com.puppycrawl.tools.checkstyle.checks.whitespace

Class NoWhitespaceAfterCheck

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.whitespace.NoWhitespaceAfterCheck

All Implemented Interfaces:

Configurable, Contextualizable

public class NoWhitespaceAfterCheck
extends AbstractCheck

Checks that there is no whitespace after a token. More specifically, it checks that it is not followed by whitespace, or (if linebreaks are allowed) all characters on the line after are whitespace. To forbid linebreaks after a token, set property allowLineBreaks to false.

The check processes ARRAY_DECLARATOR and INDEX_OP tokens specially from other tokens. Actually it is checked that there is no whitespace before this tokens, not after them. Space after the ANNOTATIONS before ARRAY_DECLARATOR and INDEX_OP will be ignored.

• Property allowLineBreaks - Control whether whitespace is allowed if the token is at a linebreak. Type is boolean. Default value is true.
• Property tokens - tokens to check Type is java.lang.String[]. Validation type is tokenSet. Default value is: ARRAY_INIT, AT, INC, DEC, UNARY_MINUS, UNARY_PLUS, BNOT, LNOT, DOT, ARRAY_DECLARATOR, INDEX_OP.

To configure the check:

 <module name="NoWhitespaceAfter"/>
 

To configure the check to forbid linebreaks after a DOT token:

 <module name="NoWhitespaceAfter">
   <property name="tokens" value="DOT"/>
   <property name="allowLineBreaks" value="false"/>
 </module>
 

If the annotation is between the type and the array, the check will skip validation for spaces:

 public void foo(final char @NotNull [] param) {} // No violation
 

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

• ws.followed

Since:

3.0

Nested Class Summary

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

AutomaticBean.OutputStreamOptions

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	allowLineBreaks Control whether whitespace is allowed if the token is at a linebreak.
static java.lang.String	MSG_KEY A key is pointing to the warning message text in "messages.properties" file.

Constructor Summary

Constructors

Constructor and Description
NoWhitespaceAfterCheck()

Method Summary

Modifier and Type	Method and Description
int[]	getAcceptableTokens() The configurable token set.
private static DetailAST	getArrayDeclaratorPreviousElement(DetailAST ast) Returns proper argument for getPositionAfter method, it is a token after ARRAY_DECLARATOR, in can be RBRACK, IDENT or an array type definition (literal).
int[]	getDefaultTokens() Returns the default token a check is interested in.
private static DetailAST	getIdentLastToken(DetailAST ast) Gets leftmost token of identifier.
private static DetailAST	getIndexOpPreviousElement(DetailAST ast) Gets previous node for INDEX_OP token for usage in getPositionAfter method, it is a simplified copy of getArrayDeclaratorPreviousElement method.
private static int	getPositionAfter(DetailAST ast) Gets position after token (place of possible redundant whitespace).
private static DetailAST	getPrecedingDot(DetailAST leftBracket) Gets the dot preceding a class member array index operation or class reference.
private static DetailAST	getPreviousElementOfMultiDimArray(DetailAST leftBracket) Gets the previous element of a second or higher dimension of an array declaration or initialization.
private static DetailAST	getPreviousNodeWithParentOfTypeAst(DetailAST ast, DetailAST parent) Finds previous node by text order for an array declarator, which parent type is TYPE.
int[]	getRequiredTokens() The tokens that this check must be registered for.
private static DetailAST	getTypeLastNode(DetailAST ast) Searches parameter node for a type node.
private static DetailAST	getWhitespaceFollowedNode(DetailAST ast) For a visited ast node returns node that should be checked for not being followed by whitespace.
private boolean	hasTrailingWhitespace(DetailAST ast, int whitespaceColumnNo, int whitespaceLineNo) Checks if there is unwanted whitespace after the visited node.
void	setAllowLineBreaks(boolean allowLineBreaks) Setter to control whether whitespace is allowed if the token is at a linebreak.
private static boolean	shouldCheckWhitespaceAfter(DetailAST ast) Returns whether whitespace after a visited node should be checked.
void	visitToken(DetailAST ast) Called to process a token.

