Package com.puppycrawl.tools.checkstyle.checks.imports

Class AvoidModuleImportCheck

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.imports.AvoidModuleImportCheck

All Implemented Interfaces:

Configurable, Contextualizable

public class AvoidModuleImportCheck
extends AbstractCheck

Checks that there are no module imports.

Rationale: Module import declarations (import module M;) import, on demand, every public top level type exported by a module and by any modules it transitively reads. This is a much broader, less explicit surface than single type or on demand package imports, making it harder to tell where a type comes from, and it increases the risk of ambiguous references between same named types in different exported packages. Disallowing module imports keeps imports explicit and predictable.

Since:

14.1.0

Nested Class Summary

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

AbstractAutomaticBean.OutputStreamOptions

Field Summary

Fields

Modifier and Type	Field	Description
private int	currentModuleImportsCount	Counter for used module imports.
private final Set<String>	excludes	Specify module names for which import module declarations are allowed.
private int	maxAllowedModuleImports	Maximum number of allowed module imports.
static final String	MSG_COUNT	A key is pointing to the warning message text in "messages.properties" file.
static final String	MSG_KEY	A key is pointing to the warning message text in "messages.properties" file.

Constructor Summary

Constructors

Constructor	Description
AvoidModuleImportCheck()	Creates a new AvoidModuleImportCheck instance.

Method Summary

Modifier and Type	Method	Description
void	beginTree(DetailAST rootAST)	Called before the starting to process a tree.
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.
void	setExcludes(String... excludesParam)	Setter to specify modules allowed to import.
void	setMaxAllowedModuleImports(int count)	Setter to control number of module imports allowed.
void	visitToken(DetailAST ast)	Called to process a token.

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

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

MSG_COUNT

public static final String MSG_COUNT

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

See Also:

• Constant Field Values

excludes

private final Set<String> excludes

Specify module names for which import module declarations are allowed.

maxAllowedModuleImports

private int maxAllowedModuleImports

Maximum number of allowed module imports.

currentModuleImportsCount

private int currentModuleImportsCount

Counter for used module imports.

Constructor Details

AvoidModuleImportCheck

public AvoidModuleImportCheck()

Creates a new AvoidModuleImportCheck 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

setExcludes

public void setExcludes(String... excludesParam)

Setter to specify modules allowed to import.

Parameters:

excludesParam - module names

Since:

14.1.0

setMaxAllowedModuleImports

public void setMaxAllowedModuleImports(int count)

Setter to control number of module imports allowed.

Parameters:

count - the number of module imports allowed

Since:

14.1.0

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