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

Class ModuleImportOrderCheck

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.ModuleImportOrderCheck

All Implemented Interfaces:

Configurable, Contextualizable

public class ModuleImportOrderCheck
extends AbstractCheck

Checks the ordering and placement of module import declarations. Features are:

• position of module imports: ensures that module imports are placed above or below all type and static imports (see ModuleImportOrderOption)
• sorts module imports: ensures that module imports are sorted lexicographically by qualified module name, in ASCII sort order
• adds a separation between module imports and other imports: ensures that the module import block is separated from type and static imports by, at least, one blank line or comment

This check only validates module imports. It observes type and static imports to locate the boundary of the module import block, but does not validate their order. Use ImportOrder alongside this check for those.

Since:

14.1.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static final record	ModuleImportOrderCheck.ImportEntry	Contains import attributes as import full path, module flag and import AST.

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

AbstractAutomaticBean.OutputStreamOptions

Field Summary

Fields

Modifier and Type	Field	Description
private final List<ModuleImportOrderCheck.ImportEntry>	imports	Imports of the current file in order of appearance.
static final String	MSG_ORDERING_LEX	A key pointing to the warning message text in "messages.properties" file.
static final String	MSG_POSITION	A key pointing to the warning message text in "messages.properties" file.
static final String	MSG_SEPARATION	A key pointing to the warning message text in "messages.properties" file.
private ModuleImportOrderOption	option	Specify policy on the position of module imports relative to type and static imports.
private boolean	separated	Control whether the module import block should be separated from type and static imports by, at least, one blank line or comment.

Constructor Summary

Constructors

Constructor	Description
ModuleImportOrderCheck()	Creates a new ModuleImportOrderCheck instance.

Method Summary

Modifier and Type	Method	Description
void	beginTree(DetailAST rootAST)	Called before the starting to process a tree.
private void	checkLexicographicalOrder()	Checks that module imports are sorted lexicographically.
private boolean	checkPosition()	Checks that module imports are placed above or below all type and static imports, according to the configured option.
private void	checkSeparation()	Checks that the module import block is separated from the adjacent type and static import block by, at least, one blank line or comment.
void	finishTree(DetailAST rootAST)	Called after finished processing 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	setOption(String optionStr)	Setter to specify policy on the position of module imports relative to type and static imports.
void	setSeparated(boolean separated)	Setter to control whether the module import block should be separated from type and static imports by, at least, one blank line or comment.
void	visitToken(DetailAST ast)	Called to process a token.

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

clearViolations, destroy, 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_POSITION

public static final String MSG_POSITION

A key pointing to the warning message text in "messages.properties" file. Emitted when a module import is not placed above or below all type and static imports, as required by the configured option.

See Also:

• Constant Field Values

MSG_SEPARATION

public static final String MSG_SEPARATION

A key pointing to the warning message text in "messages.properties" file. Emitted when the module import block is not separated from type and static imports by a blank line.

See Also:

• Constant Field Values

MSG_ORDERING_LEX

public static final String MSG_ORDERING_LEX

A key pointing to the warning message text in "messages.properties" file. Emitted when module imports are not sorted lexicographically by qualified module name.

See Also:

• Constant Field Values

imports

private final List<ModuleImportOrderCheck.ImportEntry> imports

Imports of the current file in order of appearance.

option

private ModuleImportOrderOption option

Specify policy on the position of module imports relative to type and static imports.

separated

private boolean separated

Control whether the module import block should be separated from type and static imports by, at least, one blank line or comment.

Constructor Details

ModuleImportOrderCheck

public ModuleImportOrderCheck()

Creates a new ModuleImportOrderCheck instance.

Method Details

setOption

public void setOption(String optionStr)

Setter to specify policy on the position of module imports relative to type and static imports.

Parameters:

optionStr - string to decode option from

Throws:

IllegalArgumentException - if unable to decode

Since:

14.1.0

setSeparated

public void setSeparated(boolean separated)

Setter to control whether the module import block should be separated from type and static imports by, at least, one blank line or comment.

Parameters:

separated - whether the module import block should be separated.

Since:

14.1.0

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

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

finishTree

public void finishTree(DetailAST rootAST)

Description copied from class: AbstractCheck

Called after finished processing a tree. Ideal place to report on information collected whilst processing a tree.

Overrides:

finishTree in class AbstractCheck

Parameters:

rootAST - the root of the tree

checkLexicographicalOrder

private void checkLexicographicalOrder()

Checks that module imports are sorted lexicographically. Each module import is compared with the previous module import, regardless of any type or static imports between them.

checkPosition

private boolean checkPosition()

Checks that module imports are placed above or below all type and static imports, according to the configured option.

Returns:

true if any position violation was logged.

checkSeparation

private void checkSeparation()

Checks that the module import block is separated from the adjacent type and static import block by, at least, one blank line or comment. This method is only invoked when module imports are correctly positioned, so all module imports form a single block above or below all other imports.