Class DiamondOperatorForVariableDefinitionCheck

  • All Implemented Interfaces:
    com.puppycrawl.tools.checkstyle.api.Configurable, com.puppycrawl.tools.checkstyle.api.Contextualizable

    public class DiamondOperatorForVariableDefinitionCheck
    extends com.puppycrawl.tools.checkstyle.api.AbstractCheck
    This Check highlights variable definition statements where diamond operator could be used.
    Rationale: using diamond operator (introduced in Java 1.7) leads to shorter code
    and better code readability. It is suggested by Oracle that the diamond primarily using
    for variable declarations.

    E.g. of statements:

    Without diamond operator:
    Map<String, Map<String, Integer>> someMap = new HashMap<String, Map<String, Integer>>();
    With diamond operator:
    Map<String, Map<String, Integer>> someMap = new HashMap<>();

    Since:
    1.12.0
    Author:
    Aleksey Nesterenko
    • Nested Class Summary

      • Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

        com.puppycrawl.tools.checkstyle.api.AutomaticBean.OutputStreamOptions
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static String MSG_KEY
      A key is pointing to the warning message text in "messages.properties" file.
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int[] getAcceptableTokens()  
      int[] getDefaultTokens()  
      int[] getRequiredTokens()  
      void visitToken​(com.puppycrawl.tools.checkstyle.api.DetailAST variableDefNode)  
      • Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck

        beginTree, clearViolations, destroy, finishTree, getFileContents, getFilePath, getLine, getLineCodePoints, getLines, getTabWidth, getTokenNames, getViolations, init, isCommentNodesRequired, leaveToken, log, log, log, setFileContents, setTabWidth, setTokens
      • Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

        finishLocalSetup, getCustomMessages, getId, getMessageBundle, getSeverity, getSeverityLevel, setId, setSeverity
      • Methods inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

        configure, contextualize, getConfiguration, setupChild
    • Field Detail

      • MSG_KEY

        public static final String MSG_KEY
        A key is pointing to the warning message text in "messages.properties" file.
        See Also:
        Constant Field Values
    • Constructor Detail

      • DiamondOperatorForVariableDefinitionCheck

        public DiamondOperatorForVariableDefinitionCheck()
    • Method Detail

      • getDefaultTokens

        public int[] getDefaultTokens()
        Specified by:
        getDefaultTokens in class com.puppycrawl.tools.checkstyle.api.AbstractCheck
      • getAcceptableTokens

        public int[] getAcceptableTokens()
        Specified by:
        getAcceptableTokens in class com.puppycrawl.tools.checkstyle.api.AbstractCheck
      • getRequiredTokens

        public int[] getRequiredTokens()
        Specified by:
        getRequiredTokens in class com.puppycrawl.tools.checkstyle.api.AbstractCheck
      • visitToken

        public void visitToken​(com.puppycrawl.tools.checkstyle.api.DetailAST variableDefNode)
        Overrides:
        visitToken in class com.puppycrawl.tools.checkstyle.api.AbstractCheck