RequireThisCheck (checkstyle 9.3 API)

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.RequireThisCheck

All Implemented Interfaces:: Configurable, Contextualizable

public class RequireThisCheck
extends AbstractCheck

Checks that references to instance variables and methods of the present object are explicitly of the form "this.varName" or "this.methodName(args)" and that those references don't rely on the default behavior when "this." is absent.

Warning: the Check is very controversial if 'validateOnlyOverlapping' option is set to 'false' and not that actual nowadays.

Rationale:

The same notation/habit for C++ and Java (C++ have global methods, so having "this." do make sense in it to distinguish call of method of class instead of global).
Non-IDE development (ease of refactoring, some clearness to distinguish static and non-static methods).

Limitations: Nothing is currently done about static variables or catch-blocks. Static methods invoked on a class name seem to be OK; both the class name and the method name have a DOT parent. Non-static methods invoked on either this or a variable name seem to be OK, likewise.

Property checkFields - Control whether to check references to fields. Type is boolean. Default value is true.
Property checkMethods - Control whether to check references to methods. Type is boolean. Default value is true.
Property validateOnlyOverlapping - Control whether to check only overlapping by variables or arguments. Type is boolean. Default value is true.

To configure the default check:

 <module name="RequireThis"/>

Example:

 public class Test {
   private int a;
   private int b;
   private int c;

   public Test(int a) {
     // overlapping by constructor argument
     this.a = a;       // OK, this keyword used
     b = 0;            // OK, no overlap
     foo(5);           // OK
   }

   public void foo(int c) {
     // overlapping by method argument
     c = c;            // violation, reference to instance variable "c" requires "this"
   }
 }

To configure the check for fields only:

 <module name="RequireThis">
   <property name="checkMethods" value="false"/>
 </module>

Example:

 public class Test {
   private int a;
   private int b;
   private int c;

   public Test(int a) {
     // overlapping by constructor argument
     this.a = a;       // OK, this keyword used
     b = 0;            // OK, no overlap
     foo(5);           // OK, no validation for methods
   }

   public void foo(int c) {
     // overlapping by method argument
     c = c;            // violation, reference to instance variable "c" requires "this"
   }
 }

To configure the check for methods only:

 <module name="RequireThis">
   <property name="checkFields" value="false"/>
 </module>

Example:

 public class Test {
   private int a;
   private int b;
   private int c;

   public Test(int a) {
     // overlapping by constructor argument
     this.a = a;       // OK, no validation for fields
     b = 0;            // OK, no validation for fields
     foo(5);           // OK, no overlap
   }

   public void foo(int c) {
     // overlapping by method argument
     c = c;            // OK, no validation for fields
   }
 }

Note that method call foo(5) does not raise a violation because methods cannot be overlapped in java.

To configure the check to validate for non-overlapping fields and methods:

 <module name="RequireThis">
   <property name="validateOnlyOverlapping" value="false"/>
 </module>

Example:

 public class Test {
   private int a;
   private int b;
   private int c;

   public Test(int a) {
     // overlapping by constructor argument
     this.a = a;       // OK, no validation for fields
     b = 0;            // violation, reference to instance variable "b" requires "this"
     foo(5);           // violation, method call "foo(5)" requires "this"
   }

   public void foo(int c) {
     // overlapping by method argument
     c = c;            // violation, reference to instance variable "c" requires "this"
   }
 }

Please, be aware of the following logic, which is implemented in the check:

1) If you arrange 'this' in your code on your own, the check will not raise violation for variables which use 'this' to reference a class field, for example:

 public class C {
   private int scale;
   private int x;

   public void foo(int scale) {
     scale = this.scale;      // no violation

     if (scale > 0) {
       scale = -scale;        // no violation
     }
     x *= scale;
   }
 }

2) If method parameter is returned from the method, the check will not raise violation for returned variable/parameter, for example:

 public class D {
   private String prefix;

   public String modifyPrefix(String prefix) {
     prefix = "^" + prefix + "$";  // no violation, because method parameter is returned
     return prefix;
   }
 }

