Class HiddenFieldCheck
- java.lang.Object
-
- com.puppycrawl.tools.checkstyle.api.AutomaticBean
-
- com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
-
- com.puppycrawl.tools.checkstyle.api.AbstractCheck
-
- com.puppycrawl.tools.checkstyle.checks.coding.HiddenFieldCheck
-
- All Implemented Interfaces:
Configurable
,Contextualizable
public class HiddenFieldCheck extends AbstractCheck
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. ${returnType} is 'void'. For examplevoid setTime(long time) { ... }
Any other return types will not let method match a setter pattern. However, by setting setterCanReturnItsClass property to true definition of a setter is expanded, so that setter return type can also be a class in which setter is declared. For exampleclass PageBuilder { PageBuilder setName(String name) { ... } }
Such methods are known as chain-setters and a common when Builder-pattern is used. Property setterCanReturnItsClass has effect only if ignoreSetter is set to true.An example of how to configure the check so that it ignores the parameter of either a setter that returns void or a chain-setter.
<module name="HiddenField"> <property name="ignoreSetter" value="true"/> <property name="setterCanReturnItsClass" value="true"/> </module>
An example of how to configure the check so that it ignores constructor parameters is:
<module name="HiddenField"> <property name="ignoreConstructorParameter" value="true"/> </module>
An example of how to configure the check so that it ignores variables and parameters named 'test':
<module name="HiddenField"> <property name="ignoreFormat" value="^test$"/> </module>
class SomeClass { private List<String> test; private void addTest(List<String> test) // no violation { this.test.addAll(test); } private void foo() { final List<String> test = new ArrayList<>(); // no violation ... } }
-
-
Nested Class Summary
Nested Classes Modifier and Type Class Description private static class
HiddenFieldCheck.FieldFrame
Holds the names of static and instance fields of a type.
-
Field Summary
Fields Modifier and Type Field Description private HiddenFieldCheck.FieldFrame
frame
Stack of sets of field names, one for each class of a set of nested classes.private boolean
ignoreAbstractMethods
Controls whether to check the parameter of abstract methods.private boolean
ignoreConstructorParameter
Controls whether to check the parameter of a constructor.private java.util.regex.Pattern
ignoreFormat
Pattern for names of variables and parameters to ignore.private boolean
ignoreSetter
Controls whether to check the parameter of a property setter method.static java.lang.String
MSG_KEY
A key is pointing to the warning message text in "messages.properties" file.private boolean
setterCanReturnItsClass
If ignoreSetter is set to true then this variable controls what the setter method can return By default setter must return void.
-
Constructor Summary
Constructors Constructor Description HiddenFieldCheck()
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description void
beginTree(DetailAST rootAST)
Called before the starting to process a tree.private static java.lang.String
capitalize(java.lang.String name)
Capitalizes a given property name the way we expect to see it in a setter name.int[]
getAcceptableTokens()
The configurable token set.int[]
getDefaultTokens()
Returns the default token a check is interested in.int[]
getRequiredTokens()
The tokens that this check must be registered for.private boolean
isIgnoredConstructorParam(DetailAST ast)
Decides whether to ignore an AST node that is the parameter of a constructor.private boolean
isIgnoredParam(DetailAST ast, java.lang.String name)
Checks whether method or constructor parameter is ignored.private boolean
isIgnoredParamOfAbstractMethod(DetailAST ast)
Decides whether to ignore an AST node that is the parameter of an abstract method.private boolean
isIgnoredSetterParam(DetailAST ast, java.lang.String name)
Decides whether to ignore an AST node that is the parameter of a setter method, where the property setter method for field 'xyz' has name 'setXyz', one parameter named 'xyz', and return type void (default behavior) or return type is name of the class in which such method is declared (allowed only ifsetSetterCanReturnItsClass(boolean)