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

beginTree, clearViolations, destroy, finishTree, getFileContents, getLine, getLineCodePoints, getLines, getTabWidth, getTokenNames, getViolations, init, isCommentNodesRequired, leaveToken, 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_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

allowLineBreaks

private boolean allowLineBreaks

Control whether whitespace is allowed if the token is at a linebreak.

Constructor Detail

NoWhitespaceAfterCheck

public NoWhitespaceAfterCheck()

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 class AbstractCheck

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 class AbstractCheck

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 class AbstractCheck

Returns:

the token set this must be registered for.

See Also:

TokenTypes

setAllowLineBreaks

public void setAllowLineBreaks(boolean allowLineBreaks)

Setter to control whether whitespace is allowed if the token is at a linebreak.

Parameters:

allowLineBreaks - whether whitespace should be flagged at linebreaks.

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

getWhitespaceFollowedNode

private static DetailAST getWhitespaceFollowedNode(DetailAST ast)

For a visited ast node returns node that should be checked for not being followed by whitespace.

Parameters:

ast - , visited node.

Returns:

node before ast.

shouldCheckWhitespaceAfter

private static boolean shouldCheckWhitespaceAfter(DetailAST ast)

Returns whether whitespace after a visited node should be checked. For example, whitespace is not allowed between a type and an array declarator (returns true), except when there is an annotation in between the type and array declarator (returns false).

Parameters:

ast - the visited node

Returns:

true if whitespace after ast should be checked

getPositionAfter

private static int getPositionAfter(DetailAST ast)

Gets position after token (place of possible redundant whitespace).

Parameters:

ast - Node representing token.

Returns:

position after token.

hasTrailingWhitespace

private boolean hasTrailingWhitespace(DetailAST ast,
                                      int whitespaceColumnNo,
                                      int whitespaceLineNo)

Checks if there is unwanted whitespace after the visited node.

Parameters:

ast - , visited node.

whitespaceColumnNo - , column number of a possible whitespace.

whitespaceLineNo - , line number of a possible whitespace.

Returns:

true if whitespace found.

getArrayDeclaratorPreviousElement

private static DetailAST getArrayDeclaratorPreviousElement(DetailAST ast)

Returns proper argument for getPositionAfter method, it is a token after ARRAY_DECLARATOR, in can be RBRACK, IDENT or an array type definition (literal).

Parameters:

ast - , ARRAY_DECLARATOR node.

Returns:

previous node by text order.

Throws:

java.lang.IllegalStateException - if an unexpected token type is encountered.

getPreviousElementOfMultiDimArray

private static DetailAST getPreviousElementOfMultiDimArray(DetailAST leftBracket)

Gets the previous element of a second or higher dimension of an array declaration or initialization.

Parameters:

leftBracket - the token to get previous element of

Returns:

the previous element

getIndexOpPreviousElement

private static DetailAST getIndexOpPreviousElement(DetailAST ast)

Gets previous node for INDEX_OP token for usage in getPositionAfter method, it is a simplified copy of getArrayDeclaratorPreviousElement method.

Parameters:

ast - , INDEX_OP node.

Returns:

previous node by text order.

getTypeLastNode

private static DetailAST getTypeLastNode(DetailAST ast)

Searches parameter node for a type node. Returns it or its last node if it has an extended structure.

Parameters:

ast - , subject node.

Returns:

type node.

getPreviousNodeWithParentOfTypeAst

private static DetailAST getPreviousNodeWithParentOfTypeAst(DetailAST ast,
                                                            DetailAST parent)

Finds previous node by text order for an array declarator, which parent type is TYPE.

Parameters:

ast - , array declarator node.

parent - , its parent node.

Returns:

previous node by text order.

getIdentLastToken

private static DetailAST getIdentLastToken(DetailAST ast)

Gets leftmost token of identifier.

Parameters:

ast - , token possibly possessing an identifier.

Returns:

leftmost token of identifier.

getPrecedingDot

private static DetailAST getPrecedingDot(DetailAST leftBracket)

Gets the dot preceding a class member array index operation or class reference.

Parameters:

leftBracket - the ast we are checking

Returns:

dot preceding the left bracket