Package com.puppycrawl.tools.checkstyle.checks.whitespace

Class WhitespaceBeforeEmptyBodyCheck

java.lang.Object

com.puppycrawl.tools.checkstyle.AbstractAutomaticBean

com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

com.puppycrawl.tools.checkstyle.api.AbstractCheck

com.puppycrawl.tools.checkstyle.checks.whitespace.WhitespaceBeforeEmptyBodyCheck

All Implemented Interfaces:

Configurable, Contextualizable

public class WhitespaceBeforeEmptyBodyCheck
extends AbstractCheck

Checks that a whitespace is present before the opening brace of an empty body.

This check applies to the following tokens: Methods and constructors, Classes, interfaces, enums, and records, Annotation definitions, Loops: while, for, do-while, Lambdas and anonymous classes, Static initializer blocks, Try-catch-finally statements, Synchronized blocks, Switch statements.

A body containing only comments is considered empty by this check.

Since:

13.9.0

Nested Class Summary

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

AbstractAutomaticBean.OutputStreamOptions

Field Summary

Fields

Modifier and Type	Field	Description
static final String	MSG_KEY	A key is pointing to the warning message text in "messages.properties" file.

Constructor Summary

Constructors

Constructor	Description
WhitespaceBeforeEmptyBodyCheck()	Creates a new WhitespaceBeforeEmptyBodyCheck instance.

Method Summary

Modifier and Type	Method	Description
private static DetailAST	descendToLeafNode(DetailAST token)	Return the last nested child of the token.
private static DetailAST	findOpeningBrace(DetailAST ast)	Returns left curly token for an ast.
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 static boolean	isBodyEmpty(DetailAST lcurly)	Checks if the body is empty.
private static boolean	isSpaceBetweenTokens(DetailAST firstToken, DetailAST secondToken)	Checks if space exists between first and second token.
private static boolean	precededByWhiteSpace(DetailAST lcurly)	Checks if the opening brace is preceded by whitespace.
void	visitToken(DetailAST ast)	Called to process a token.

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

beginTree, clearViolations, destroy, finishTree, getFileContents, getFilePath, 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.AbstractAutomaticBean

configure, contextualize, getConfiguration, setupChild

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

MSG_KEY

public static final String MSG_KEY

A key is pointing to the warning message text in "messages.properties" file.

See Also:

• Constant Field Values

Constructor Details

WhitespaceBeforeEmptyBodyCheck

public WhitespaceBeforeEmptyBodyCheck()

Creates a new WhitespaceBeforeEmptyBodyCheck instance.

Method Details

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

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

findOpeningBrace

@Nullable
private static DetailAST findOpeningBrace(DetailAST ast)

Returns left curly token for an ast.

Parameters:

ast - the AST to get brace token for

Returns:

the left curly token, or null if the construct has no-body

precededByWhiteSpace

private static boolean precededByWhiteSpace(DetailAST lcurly)

Checks if the opening brace is preceded by whitespace.

Parameters:

lcurly - token representing the opening brace

Returns:

true if preceded by whitespace

descendToLeafNode

private static DetailAST descendToLeafNode(DetailAST token)

Return the last nested child of the token.

Parameters:

token - the ast token

Returns:

nested child

isBodyEmpty

private static boolean isBodyEmpty(DetailAST lcurly)

Checks if the body is empty.

Parameters:

lcurly - the token representing the opening brace

Returns:

true if the body is empty

isSpaceBetweenTokens

private static boolean isSpaceBetweenTokens(DetailAST firstToken,
 DetailAST secondToken)

Checks if space exists between first and second token.

Parameters:

firstToken - token in ast which is behind second token

secondToken - token next to firstToken

Returns:

true if space exists between first and second tokens