com.puppycrawl.tools.checkstyle.checks.coding

Class PackageDeclarationCheck

java.lang.Object

com.puppycrawl.tools.checkstyle.api.AutomaticBean

com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

com.puppycrawl.tools.checkstyle.api.AbstractCheck

com.puppycrawl.tools.checkstyle.checks.coding.PackageDeclarationCheck

All Implemented Interfaces:

Configurable, Contextualizable

public final class PackageDeclarationCheck
extends AbstractCheck

Ensures that a class has a package declaration, and (optionally) whether the package name matches the directory name for the source file.

Rationale: Classes that live in the null package cannot be imported. Many novice developers are not aware of this.

Packages provide logical namespace to classes and should be stored in the form of directory levels to provide physical grouping to your classes. These directories are added to the classpath so that your classes are visible to JVM when it runs the code.

• Property matchDirectoryStructure - Control whether to check for directory and package name match. Type is boolean. Default value is true.

To configure the check:

 <module name="PackageDeclaration"/>
 

Let us consider the class AnnotationLocationCheck which is in the directory /com/puppycrawl/tools/checkstyle/checks/annotations/

 package com.puppycrawl.tools.checkstyle.checks; //Violation
 public class AnnotationLocationCheck extends AbstractCheck {
   //...
 }
 

Example of how the check works when matchDirectoryStructure option is set to false. Let us again consider the AnnotationLocationCheck class located at directory /com/puppycrawl/tools/checkstyle/checks/annotations/ along with the following setup,

 <module name="PackageDeclaration">
 <property name="matchDirectoryStructure" value="false"/>
 </module>
 

 package com.puppycrawl.tools.checkstyle.checks;  //No Violation

 public class AnnotationLocationCheck extends AbstractCheck {
   //...
 }
 

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

• mismatch.package.directory
• missing.package.declaration

Since:

3.2

Nested Class Summary

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

AutomaticBean.OutputStreamOptions

Field Summary

Fields

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

Constructor Summary

Constructors

Constructor and Description
PackageDeclarationCheck()

Method Summary

Modifier and Type	Method and Description
void	beginTree(DetailAST ast) Called before the starting to process a tree.
void	finishTree(DetailAST ast) 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	setMatchDirectoryStructure(boolean matchDirectoryStructure) Setter to control whether to check for directory and package name match.
void	visitToken(DetailAST ast) Called to process a token.

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

clearMessages, destroy, getFileContents, getLine, getLines, getMessages, getTabWidth, getTokenNames, 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.api.AutomaticBean

configure, contextualize, getConfiguration, setupChild

Methods inherited from class java.lang.Object

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

Field Detail

MSG_KEY_MISSING

public static final String MSG_KEY_MISSING

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

See Also:

Constant Field Values

MSG_KEY_MISMATCH

public static final String MSG_KEY_MISMATCH

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

See Also:

Constant Field Values

Constructor Detail

PackageDeclarationCheck

public PackageDeclarationCheck()

Method Detail

setMatchDirectoryStructure

public void setMatchDirectoryStructure(boolean matchDirectoryStructure)

Setter to control whether to check for directory and package name match.

Parameters:

matchDirectoryStructure - the new value.

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

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

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

beginTree

public void beginTree(DetailAST ast)

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:

ast - the root of the tree

finishTree

public void finishTree(DetailAST ast)

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:

ast - 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