com.puppycrawl.tools.checkstyle

Class TreeWalker

java.lang.Object

com.puppycrawl.tools.checkstyle.api.AutomaticBean

com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

com.puppycrawl.tools.checkstyle.api.AbstractFileSetCheck

com.puppycrawl.tools.checkstyle.TreeWalker

All Implemented Interfaces:

Configurable, Contextualizable, ExternalResourceHolder, FileSetCheck

public final class TreeWalker
extends AbstractFileSetCheck
implements ExternalResourceHolder

Responsible for walking an abstract syntax tree and notifying interested checks at each each node.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	TreeWalker.AstState State of AST.

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

AutomaticBean.OutputStreamOptions

Field Summary

Fields

Modifier and Type	Field and Description
private Context	childContext Context of child components.
private java.util.Set<AbstractCheck>	commentChecks Registered comment checks.
private java.util.Set<TreeWalkerFilter>	filters The ast filters.
private ModuleFactory	moduleFactory A factory for creating submodules (i.e.
private java.util.Set<AbstractCheck>	ordinaryChecks Registered ordinary checks, that don't use comment nodes.
private java.util.Map<java.lang.Integer,java.util.Set<AbstractCheck>>	tokenToCommentChecks Maps from token name to comment checks.
private java.util.Map<java.lang.Integer,java.util.Set<AbstractCheck>>	tokenToOrdinaryChecks Maps from token name to ordinary checks.
private java.util.SortedSet<Violation>	violations The sorted set of violations.

Constructor Summary

Constructors

Constructor and Description
TreeWalker() Creates a new TreeWalker instance.

Method Summary

Modifier and Type	Method and Description
private static java.util.SortedSet<AbstractCheck>	createNewCheckSortedSet() Creates a new SortedSet with a deterministic order based on the Check's name before the default ordering.
void	destroy() Cleans up the object.
void	finishLocalSetup() Provides a hook to finish the part of this component's setup that was not handled by the bean introspection.
java.util.Set<java.lang.String>	getExternalResourceLocations() Returns a set of external configuration resource locations which are used by the module.
private java.util.SortedSet<Violation>	getFilteredViolations(java.lang.String fileName, FileContents fileContents, DetailAST rootAST) Returns filtered set of Violation.
private java.util.Collection<AbstractCheck>	getListOfChecks(DetailAST ast, TreeWalker.AstState astState) Method returns list of checks.
private void	notifyBegin(DetailAST rootAST, FileContents contents, TreeWalker.AstState astState) Notify checks that we are about to begin walking a tree.
private void	notifyEnd(DetailAST rootAST, TreeWalker.AstState astState) Notify checks that we have finished walking a tree.
private void	notifyLeave(DetailAST ast, TreeWalker.AstState astState) Notify checks that leaving a node.
private void	notifyVisit(DetailAST ast, TreeWalker.AstState astState) Notify checks that visiting a node.
protected void	processFiltered(java.io.File file, FileText fileText) Called to process a file that matches the specified file extensions.
private void	processIter(DetailAST root, TreeWalker.AstState astState) Processes a node calling interested checks at each node.
private void	registerCheck(AbstractCheck check) Register a check for a given configuration.
private void	registerCheck(int tokenId, AbstractCheck check) Register a check for a specified token id.
void	setModuleFactory(ModuleFactory moduleFactory) Sets the module factory for creating child modules (Checks).
void	setupChild(Configuration childConf) Called by configure() for every child of this component's Configuration.
private void	walk(DetailAST ast, FileContents contents, TreeWalker.AstState astState) Initiates the walk of an AST.

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

addViolations, beginProcessing, finishProcessing, fireErrors, getFileContents, getFileExtensions, getMessageDispatcher, getTabWidth, getViolations, init, log, log, process, setFileContents, setFileExtensions, setMessageDispatcher, setTabWidth

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

getCustomMessages, getId, getMessageBundle, getSeverity, getSeverityLevel, setId, setSeverity

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

configure, contextualize, getConfiguration

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.puppycrawl.tools.checkstyle.api.Configurable

configure

Methods inherited from interface com.puppycrawl.tools.checkstyle.api.Contextualizable

contextualize

Field Detail

tokenToOrdinaryChecks

private final java.util.Map<java.lang.Integer,java.util.Set<AbstractCheck>> tokenToOrdinaryChecks

Maps from token name to ordinary checks.

tokenToCommentChecks

private final java.util.Map<java.lang.Integer,java.util.Set<AbstractCheck>> tokenToCommentChecks

Maps from token name to comment checks.

ordinaryChecks

private final java.util.Set<AbstractCheck> ordinaryChecks

Registered ordinary checks, that don't use comment nodes.

commentChecks

private final java.util.Set<AbstractCheck> commentChecks

Registered comment checks.

filters

private final java.util.Set<TreeWalkerFilter> filters

The ast filters.

violations

private final java.util.SortedSet<Violation> violations

The sorted set of violations.

childContext

private Context childContext

Context of child components.

moduleFactory

private ModuleFactory moduleFactory

A factory for creating submodules (i.e. the Checks)

Constructor Detail

TreeWalker

public TreeWalker()

Creates a new TreeWalker instance.

