com.puppycrawl.tools.checkstyle.checks.coding
Class EqualsHashCodeCheck

java.lang.Object
  extended bycom.puppycrawl.tools.checkstyle.api.AutomaticBean
      extended bycom.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
          extended bycom.puppycrawl.tools.checkstyle.api.Check
              extended bycom.puppycrawl.tools.checkstyle.checks.coding.EqualsHashCodeCheck
All Implemented Interfaces:
Configurable, Contextualizable

public class EqualsHashCodeCheck
extends Check

Checks that classes that override equals() also override hashCode().

Rationale: The contract of equals() and hashCode() requires that equal objects have the same hashCode. Hence, whenever you override equals() you must override hashCode() to ensure that your class can be used in collections that are hash based.

An example of how to configure the check is:

 <module name="EqualsHashCode"/>
 

Author:
lkuehne

Constructor Summary
EqualsHashCodeCheck()
           
 
Method Summary
 void beginTree(DetailAST aRootAST)
          Called before the starting to process a tree.
 void finishTree(DetailAST aRootAST)
          Called after finished processing a tree.
 int[] getDefaultTokens()
          Returns the default token a check is interested in.
 void visitToken(DetailAST aAST)
          Called to process a token.
 
Methods inherited from class com.puppycrawl.tools.checkstyle.api.Check
destroy, getAcceptableTokens, getClassLoader, getFileContents, getLines, getRequiredTokens, getTabWidth, getTokenNames, init, leaveToken, log, log, setClassLoader, setFileContents, setMessages, setTabWidth, setTokens
 
Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
getMessageBundle, getSeverity, getSeverityLevel, log, log, log, log, log, log, log, log, log, setSeverity
 
Methods inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean
configure, contextualize, finishLocalSetup, getConfiguration, setupChild
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

EqualsHashCodeCheck

public EqualsHashCodeCheck()
Method Detail

getDefaultTokens

public int[] getDefaultTokens()
Description copied from class: Check
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 Check
Returns:
the default tokens
See Also:
Check

beginTree

public void beginTree(DetailAST aRootAST)
Description copied from class: Check
Called before the starting to process a tree. Ideal place to initialise information that is to be collected whilst processing a tree.

Overrides:
beginTree in class Check
Parameters:
aRootAST - the root of the tree
See Also:
Check

visitToken

public void visitToken(DetailAST aAST)
Description copied from class: Check
Called to process a token.

Overrides:
visitToken in class Check
Parameters:
aAST - the token to process
See Also:
Check

finishTree

public void finishTree(DetailAST aRootAST)
Description copied from class: Check
Called after finished processing a tree. Ideal place to report on information collected whilst processing a tree.

Overrides:
finishTree in class Check
Parameters:
aRootAST - the root of the tree
See Also:
Check

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