is called with value true).private static boolean
isInStatic(DetailAST ast)
Determines whether an AST node is in a static method or static initializer.private boolean
isMatchingRegexp(java.lang.String name)
Check name by regExp.private boolean
isSetterMethod(DetailAST aMethodAST, java.lang.String aName)
Determine if a specific method identified by methodAST and a single variable name aName is a setter.private boolean
isStaticFieldHiddenFromAnonymousClass(DetailAST nameAST, java.lang.String name)
Checks whether a static field is hidden from closure.private boolean
isStaticOrInstanceField(DetailAST ast, java.lang.String name)
Check for static or instance field.void
leaveToken(DetailAST ast)
Called after all the child nodes have been process.private void
processLambda(DetailAST ast)
Process a lambda token.private void
processVariable(DetailAST ast)
Process a variable token.void
setIgnoreAbstractMethods(boolean ignoreAbstractMethods)
Set whether to ignore parameters of abstract methods.void
setIgnoreConstructorParameter(boolean ignoreConstructorParameter)
Set whether to ignore constructor parameters.void
setIgnoreFormat(java.util.regex.Pattern pattern)
Set the ignore format for 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.private void
visitOtherTokens(DetailAST ast, int type)
Called to process tokens other thanTokenTypes.VARIABLE_DEF
andTokenTypes.PARAMETER_DEF
.void
visitToken(DetailAST ast)
Called to process a token.-
Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck
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
-
-
-
-
Field Detail
-
MSG_KEY
public static final java.lang.String MSG_KEY
A key is pointing to the warning message text in "messages.properties" file.- See Also:
- Constant Field Values
-
frame
private HiddenFieldCheck.FieldFrame frame
Stack of sets of field names, one for each class of a set of nested classes.
-
ignoreFormat
private java.util.regex.Pattern ignoreFormat
Pattern for names of variables and parameters to ignore.
-
ignoreSetter
private boolean ignoreSetter
Controls whether to check the parameter of a property setter method.
-
setterCanReturnItsClass
private boolean setterCanReturnItsClass
If ignoreSetter is set to true then this variable controls what the setter method can return By default setter must return void. However, is this variable is set to true then setter can also return class in which is declared.
-
ignoreConstructorParameter
private boolean ignoreConstructorParameter
Controls whether to check the parameter of a constructor.
-
ignoreAbstractMethods
private boolean ignoreAbstractMethods
Controls whether to check the parameter of abstract methods.
-
-
Method Detail
-
getDefaultTokens
public int[] getDefaultTokens()
Description copied from class:AbstractCheck
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 classAbstractCheck
- Returns:
- the default tokens
- See Also:
TokenTypes
-
getAcceptableTokens
public int[] getAcceptableTokens()
Description copied from class:AbstractCheck
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.- Specified by:
getAcceptableTokens
in classAbstractCheck
- Returns:
- the token set this check is designed for.
- See Also:
TokenTypes
-
getRequiredTokens
public int[] getRequiredTokens()
Description copied from class:AbstractCheck
The tokens that this check must be registered for.- Specified by:
getRequiredTokens
in classAbstractCheck
- Returns:
- the token set this must be registered for.
- See Also:
TokenTypes
-
beginTree
public void beginTree(DetailAST rootAST)
Description copied from class:AbstractCheck
Called before the starting to process a tree. Ideal place to initialize information that is to be collected whilst processing a tree.- Overrides:
beginTree
in classAbstractCheck
- Parameters:
rootAST
- the root of the tree
-
visitToken
public void visitToken(DetailAST ast)
Description copied from class:AbstractCheck
Called to process a token.- Overrides:
visitToken
in classAbstractCheck
- Parameters:
ast
- the token to process
-
processLambda
private void processLambda(DetailAST ast)
Process a lambda token. Checks whether a lambda parameter shadows a field. Note, that when parameter of lambda expression is untyped, ANTLR parses the parameter as an identifier.- Parameters:
ast
- the lambda token.