Method Detail

setModuleFactory

public void setModuleFactory(ModuleFactory moduleFactory)

Sets the module factory for creating child modules (Checks).

Parameters:

moduleFactory - the factory

finishLocalSetup

public void finishLocalSetup()

Description copied from class: AutomaticBean

Provides a hook to finish the part of this component's setup that was not handled by the bean introspection.

The default implementation does nothing.

Overrides:

finishLocalSetup in class AbstractViolationReporter

setupChild

public void setupChild(Configuration childConf)
                throws CheckstyleException

Called by configure() for every child of this component's Configuration.

The default implementation throws CheckstyleException if childConf is null because it doesn't support children. It must be overridden to validate and support children that are wanted.

Creates child module.

Overrides:

setupChild in class AutomaticBean

Parameters:

childConf - a child of this component's Configuration

Throws:

CheckstyleException - if there is a configuration error.

See Also:

Configuration.getChildren()

processFiltered

protected void processFiltered(java.io.File file,
                               FileText fileText)
                        throws CheckstyleException

Description copied from class: AbstractFileSetCheck

Called to process a file that matches the specified file extensions.

Specified by:

processFiltered in class AbstractFileSetCheck

Parameters:

file - the file to be processed

fileText - the contents of the file.

Throws:

CheckstyleException - if error condition within Checkstyle occurs.

getFilteredViolations

private java.util.SortedSet<Violation> getFilteredViolations(java.lang.String fileName,
                                                             FileContents fileContents,
                                                             DetailAST rootAST)

Returns filtered set of Violation.

Parameters:

fileName - path to the file

fileContents - the contents of the file

rootAST - root AST element DetailAST of the file

Returns:

filtered set of violations

registerCheck

private void registerCheck(AbstractCheck check)
                    throws CheckstyleException

Register a check for a given configuration.

Parameters:

check - the check to register

Throws:

CheckstyleException - if an error occurs

registerCheck

private void registerCheck(int tokenId,
                           AbstractCheck check)
                    throws CheckstyleException

Register a check for a specified token id.

Parameters:

tokenId - the id of the token

check - the check to register

Throws:

CheckstyleException - if Check is misconfigured

walk

private void walk(DetailAST ast,
                  FileContents contents,
                  TreeWalker.AstState astState)

Initiates the walk of an AST.

Parameters:

ast - the root AST

contents - the contents of the file the AST was generated from.

astState - state of AST.

notifyBegin

private void notifyBegin(DetailAST rootAST,
                         FileContents contents,
                         TreeWalker.AstState astState)

Notify checks that we are about to begin walking a tree.

Parameters:

rootAST - the root of the tree.

contents - the contents of the file the AST was generated from.

astState - state of AST.

notifyEnd

private void notifyEnd(DetailAST rootAST,
                       TreeWalker.AstState astState)

Notify checks that we have finished walking a tree.

Parameters:

rootAST - the root of the tree.

astState - state of AST.

notifyVisit

private void notifyVisit(DetailAST ast,
                         TreeWalker.AstState astState)

Notify checks that visiting a node.

Parameters:

ast - the node to notify for.

astState - state of AST.

notifyLeave

private void notifyLeave(DetailAST ast,
                         TreeWalker.AstState astState)

Notify checks that leaving a node.

Parameters:

ast - the node to notify for

astState - state of AST.

getListOfChecks

private java.util.Collection<AbstractCheck> getListOfChecks(DetailAST ast,
                                                            TreeWalker.AstState astState)

Method returns list of checks.

Parameters:

ast - the node to notify for

astState - state of AST.

Returns:

list of visitors

destroy

public void destroy()

Description copied from interface: FileSetCheck

Cleans up the object.

Specified by:

destroy in interface FileSetCheck

Overrides:

destroy in class AbstractFileSetCheck

getExternalResourceLocations

public java.util.Set<java.lang.String> getExternalResourceLocations()

Description copied from interface: ExternalResourceHolder

Returns a set of external configuration resource locations which are used by the module. ATTENTION! If 'getExternalResourceLocations()' return null, there will be NullPointerException in Checker. Such behaviour will signal that your module (check or filter) is designed incorrectly. It make sense to return an empty set from 'getExternalResourceLocations()' only for composite modules like TreeWalker.

Specified by:

getExternalResourceLocations in interface ExternalResourceHolder

Returns:

a set of external configuration resource locations which are used by the module.

processIter

private void processIter(DetailAST root,
                         TreeWalker.AstState astState)

Processes a node calling interested checks at each node. Uses iterative algorithm.

Parameters:

root - the root of tree for process

astState - state of AST.

createNewCheckSortedSet

private static java.util.SortedSet<AbstractCheck> createNewCheckSortedSet()

Creates a new SortedSet with a deterministic order based on the Check's name before the default ordering.

Returns:

The new SortedSet.