Package com.qulice.checkstyle

Class ConstructorsCodeFreeCheck

java.lang.Object
com.puppycrawl.tools.checkstyle.AbstractAutomaticBean
com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
com.puppycrawl.tools.checkstyle.api.AbstractCheck
com.qulice.checkstyle.ConstructorsCodeFreeCheck
All Implemented Interfaces:
com.puppycrawl.tools.checkstyle.api.Configurable, com.puppycrawl.tools.checkstyle.api.Contextualizable
public final class ConstructorsCodeFreeCheck extends com.puppycrawl.tools.checkstyle.api.AbstractCheck
Checks that constructors do not contain any method calls.

A constructor must only assign fields from constructor parameters or from newly created objects, and may delegate to another constructor via this(...) or super(...). Calling any method (static or instance) from inside a constructor is forbidden, including as the right-hand side of a field assignment (e.g. this.bar = Foo.createBar()) or as a nested argument to a new expression.

A constructor whose only statement is a delegating this(...) or super(...) call is exempt: such a constructor performs no work of its own, and the method-call arguments to the delegate (e.g. this(System.currentTimeMillis())) are accepted as a sanctioned factory-style entry point.

Method calls nested inside lambda bodies or anonymous class bodies are not considered constructor code, because they are not executed at construction time: only the lambda object or the anonymous class instance is created. Such subtrees are skipped.

Defensive array copy idioms — Arrays.copyOf(...) and <expr>.clone() — are also tolerated, since there is no method-call-free way to defensively copy an array field at construction time (Effective Java item 50).

Since:
0.24

  • Nested Class Summary

    Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.AbstractAutomaticBean

    com.puppycrawl.tools.checkstyle.AbstractAutomaticBean.OutputStreamOptions

  • Constructor Summary

    Constructors
    Constructor
    Description
    ConstructorsCodeFreeCheck()
    Default constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    int[]
    getAcceptableTokens()
     
    int[]
    getDefaultTokens()
     
    int[]
    getRequiredTokens()
     
    void
    visitToken(com.puppycrawl.tools.checkstyle.api.DetailAST ast)
     

    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.AbstractAutomaticBean

    configure, contextualize, getConfiguration, setupChild

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • ConstructorsCodeFreeCheck

      public ConstructorsCodeFreeCheck()
      Default constructor.

  • Method Details

    • 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 ast)
      Overrides:
      visitToken in class com.puppycrawl.tools.checkstyle.api.AbstractCheck