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

require.this.method
require.this.variable

Since:: 3.4

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`private static class`	`RequireThisCheck.AbstractFrame` A declaration frame.
`private static class`	`RequireThisCheck.AnonymousClassFrame` An anonymous class frame; holds instance variable names.
`private static class`	`RequireThisCheck.BlockFrame` A frame initiated on entering a statement list; holds local variable names.
`private static class`	`RequireThisCheck.CatchFrame` A frame initiated on entering a catch block; holds local catch variable names.
`private static class`	`RequireThisCheck.ClassFrame` A frame initiated at class, enum or interface definition; holds instance variable names.
`private static class`	`RequireThisCheck.ConstructorFrame` A frame initiated at constructor definition.
`private static class`	`RequireThisCheck.ForFrame` A frame initiated on entering a for block; holds local for variable names.
`private static class`	`RequireThisCheck.FrameType` An AbstractFrame type.
`private static class`	`RequireThisCheck.MethodFrame` A frame initiated at method definition; holds a method definition token.

Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean
AutomaticBean.OutputStreamOptions

Field Summary

Fields
Modifier and Type	Field and Description
`private static java.util.Set<java.lang.Integer>`	`ASSIGN_TOKENS` Set of all assign tokens.
`private boolean`	`checkFields` Control whether to check references to fields.
`private boolean`	`checkMethods` Control whether to check references to methods.
`private static java.util.Set<java.lang.Integer>`	`COMPOUND_ASSIGN_TOKENS` Set of all compound assign tokens.
`private java.util.Deque<RequireThisCheck.AbstractFrame>`	`current` Frame for the currently processed AST.
`private static java.util.Set<java.lang.Integer>`	`DECLARATION_TOKENS` Set of all declaration tokens.
`private java.util.Map<DetailAST,RequireThisCheck.AbstractFrame>`	`frames` Tree of all the parsed frames.
`static java.lang.String`	`MSG_METHOD` A key is pointing to the warning message text in "messages.properties" file.
`static java.lang.String`	`MSG_VARIABLE` A key is pointing to the warning message text in "messages.properties" file.
`private boolean`	`validateOnlyOverlapping` Control whether to check only overlapping by variables or arguments.

Constructor Summary

Constructors
Constructor and Description

RequireThisCheck()

