com.puppycrawl.tools.checkstyle.checks.annotation

Class AnnotationLocationCheck

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.annotation.AnnotationLocationCheck

All Implemented Interfaces:

Configurable, Contextualizable

public class AnnotationLocationCheck
extends AbstractCheck

Check location of annotation on language elements. By default, Check enforce to locate annotations immediately after documentation block and before target element, annotation should be located on separate line from target element.

Attention: Annotations among modifiers are ignored (looks like false-negative) as there might be a problem with annotations for return types.

public @Nullable Long getStartTimeOrNull() { ... }

.

Such annotations are better to keep close to type. Due to limitations, Checkstyle can not examine the target of an annotation.

Example:

 @Override
 @Nullable
 public String getNameIfPresent() { ... }
 

The check has the following options:

• allowSamelineMultipleAnnotations - to allow annotation to be located on the same line as the target element. Default value is false.
• allowSamelineSingleParameterlessAnnotation - to allow single parameterless annotation to be located on the same line as the target element. Default value is false.
• allowSamelineParameterizedAnnotation - to allow parameterized annotation to be located on the same line as the target element. Default value is false.

Example to allow single parameterless annotation on the same line:

 @Override public int hashCode() { ... }
 

Use the following configuration:

 <module name="AnnotationLocation">
    <property name="allowSamelineMultipleAnnotations" value="false"/>
    <property name="allowSamelineSingleParameterlessAnnotation"
    value="true"/>
    <property name="allowSamelineParameterizedAnnotation" value="false"
    />
 </module>
 

Example to allow multiple parameterized annotations on the same line:

 @SuppressWarnings("deprecation") @Mock DataLoader loader;
 

Use the following configuration:

 <module name="AnnotationLocation">
    <property name="allowSamelineMultipleAnnotations" value="true"/>
    <property name="allowSamelineSingleParameterlessAnnotation"
    value="true"/>
    <property name="allowSamelineParameterizedAnnotation" value="true"
    />
 </module>
 

Example to allow multiple parameterless annotations on the same line:

 @Partial @Mock DataLoader loader;
 

Use the following configuration:

 <module name="AnnotationLocation">
    <property name="allowSamelineMultipleAnnotations" value="true"/>
    <property name="allowSamelineSingleParameterlessAnnotation"
    value="true"/>
    <property name="allowSamelineParameterizedAnnotation" value="false"
    />
 </module>
 

The following example demonstrates how the check validates annotation of method parameters, catch parameters, foreach, for-loop variable definitions.

Configuration:

 <module name="AnnotationLocation">
    <property name="allowSamelineMultipleAnnotations" value="false"/>
    <property name="allowSamelineSingleParameterlessAnnotation"
    value="false"/>
    <property name="allowSamelineParameterizedAnnotation" value="false"
    />
    <property name="tokens" value="VARIABLE_DEF, PARAMETER_DEF"/>
 </module>
 

Code example ... public void test(@MyAnnotation String s) { // OK ... for (@MyAnnotation char c : s.toCharArray()) { ... } // OK ... try { ... } catch (@MyAnnotation Exception ex) { ... } // OK ... for (@MyAnnotation int i = 0; i < 10; i++) { ... } // OK ... MathOperation c = (@MyAnnotation int a, @MyAnnotation int b) -> a + b; // OK ... }

Author:

maxvetrenko

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_ANNOTATION_LOCATION A key is pointing to the warning message text in "messages.properties" file.
static String	MSG_KEY_ANNOTATION_LOCATION_ALONE A key is pointing to the warning message text in "messages.properties" file.

Constructor Summary

Constructors

Constructor and Description
AnnotationLocationCheck()

Method Summary

Modifier and Type	Method and Description
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	setAllowSamelineMultipleAnnotations(boolean allow) Sets if allow annotation to be located on the same line as target element.
void	setAllowSamelineParameterizedAnnotation(boolean allow) Sets if allow parameterized annotation to be located on the same line as target element.
void	setAllowSamelineSingleParameterlessAnnotation(boolean allow) Sets if allow same line single parameterless annotation.
void	visitToken(DetailAST ast) Called to process a token.

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

beginTree, clearMessages, destroy, finishTree, getClassLoader, getFileContents, getLine, getLines, getMessages, getTabWidth, getTokenNames, init, isCommentNodesRequired, leaveToken, log, log, log, setClassLoader, 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_ANNOTATION_LOCATION_ALONE

public static final String MSG_KEY_ANNOTATION_LOCATION_ALONE

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

See Also:

Constant Field Values

MSG_KEY_ANNOTATION_LOCATION

public static final String MSG_KEY_ANNOTATION_LOCATION

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

See Also:

Constant Field Values

Constructor Detail

AnnotationLocationCheck

public AnnotationLocationCheck()

Method Detail

setAllowSamelineSingleParameterlessAnnotation

public final void setAllowSamelineSingleParameterlessAnnotation(boolean allow)

Sets if allow same line single parameterless annotation.

Parameters:

allow - User's value of allowSamelineSingleParameterlessAnnotation.

setAllowSamelineParameterizedAnnotation

public final void setAllowSamelineParameterizedAnnotation(boolean allow)

Sets if allow parameterized annotation to be located on the same line as target element.

Parameters:

allow - User's value of allowSamelineParameterizedAnnotation.

setAllowSamelineMultipleAnnotations

public final void setAllowSamelineMultipleAnnotations(boolean allow)

Sets if allow annotation to be located on the same line as target element.

Parameters:

allow - User's value of allowSamelineMultipleAnnotations.

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

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