com.puppycrawl.tools.checkstyle.checks.coding

Class HiddenFieldCheck

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.HiddenFieldCheck

All Implemented Interfaces:

Configurable, Contextualizable

public class HiddenFieldCheck
extends Check

Checks that a local variable or a parameter does not shadow a field that is defined in the same class.

An example of how to configure the check is:

 <module name="HiddenField"/>
 

An example of how to configure the check so that it checks variables but not parameters is:

 <module name="HiddenField">
    <property name="tokens" value="VARIABLE_DEF"/>
 </module>
 

An example of how to configure the check so that it ignores the parameter of a setter method is:

 <module name="HiddenField">
    <property name="ignoreSetter" value="true"/>
 </module>
 

A method is recognized as a setter if it is in the following form

 ${returnType} set${Name}(${anyType} ${name}) { ... }
 

where ${anyType} is any primitive type, class or interface name; ${name} is name of the variable that is being set and ${Name} its capitalized form that appears in the method name. By default it is expected that setter returns void, i.e. ${returnType} is 'void'. For example

 void setTime(long time) { ... }
 

Any other return types will not let method match a setter pattern. However, by setting setterCanReturnItsClass property to true definition of a setter is expanded, so that setter return type can also be a class in which setter is declared. For example

 class PageBuilder {
   PageBuilder setName(String name) { ... }
 }
 

Such methods are known as chain-setters and a common when Builder-pattern is used. Property setterCanReturnItsClass has effect only if ignoreSetter is set to true.

An example of how to configure the check so that it ignores the parameter of either a setter that returns void or a chain-setter.

 <module name="HiddenField">
    <property name="ignoreSetter" value="true"/>
    <property name="setterCanReturnItsClass" value="true"/>
 </module>
 

An example of how to configure the check so that it ignores constructor parameters is:

 <module name="HiddenField">
    <property name="ignoreConstructorParameter" value="true"/>
 </module>
 

Author:

Dmitri Priimak

Constructor Summary

Constructors

Constructor and Description
HiddenFieldCheck()

Method Summary

Methods

Modifier and Type	Method and Description
void	beginTree(DetailAST rootAST) Called before the starting to process a tree.
int[]	getAcceptableTokens() The configurable token set.
int[]	getDefaultTokens() Returns the default token a check is interested in.
Pattern	getRegexp()
int[]	getRequiredTokens() The tokens that this check must be registered for.
void	leaveToken(DetailAST ast) Called after all the child nodes have been process.
void	setIgnoreAbstractMethods(boolean ignoreAbstractMethods) Set whether to ignore parameters of abstract methods.
void	setIgnoreConstructorParameter(boolean ignoreConstructorParameter) Set whether to ignore constructor parameters.
void	setIgnoreFormat(String format) Set the ignore format to the specified regular expression.
void	setIgnoreSetter(boolean ignoreSetter) Set whether to ignore the parameter of a property setter method.
void	setSetterCanReturnItsClass(boolean aSetterCanReturnItsClass) Controls if setter can return only void (default behavior) or it can also return class in which it is declared.
void	visitToken(DetailAST ast) Called to process a token.

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

destroy, finishTree, getClassLoader, getFileContents, getLine, getLines, getTabWidth, getTokenNames, init, isCommentNodesRequired, 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

HiddenFieldCheck

public HiddenFieldCheck()

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

getAcceptableTokens

public int[] getAcceptableTokens()

Description copied from class: Check

The configurable token set. Used to protect Checks against malicious users who specify an unacceptable token set in the configuration file. The default implementation returns the check's default tokens.

Overrides:

getAcceptableTokens in class Check

Returns:

the token set this check is designed for.

See Also:

TokenTypes

getRequiredTokens

public int[] getRequiredTokens()

Description copied from class: Check

The tokens that this check must be registered for.

Overrides:

getRequiredTokens in class Check

Returns:

the token set this must be registered for.

See Also:

TokenTypes

beginTree

public void beginTree(DetailAST rootAST)

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:

rootAST - the root of the tree

visitToken

public void visitToken(DetailAST ast)

Description copied from class: Check

Called to process a token.

Overrides:

visitToken in class Check

Parameters:

ast - the token to process

leaveToken

public void leaveToken(DetailAST ast)

Description copied from class: Check

Called after all the child nodes have been process.

Overrides:

leaveToken in class Check

Parameters:

ast - the token leaving

setIgnoreFormat

public void setIgnoreFormat(String format)
                     throws org.apache.commons.beanutils.ConversionException

Set the ignore format to the specified regular expression.

Parameters:

format - a String value

Throws:

org.apache.commons.beanutils.ConversionException - unable to parse format

setIgnoreSetter

public void setIgnoreSetter(boolean ignoreSetter)

Set whether to ignore the parameter of a property setter method.

Parameters:

ignoreSetter - decide whether to ignore the parameter of a property setter method.

setSetterCanReturnItsClass

public void setSetterCanReturnItsClass(boolean aSetterCanReturnItsClass)

Controls if setter can return only void (default behavior) or it can also return class in which it is declared.

Parameters:

aSetterCanReturnItsClass - if true then setter can return either void or class in which it is declared. If false then in order to be recognized as setter method (otherwise already recognized as a setter) must return void. Later is the default behavior.

setIgnoreConstructorParameter

public void setIgnoreConstructorParameter(boolean ignoreConstructorParameter)

Set whether to ignore constructor parameters.

Parameters:

ignoreConstructorParameter - decide whether to ignore constructor parameters.

setIgnoreAbstractMethods

public void setIgnoreAbstractMethods(boolean ignoreAbstractMethods)

Set whether to ignore parameters of abstract methods.

Parameters:

ignoreAbstractMethods - decide whether to ignore parameters of abstract methods.

getRegexp

public Pattern getRegexp()

Returns:

the regexp to match against