Constructors
Constructor and Description
`RequireThisCheck()`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`beginTree(DetailAST rootAST)` Called before the starting to process a tree.
`private boolean`	`canAssignValueToClassField(DetailAST ast)` Checks whether a value can be assigned to a field.
`private boolean`	`canBeReferencedFromStaticContext(DetailAST ident)` Checks whether a field can be referenced from a static context.
`private static void`	`collectDeclarations(java.util.Deque<RequireThisCheck.AbstractFrame> frameStack, DetailAST ast)` Parses the next AST for declarations.
`private static void`	`collectVariableDeclarations(DetailAST ast, RequireThisCheck.AbstractFrame frame)` Collects variable declarations.
`private void`	`endCollectingDeclarations(java.util.Queue<RequireThisCheck.AbstractFrame> frameStack, DetailAST ast)` Ends parsing of the AST for declarations.
`private RequireThisCheck.AbstractFrame`	`findClassFrame(DetailAST name, boolean lookForMethod)` Find the class frame containing declaration.
`private RequireThisCheck.AbstractFrame`	`findFrame(DetailAST name, boolean lookForMethod)` Find frame containing declaration.
`private static RequireThisCheck.AbstractFrame`	`findFrame(RequireThisCheck.AbstractFrame frame, DetailAST name, boolean lookForMethod)` Find frame containing declaration.
`int[]`	`getAcceptableTokens()` The configurable token set.
`private static java.util.Set<DetailAST>`	`getAllTokensOfType(DetailAST ast, int tokenType)` Collects all tokens of specific type starting with the current ast node.
`private static java.util.Set<DetailAST>`	`getAllTokensOfType(DetailAST ast, int tokenType, int endLineNumber)` Collects all tokens of specific type starting with the current ast node and which line number is lower or equal to the end line number.
`private static java.util.Set<DetailAST>`	`getAllTokensWhichAreEqualToCurrent(DetailAST ast, DetailAST token, int endLineNumber)` Collects all tokens which are equal to current token starting with the current ast node and which line number is lower or equal to the end line number.
`private static DetailAST`	`getBlockEndToken(DetailAST blockNameIdent, DetailAST blockStartToken)` Returns the token which ends the code block.
`private RequireThisCheck.AbstractFrame`	`getClassFrameWhereViolationIsFound(DetailAST ast)` Returns the class frame where violation is found (where the field is used without 'this') or null otherwise.
`private static DetailAST`	`getCodeBlockDefinitionToken(DetailAST ident)` Returns code block definition token for current identifier.
`int[]`	`getDefaultTokens()` Returns the default token a check is interested in.
`private RequireThisCheck.AbstractFrame`	`getFieldWithoutThis(DetailAST ast, int parentType)` Returns the frame where the field is declared, if the given field is used without 'this', and null otherwise.
`private RequireThisCheck.AbstractFrame`	`getMethodWithoutThis(DetailAST ast)` Returns the frame where the method is declared, if the given method is used without 'this' and null otherwise.
`private java.lang.String`	`getNearestClassFrameName()` Gets the name of the nearest parent ClassFrame.
`int[]`	`getRequiredTokens()` The tokens that this check must be registered for.
`private static boolean`	`isAnonymousClassDef(DetailAST ast)` Whether the AST is a definition of an anonymous class.
`private static boolean`	`isAssignToken(int tokenType)` Check that token is related to assign tokens.
`private static boolean`	`isAstInside(DetailAST tree, DetailAST ast)` Checks if the given `ast` is equal to the `tree` or a child of it.
`private static boolean`	`isAstSimilar(DetailAST left, DetailAST right)` Checks if 2 AST are similar by their type and text.
`private static boolean`	`isCompoundAssignToken(int tokenType)` Check that token is related to compound assign tokens.
`private static boolean`	`isDeclarationToken(int parentType)` Check that token is related to Definition tokens.
`private static boolean`	`isInCompactConstructor(DetailAST ast)` Return whether ast is in a COMPACT_CTOR_DEF.
`private static boolean`	`isInExpression(DetailAST ast)` Checks ast parent is in expression.
`private static boolean`	`isInsideConstructorFrame(RequireThisCheck.AbstractFrame frame)` Checks whether a field usage frame is inside constructor frame.
`private static boolean`	`isLambdaParameter(DetailAST ast)` Checks if the token is a Lambda parameter.
`private boolean`	`isOverlappingByArgument(DetailAST ast)` Checks whether an overlapping by method or constructor argument takes place.
`private boolean`	`isOverlappingByLocalVariable(DetailAST ast)` Checks whether an overlapping by local variable takes place.
`private static boolean`	`isReturnedVariable(RequireThisCheck.AbstractFrame currentFrame, DetailAST ident)` Checks whether the current variable is returned from the method.
`private static boolean`	`isUserDefinedArrangementOfThis(RequireThisCheck.AbstractFrame currentFrame, DetailAST ident)` Checks whether user arranges 'this' for variable in method, constructor, or block on his own.
`void`	`leaveToken(DetailAST ast)` Called after all the child nodes have been process.
`private void`	`logViolation(java.lang.String msgKey, DetailAST ast, RequireThisCheck.AbstractFrame frame)` Helper method to log a Violation.
`private void`	`processIdent(DetailAST ast)` Checks if a given IDENT is method call or field name which requires explicit `this` qualifier.
`void`	`setCheckFields(boolean checkFields)` Setter to control whether to check references to fields.
`void`	`setCheckMethods(boolean checkMethods)` Setter to control whether to check references to methods.
`void`	`setValidateOnlyOverlapping(boolean validateOnlyOverlapping)` Setter to control whether to check only overlapping by variables or arguments.
`void`	`visitToken(DetailAST ast)` Called to process a token.

