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

    java.lang.Object
      com.puppycrawl.tools.checkstyle.api.AutomaticBean
          com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
              com.puppycrawl.tools.checkstyle.api.Check
                  com.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
`getCustomMessages, getId, getMessageBundle, getSeverity, getSeverityLevel, log, setId, 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:
    `TokenTypes`

### 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

### 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

### 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

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