
      Setter to allow annotation(s) to be located on the same line as target element.
      Parameters:
      allow - User's value of allowSamelineMultipleAnnotations.
      Since:
      6.0

    • 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

    • getExpectedAnnotationIndentation

      private static int getExpectedAnnotationIndentation(DetailAST node)
      Returns an expected annotation indentation. The expected indentation should be the same as the indentation of the target node.
      Parameters:
      node - modifiers or annotations node.
      Returns:
      the annotation indentation.

    • checkAnnotations

      private void checkAnnotations(DetailAST modifierNode, int correctIndentation)
      Checks annotations positions in code: 1) Checks whether the annotations locations are correct. 2) Checks whether the annotations have the valid indentation level.
      Parameters:
      modifierNode - modifiers node.
      correctIndentation - correct indentation of the annotation.

    • isParameterized

      private static boolean isParameterized(DetailAST annotation)
      Checks whether an annotation has parameters.
      Parameters:
      annotation - annotation node.
      Returns:
      true if the annotation has parameters.

    • getAnnotationName

      private static String getAnnotationName(DetailAST annotation)
      Returns the name of the given annotation.
      Parameters:
      annotation - annotation node.
      Returns:
      annotation name.

    • isCorrectLocation

      private boolean isCorrectLocation(DetailAST annotation, boolean hasParams)
      Checks whether an annotation has a correct location. Annotation location is considered correct if allowSamelineMultipleAnnotations is set to true. The method also: 1) checks parameterized annotation location considering the value of allowSamelineParameterizedAnnotation; 2) checks parameterless annotation location considering the value of allowSamelineSingleParameterlessAnnotation; 3) checks annotation location;
      Parameters:
      annotation - annotation node.
      hasParams - whether an annotation has parameters.
      Returns:
      true if the annotation has a correct location.

    • hasNodeBefore

      private static boolean hasNodeBefore(DetailAST annotation)
      Checks whether an annotation node has any node before on the same line.
      Parameters:
      annotation - annotation node.
      Returns:
      true if an annotation node has any node before on the same line.

    • hasNodeBeside

      private static boolean hasNodeBeside(DetailAST annotation)
      Checks whether an annotation node has any node before or after on the same line.
      Parameters:
      annotation - annotation node.
      Returns:
      true if an annotation node has any node before or after on the same line.

    • hasNodeAfter

      private static boolean hasNodeAfter(DetailAST annotation)
      Checks whether an annotation node has any node after on the same line.
      Parameters:
      annotation - annotation node.
      Returns:
      true if an annotation node has any node after on the same line.