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck
clearViolations, destroy, finishTree, getFileContents, getLine, getLineCodePoints, getLines, getTabWidth, getTokenNames, getViolations, init, isCommentNodesRequired, 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_METHOD
```
public static final java.lang.String MSG_METHOD
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_VARIABLE
```
public static final java.lang.String MSG_VARIABLE
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - DECLARATION_TOKENS
```
private static final java.util.Set<java.lang.Integer> DECLARATION_TOKENS
```
    Set of all declaration tokens.
  - ASSIGN_TOKENS
```
private static final java.util.Set<java.lang.Integer> ASSIGN_TOKENS
```
    Set of all assign tokens.
  - COMPOUND_ASSIGN_TOKENS
```
private static final java.util.Set<java.lang.Integer> COMPOUND_ASSIGN_TOKENS
```
    Set of all compound assign tokens.
  - current
```
private final java.util.Deque<RequireThisCheck.AbstractFrame> current
```
    Frame for the currently processed AST.
  - frames
```
private java.util.Map<DetailAST,RequireThisCheck.AbstractFrame> frames
```
    Tree of all the parsed frames.
  - checkFields
```
private boolean checkFields
```
    Control whether to check references to fields.
  - checkMethods
```
private boolean checkMethods
```
    Control whether to check references to methods.
  - validateOnlyOverlapping
```
private boolean validateOnlyOverlapping
```
    Control whether to check only overlapping by variables or arguments.
- Constructor Detail
  - RequireThisCheck
```
public RequireThisCheck()
```
- Method Detail
  - setCheckFields
```
public void setCheckFields(boolean checkFields)
```
    Setter to control whether to check references to fields.
    
    Parameters:
    
    checkFields - should we check fields usage or not.
  - setCheckMethods
```
public void setCheckMethods(boolean checkMethods)
```
    Setter to control whether to check references to methods.
    
    Parameters:
    
    checkMethods - should we check methods usage or not.
  - setValidateOnlyOverlapping
```
public void setValidateOnlyOverlapping(boolean validateOnlyOverlapping)
```
    Setter to control whether to check only overlapping by variables or arguments.
    
    Parameters:
    
    validateOnlyOverlapping - should we check only overlapping by variables or arguments.
  - 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 class AbstractCheck
    
    Returns:
    
    the default tokens
    
    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 class AbstractCheck
    
    Returns:
    
    the token set this must be registered for.
    
    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 class AbstractCheck
    
    Returns:
    
    the token set this check is designed 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 class AbstractCheck
    
    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 class AbstractCheck
    
    Parameters:
    
    ast - the token to process
  - leaveToken
```
public void leaveToken(DetailAST ast)
```
    Description copied from class: AbstractCheck
    
    Called after all the child nodes have been process.
    
    Overrides:
    
    leaveToken in class AbstractCheck
    
    Parameters:
    
    ast - the token leaving
  - processIdent
```
private void processIdent(DetailAST ast)
```
    Checks if a given IDENT is method call or field name which requires explicit this qualifier.
    
    Parameters:
    
    ast - IDENT to check.
  - logViolation
```
private void logViolation(java.lang.String msgKey,
                          DetailAST ast,
                          RequireThisCheck.AbstractFrame frame)
```
    Helper method to log a Violation.
    
    Parameters:
    
    msgKey - key to locale message format.
    
    ast - a node to get line id column numbers associated with the message.
    
    frame - the class frame where the violation is found.
  - getFieldWithoutThis
```
private RequireThisCheck.AbstractFrame getFieldWithoutThis(DetailAST ast,
                                                           int parentType)
```
    Returns the frame where the field is declared, if the given field is used without 'this', and null otherwise.
    
