com.github.sevntu.checkstyle.checks.design

Class PublicReferenceToPrivateTypeCheck

java.lang.Object

com.puppycrawl.tools.checkstyle.api.AutomaticBean

com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

com.puppycrawl.tools.checkstyle.api.AbstractCheck

com.github.sevntu.checkstyle.checks.design.PublicReferenceToPrivateTypeCheck

All Implemented Interfaces:

com.puppycrawl.tools.checkstyle.api.Configurable, com.puppycrawl.tools.checkstyle.api.Contextualizable

public class PublicReferenceToPrivateTypeCheck
extends com.puppycrawl.tools.checkstyle.api.AbstractCheck

This Check warns on propagation of inner private types to outer classes:
- Externally accessible method if it returns private inner type.
- Externally accessible field if its type is a private inner type.
These types could be private inner classes, interfaces or enumerations.

Examples:

 class OuterClass {
  public InnerClass innerFromMain = new InnerClass(); //WARNING
  private class InnerClass { ... }
  public InnerClass  getValue() { //WARNING
      return new InnerClass();
  }
  

  private interface InnerInterface { ... }
  public Set<InnerInterface> getValue() { //WARNING
      return new TreeSet<InnerInterface>
  }
  

  private Enum Fruit {Apple, Pear}
  public Fruit getValue() { //WARNING
      return Fruit.Apple;
  }
  

  public someMethod(InnerClass innerClass) { ... }  //WARNING
  

 }
 

Rationale: it is possible to return
private inner type or use it as the parameter of non-private method, but it is impossible
to use it in other classes (besides inner classes)
unless it extends or implements at least one non-private class or interface.
Such situation usually happens after bulk refactoring and usually means dead/useless code

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 and Description
static String	MSG_KEY Check message key for private types.

Constructor Summary

Constructors

Constructor and Description
PublicReferenceToPrivateTypeCheck()

Method Summary

Modifier and Type	Method and Description
void	beginTree(com.puppycrawl.tools.checkstyle.api.DetailAST rootAST)
void	finishTree(com.puppycrawl.tools.checkstyle.api.DetailAST rootAst)
int[]	getAcceptableTokens()
int[]	getDefaultTokens()
int[]	getRequiredTokens()
static boolean	hasModifier(int modifierType, com.puppycrawl.tools.checkstyle.api.DetailAST defAst) Checks if class, interface, enumeration, method or field definition has an access modifier of specified type.
void	visitToken(com.puppycrawl.tools.checkstyle.api.DetailAST defAst)

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck

clearMessages, destroy, getFileContents, getLine, getLines, getMessages, getTabWidth, getTokenNames, 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

Methods inherited from class java.lang.Object

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

Field Detail

MSG_KEY

public static final String MSG_KEY

Check message key for private types.

See Also:

Constant Field Values

Constructor Detail

PublicReferenceToPrivateTypeCheck

public PublicReferenceToPrivateTypeCheck()

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

beginTree

public void beginTree(com.puppycrawl.tools.checkstyle.api.DetailAST rootAST)

Overrides:

beginTree in class com.puppycrawl.tools.checkstyle.api.AbstractCheck

visitToken

public void visitToken(com.puppycrawl.tools.checkstyle.api.DetailAST defAst)

Overrides:

visitToken in class com.puppycrawl.tools.checkstyle.api.AbstractCheck

finishTree

public void finishTree(com.puppycrawl.tools.checkstyle.api.DetailAST rootAst)

Overrides:

finishTree in class com.puppycrawl.tools.checkstyle.api.AbstractCheck

hasModifier

public static boolean hasModifier(int modifierType,
                                  com.puppycrawl.tools.checkstyle.api.DetailAST defAst)

Checks if class, interface, enumeration, method or field definition has an access modifier of specified type.

Parameters:

modifierType - modifier type

defAst - definition ast (METHOD_DEF, FIELD_DEF, etc.)

Returns:

true if class, interface, enumeration, method or field definition has an access modifier of specified type