Package com.puppycrawl.tools.checkstyle.checks.javadoc

Class JavadocContentLocationCheck

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

    Checks that the Javadoc content begins from the same position for all Javadoc comments in the project. Any leading asterisks and spaces are not counted as the beginning of the content and are therefore ignored.

    It is possible to enforce two different styles:

    • first_line - Javadoc content starts from the first line: 
       /** Summary text.
   * More details.
   */
 public void method();
    • second_line - Javadoc content starts from the second line: 
       /**
   * Summary text.
   * More details.
   */
 public void method();

    This check does not validate the Javadoc summary itself nor its presence. The check will not report any violations for missing or malformed javadoc summary. To validate the Javadoc summary use SummaryJavadoc check.

    The Documentation Comment Specification permits leading asterisks on the first line. For these Javadoc comments: 

     /***
   * Some text.
   */
 /************
   * Some text.
   */
 /**           **
   * Some text.
   */

    The documentation generated will be just "Some text." without any asterisks. Since these asterisks will not appear in the generated documentation, they should not be considered as the beginning of the Javadoc content. In such cases, the check assumes that the Javadoc content begins on the second line.

    • Property location - Specify the policy on placement of the Javadoc content. Type is com.puppycrawl.tools.checkstyle.checks.javadoc.JavadocContentLocationOption. Default value is second_line.

    To configure the default check to validate that the Javadoc content starts from the second line: 

     <module name="JavadocContentLocationCheck"/>

    This setting produces a violation for each multi-line comment starting on the same line as the initial asterisks: 

     /** This comment causes a violation because it starts from the first line
   * and spans several lines.
   */
 /**
   * This comment is OK because it starts from the second line.
   */
 /** This comment is OK because it is on the single-line. */

    To ensure that Javadoc content starts from the first line: 

     <module name="JavadocContentLocationCheck">
   <property name="location" value="first_line"/>
 </module>

    This setting produces a violation for each comment not starting on the same line as the initial asterisks: 

     /** This comment is OK because it starts on the first line.
    * There may be additional text.
    */
 /**
   * This comment causes a violation because it starts on the second line.
   */
 /** This single-line comment also is OK. */

    Parent is com.puppycrawl.tools.checkstyle.TreeWalker

    Violation Message Keys:

    • javadoc.content.first.line
    • javadoc.content.second.line
    Since:
    8.27

    • 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

      • setLocation

        public void setLocation​(java.lang.String value)
        Setter to specify the policy on placement of the Javadoc content.
        Parameters:
        value - string to decode location from
        Throws:
        java.lang.IllegalArgumentException - if unable to decode

      • isMultilineComment

        private static boolean isMultilineComment​(DetailAST node)
        Checks if a DetailAST of type TokenTypes.BLOCK_COMMENT_BEGIN span more than one line. The node always has at least one child of the type TokenTypes.BLOCK_COMMENT_END.
        Parameters:
        node - node to check
        Returns:
        true for multi-line comment nodes

      • findIndexOfFirstNonBlankLine

        private static int findIndexOfFirstNonBlankLine​(java.lang.String commentContent)
        Returns the index of the first non-blank line. All lines consists only of asterisks and whitespaces are treated as blank.
        Parameters:
        commentContent - Javadoc content to process
        Returns:
        the index of the first non-blank line or -1 if all lines are blank