    Parameters:
    
    ast - field definition ast token.
    
    parentType - type of the parent.
    
    Returns:
    
    the frame where the field is declared, if the given field is used without 'this' and null otherwise.
  - isInCompactConstructor
```
private static boolean isInCompactConstructor(DetailAST ast)
```
    Return whether ast is in a COMPACT_CTOR_DEF.
    
    Parameters:
    
    ast - The token to check
    
    Returns:
    
    true if ast is in a COMPACT_CTOR_DEF, false otherwise
  - collectDeclarations
```
private static void collectDeclarations(java.util.Deque<RequireThisCheck.AbstractFrame> frameStack,
                                        DetailAST ast)
```
    Parses the next AST for declarations.
    
    Parameters:
    
    frameStack - stack containing the FrameTree being built.
    
    ast - AST to parse.
  - collectVariableDeclarations
```
private static void collectVariableDeclarations(DetailAST ast,
                                                RequireThisCheck.AbstractFrame frame)
```
    Collects variable declarations.
    
    Parameters:
    
    ast - variable token.
    
    frame - current frame.
  - endCollectingDeclarations
```
private void endCollectingDeclarations(java.util.Queue<RequireThisCheck.AbstractFrame> frameStack,
                                       DetailAST ast)
```
    Ends parsing of the AST for declarations.
    
    Parameters:
    
    frameStack - Stack containing the FrameTree being built.
    
    ast - AST that was parsed.
  - isAnonymousClassDef
```
private static boolean isAnonymousClassDef(DetailAST ast)
```
    Whether the AST is a definition of an anonymous class.
    
    Parameters:
    
    ast - the AST to process.
    
    Returns:
    
    true if the AST is a definition of an anonymous class.
  - getClassFrameWhereViolationIsFound
```
private RequireThisCheck.AbstractFrame getClassFrameWhereViolationIsFound(DetailAST ast)
```
    Returns the class frame where violation is found (where the field is used without 'this') or null otherwise.
    
    Parameters:
    
    ast - IDENT ast to check.
    
    Returns:
    
    the class frame where violation is found or null otherwise.
  - isInExpression
```
private static boolean isInExpression(DetailAST ast)
```
    Checks ast parent is in expression.
    
    Parameters:
    
    ast - token to check
    
    Returns:
    
    true if token is part of expression, false otherwise
  - isUserDefinedArrangementOfThis
```
private static boolean isUserDefinedArrangementOfThis(RequireThisCheck.AbstractFrame currentFrame,
                                                      DetailAST ident)
```
    Checks whether user arranges 'this' for variable in method, constructor, or block on his own.
    
    Parameters:
    
    currentFrame - current frame.
    
    ident - ident token.
    
    Returns:
    
    true if user arranges 'this' for variable in method, constructor, or block on his own.
  - getBlockEndToken
```
private static DetailAST getBlockEndToken(DetailAST blockNameIdent,
                                          DetailAST blockStartToken)
```
    Returns the token which ends the code block.
    
    Parameters:
    
    blockNameIdent - block name identifier.
    
    blockStartToken - token which starts the block.
    
    Returns:
    
    the token which ends the code block.
  - isReturnedVariable
```
private static boolean isReturnedVariable(RequireThisCheck.AbstractFrame currentFrame,
                                          DetailAST ident)
```
    Checks whether the current variable is returned from the method.
    
    Parameters:
    
    currentFrame - current frame.
    
    ident - variable ident token.
    
    Returns:
    
    true if the current variable is returned from the method.
  - isAstInside
```
private static boolean isAstInside(DetailAST tree,
                                   DetailAST ast)
```
    Checks if the given ast is equal to the tree or a child of it.
    
    Parameters:
    
    tree - The tree to search.
    
    ast - The AST to look for.
    
    Returns:
    
    true if the ast was found.
  - canBeReferencedFromStaticContext
```
private boolean canBeReferencedFromStaticContext(DetailAST ident)
```
    Checks whether a field can be referenced from a static context.
    
