Package com.puppycrawl.tools.checkstyle.checks.coding

Class MatchXpathCheck

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.coding.MatchXpathCheck

All Implemented Interfaces:

Configurable, Contextualizable

public class MatchXpathCheck
extends AbstractCheck

Evaluates Xpath query and report violation on all matching AST nodes. This check allows user to implement custom checks using Xpath. If Xpath query is not specified explicitly, then the check does nothing.

It is recommended to define custom message for violation to explain what is not allowed and what to use instead, default message might be too abstract. To customize a message you need to add message element with matchxpath.match as key attribute and desired message as value attribute.

Please read more about Xpath syntax at Xpath Syntax. Information regarding Xpath functions can be found at XSLT/XPath Reference. Note, that @text attribute can be used only with token types that are listed in XpathUtil.

• Property query - Specify Xpath query. Type is java.lang.String. Default value is "".

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

• matchxpath.match

Since:

8.39

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 provided by user.
private String	query	Specify Xpath query.
private net.sf.saxon.sxpath.XPathExpression	xpathExpression	Xpath expression.

Constructor Summary

Constructors

Constructor	Description
MatchXpathCheck()

Method Summary

Modifier and Type	Method	Description
void	beginTree(DetailAST rootAST)	Called before the starting to process a tree.
private List<DetailAST>	findMatchingNodesByXpathQuery(DetailAST rootAST)	Find nodes that match query.
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.
boolean	isCommentNodesRequired()	Whether comment nodes are required or not.
void	setQuery(String query)	Setter to specify Xpath query.

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

clearViolations, destroy, finishTree, getFileContents, getFilePath, getLine, getLineCodePoints, getLines, getTabWidth, getTokenNames, getViolations, init, leaveToken, log, log, log, setFileContents, setTabWidth, setTokens, visitToken

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 provided by user.

See Also:

• Constant Field Values

query

private String query

Specify Xpath query.

xpathExpression

private net.sf.saxon.sxpath.XPathExpression xpathExpression

Xpath expression.

Constructor Details

MatchXpathCheck

public MatchXpathCheck()

Method Details

setQuery

public void setQuery(String query)

Setter to specify Xpath query.

Parameters:

query - Xpath query.

Throws:

IllegalStateException - if creation of xpath expression fails

Since:

8.39

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

isCommentNodesRequired

public boolean isCommentNodesRequired()

Description copied from class: AbstractCheck

Whether comment nodes are required or not.

Overrides:

isCommentNodesRequired in class AbstractCheck

Returns:

false as a default value.

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

findMatchingNodesByXpathQuery

private List<DetailAST> findMatchingNodesByXpathQuery(DetailAST rootAST)

Find nodes that match query.

Parameters:

rootAST - root node

Returns:

list of matching nodes

Throws:

IllegalStateException - if evaluation of xpath query fails