-
visitOtherTokens
private void visitOtherTokens(DetailAST ast, int type)
Called to process tokens other thanTokenTypes.VARIABLE_DEF
andTokenTypes.PARAMETER_DEF
.- Parameters:
ast
- token to processtype
- type of the token
-
leaveToken
public void leaveToken(DetailAST ast)
Description copied from class:AbstractCheck
Called after all the child nodes have been process.- Overrides:
leaveToken
in classAbstractCheck
- Parameters:
ast
- the token leaving
-
processVariable
private void processVariable(DetailAST ast)
Process a variable token. Check whether a local variable or parameter shadows a field. Store a field for later comparison with local variables and parameters.- Parameters:
ast
- the variable token.
-
isStaticFieldHiddenFromAnonymousClass
private boolean isStaticFieldHiddenFromAnonymousClass(DetailAST nameAST, java.lang.String name)
Checks whether a static field is hidden from closure.- Parameters:
nameAST
- local variable or parameter.name
- field name.- Returns:
- true if static field is hidden from closure.
-
isIgnoredParam
private boolean isIgnoredParam(DetailAST ast, java.lang.String name)
Checks whether method or constructor parameter is ignored.- Parameters:
ast
- the parameter token.name
- the parameter name.- Returns:
- true if parameter is ignored.
-
isStaticOrInstanceField
private boolean isStaticOrInstanceField(DetailAST ast, java.lang.String name)
Check for static or instance field.- Parameters:
ast
- tokenname
- identifier of token- Returns:
- true if static or instance field
-
isMatchingRegexp
private boolean isMatchingRegexp(java.lang.String name)
Check name by regExp.- Parameters:
name
- string value to check- Returns:
- true is regexp is matching
-
isInStatic
private static boolean isInStatic(DetailAST ast)
Determines whether an AST node is in a static method or static initializer.- Parameters:
ast
- the node to check.- Returns:
- true if ast is in a static method or a static block;
-
isIgnoredSetterParam
private boolean isIgnoredSetterParam(DetailAST ast, java.lang.String name)
Decides whether to ignore an AST node that is the parameter of a setter method, where the property setter method for field 'xyz' has name 'setXyz', one parameter named 'xyz', and return type void (default behavior) or return type is name of the class in which such method is declared (allowed only ifsetSetterCanReturnItsClass(boolean)
is called with value true).- Parameters:
ast
- the AST to check.name
- the name of ast.- Returns:
- true if ast should be ignored because check property ignoreSetter is true and ast is the parameter of a setter method.
-
isSetterMethod
private boolean isSetterMethod(DetailAST aMethodAST, java.lang.String aName)
Determine if a specific method identified by methodAST and a single variable name aName is a setter. This recognition partially depends on mSetterCanReturnItsClass property.- Parameters:
aMethodAST
- AST corresponding to a method callaName
- name of single parameter of this method.- Returns:
- true of false indicating of method is a setter or not.
-
capitalize
private static java.lang.String capitalize(java.lang.String name)
Capitalizes a given property name the way we expect to see it in a setter name.- Parameters:
name
- a property name- Returns:
- capitalized property name
-
isIgnoredConstructorParam
private boolean isIgnoredConstructorParam(DetailAST ast)
Decides whether to ignore an AST node that is the parameter of a constructor.- Parameters:
ast
- the AST to check.- Returns:
- true if ast should be ignored because check property ignoreConstructorParameter is true and ast is a constructor parameter.
-
isIgnoredParamOfAbstractMethod
private boolean isIgnoredParamOfAbstractMethod(DetailAST ast)
Decides whether to ignore an AST node that is the parameter of an abstract method.- Parameters:
ast
- the AST to check.- Returns:
- true if ast should be ignored because check property ignoreAbstractMethods is true and ast is a parameter of abstract methods.
-
setIgnoreFormat
public void setIgnoreFormat(java.util.regex.Pattern pattern)
Set the ignore format for the specified regular expression.- Parameters:
pattern
- a pattern.
-
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.
-
-