    Parameters:
    
    ident - ident token.
    
    Returns:
    
    true if field can be referenced from a static context.
  - getCodeBlockDefinitionToken
```
private static DetailAST getCodeBlockDefinitionToken(DetailAST ident)
```
    Returns code block definition token for current identifier.
    
    Parameters:
    
    ident - ident token.
    
    Returns:
    
    code block definition token for current identifier or null if code block definition was not found.
  - canAssignValueToClassField
```
private boolean canAssignValueToClassField(DetailAST ast)
```
    Checks whether a value can be assigned to a field. A value can be assigned to a final field only in constructor block. If there is a method block, value assignment can be performed only to non final field.
    
    Parameters:
    
    ast - an identifier token.
    
    Returns:
    
    true if a value can be assigned to a field.
  - isInsideConstructorFrame
```
private static boolean isInsideConstructorFrame(RequireThisCheck.AbstractFrame frame)
```
    Checks whether a field usage frame is inside constructor frame.
    
    Parameters:
    
    frame - frame, where field is used.
    
    Returns:
    
    true if the field usage frame is inside constructor frame.
  - isOverlappingByArgument
```
private boolean isOverlappingByArgument(DetailAST ast)
```
    Checks whether an overlapping by method or constructor argument takes place.
    
    Parameters:
    
    ast - an identifier.
    
    Returns:
    
    true if an overlapping by method or constructor argument takes place.
  - isOverlappingByLocalVariable
```
private boolean isOverlappingByLocalVariable(DetailAST ast)
```
    Checks whether an overlapping by local variable takes place.
    
    Parameters:
    
    ast - an identifier.
    
    Returns:
    
    true if an overlapping by local variable takes place.
  - getAllTokensOfType
```
private static java.util.Set<DetailAST> getAllTokensOfType(DetailAST ast,
                                                           int tokenType)
```
    Collects all tokens of specific type starting with the current ast node.
    
    Parameters:
    
    ast - ast node.
    
    tokenType - token type.
    
    Returns:
    
    a set of all tokens of specific type starting with the current ast node.
  - getAllTokensOfType
```
private static java.util.Set<DetailAST> getAllTokensOfType(DetailAST ast,
                                                           int tokenType,
                                                           int endLineNumber)
```
    Collects all tokens of specific type starting with the current ast node and which line number is lower or equal to the end line number.
    
    Parameters:
    
    ast - ast node.
    
    tokenType - token type.
    
    endLineNumber - end line number.
    
    Returns:
    
    a set of all tokens of specific type starting with the current ast node and which line number is lower or equal to the end line number.
  - getAllTokensWhichAreEqualToCurrent
```
private static java.util.Set<DetailAST> getAllTokensWhichAreEqualToCurrent(DetailAST ast,
                                                                           DetailAST token,
                                                                           int endLineNumber)
```
    Collects all tokens which are equal to current token starting with the current ast node and which line number is lower or equal to the end line number.
    
    Parameters:
    
    ast - ast node.
    
    token - token.
    
    endLineNumber - end line number.
    
    Returns:
    
    a set of tokens which are equal to current token starting with the current ast node and which line number is lower or equal to the end line number.
  - getMethodWithoutThis
```
private RequireThisCheck.AbstractFrame getMethodWithoutThis(DetailAST ast)
```
    Returns the frame where the method is declared, if the given method is used without 'this' and null otherwise.
    
    Parameters:
    
    ast - the IDENT ast of the name to check.
    
    Returns:
    
    the frame where the method is declared, if the given method is used without 'this' and null otherwise.
  - findClassFrame
```
private RequireThisCheck.AbstractFrame findClassFrame(DetailAST name,
                                                      boolean lookForMethod)
```
    Find the class frame containing declaration.
    
    Parameters:
    
    name - IDENT ast of the declaration to find.
    
    lookForMethod - whether we are looking for a method name.
    
