Class AnnotationOnSameLineCheck

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.annotation.AnnotationOnSameLineCheck
All Implemented Interfaces:
Configurable, Contextualizable
public class AnnotationOnSameLineCheck extends AbstractCheck

Checks that annotations are located on the same line with their targets. Verifying with this check is not good practice, but it is using by some style guides.

To configure the check: 

<module name="AnnotationOnSameLine"/>

Example: 

class Foo {

  @SuppressWarnings("deprecation")  // violation, annotation should be on the same line
  public Foo() {
  }

  @SuppressWarnings("unchecked") public void fun2() {  // OK
  }

}

@SuppressWarnings("unchecked") class Bar extends Foo {  // OK

  @Deprecated public Bar() {  // OK
  }

  @Override  // violation, annotation should be on the same line
  public void fun1() {
  }

  @Before @Override public void fun2() {  // OK
  }

  @SuppressWarnings("deprecation")  // violation, annotation should be on the same line
  @Before public void fun3() {
  }

}

To configure the check to check for annotations applied on interfaces, variables and constructors: 

<module name="AnnotationOnSameLine">
  <property name="tokens"
      value="INTERFACE_DEF, VARIABLE_DEF, CTOR_DEF"/>
</module>

Example: 

@Deprecated interface Foo {  // OK

  void doSomething();

}

class Bar implements Foo {

  @SuppressWarnings("deprecation")  // violation, annotation should be on the same line
  public Bar() {
  }

  @Override  // OK
  public void doSomething() {
  }

  @Nullable  // violation, annotation should be on the same line
  String s;

}

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

  • annotation.same.line
Since:
8.2

  • Field Details

    • MSG_KEY_ANNOTATION_ON_SAME_LINE

      public static final String MSG_KEY_ANNOTATION_ON_SAME_LINE
      A key is pointing to the warning message text in "messages.properties" file.
      See Also:

  • Constructor Details

    • AnnotationOnSameLineCheck

      public AnnotationOnSameLineCheck()

  • Method Details

    • 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

    • getNextNode

      private static DetailAST getNextNode(DetailAST node)
      Finds next node of ast tree.
      Parameters:
      node - current node
      Returns:
      node that is next to given

    • getAnnotationName

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