    Returns:
    
    AbstractFrame containing declaration or null.
  - findFrame
```
private RequireThisCheck.AbstractFrame findFrame(DetailAST name,
                                                 boolean lookForMethod)
```
    Find frame containing declaration.
    
    Parameters:
    
    name - IDENT ast of the declaration to find.
    
    lookForMethod - whether we are looking for a method name.
    
    Returns:
    
    AbstractFrame containing declaration or null.
  - findFrame
```
private static RequireThisCheck.AbstractFrame findFrame(RequireThisCheck.AbstractFrame frame,
                                                        DetailAST name,
                                                        boolean lookForMethod)
```
    Find frame containing declaration.
    
    Parameters:
    
    frame - The parent frame to searching in.
    
    name - IDENT ast of the declaration to find.
    
    lookForMethod - whether we are looking for a method name.
    
    Returns:
    
    AbstractFrame containing declaration or null.
  - isDeclarationToken
```
private static boolean isDeclarationToken(int parentType)
```
    Check that token is related to Definition tokens.
    
    Parameters:
    
    parentType - token Type.
    
    Returns:
    
    true if token is related to Definition Tokens.
  - isAssignToken
```
private static boolean isAssignToken(int tokenType)
```
    Check that token is related to assign tokens.
    
    Parameters:
    
    tokenType - token type.
    
    Returns:
    
    true if token is related to assign tokens.
  - isCompoundAssignToken
```
private static boolean isCompoundAssignToken(int tokenType)
```
    Check that token is related to compound assign tokens.
    
    Parameters:
    
    tokenType - token type.
    
    Returns:
    
    true if token is related to compound assign tokens.
  - getNearestClassFrameName
```
private java.lang.String getNearestClassFrameName()
```
    Gets the name of the nearest parent ClassFrame.
    
    Returns:
    
    the name of the nearest parent ClassFrame.
  - isLambdaParameter
```
private static boolean isLambdaParameter(DetailAST ast)
```
    Checks if the token is a Lambda parameter.
    
    Parameters:
    
    ast - the DetailAST value of the token to be checked
    
    Returns:
    
    true if the token is a Lambda parameter
  - isAstSimilar
```
private static boolean isAstSimilar(DetailAST left,
                                    DetailAST right)
```
    Checks if 2 AST are similar by their type and text.
    
    Parameters:
    
    left - The first AST to check.
    
    right - The second AST to check.
    
    Returns:
    
    true if they are similar.

Class RequireThisCheck

Nested Class Summary

Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

Field Summary

Constructor Summary

Method Summary

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

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

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

Methods inherited from class java.lang.Object

Field Detail

MSG_METHOD

MSG_VARIABLE

DECLARATION_TOKENS

ASSIGN_TOKENS

COMPOUND_ASSIGN_TOKENS

current

frames

checkFields

checkMethods

validateOnlyOverlapping

Constructor Detail

RequireThisCheck

Method Detail

setCheckFields

setCheckMethods

setValidateOnlyOverlapping

getDefaultTokens

getRequiredTokens

getAcceptableTokens

beginTree

visitToken

leaveToken

processIdent

logViolation

getFieldWithoutThis

isInCompactConstructor

collectDeclarations

collectVariableDeclarations

endCollectingDeclarations

isAnonymousClassDef

getClassFrameWhereViolationIsFound

isInExpression

isUserDefinedArrangementOfThis

getBlockEndToken

isReturnedVariable

isAstInside

canBeReferencedFromStaticContext

getCodeBlockDefinitionToken

canAssignValueToClassField

isInsideConstructorFrame

isOverlappingByArgument

isOverlappingByLocalVariable

getAllTokensOfType

getAllTokensOfType

getAllTokensWhichAreEqualToCurrent

getMethodWithoutThis

findClassFrame

findFrame

findFrame

isDeclarationToken

isAssignToken

isCompoundAssignToken

getNearestClassFrameName

isLambdaParameter

isAstSimilar