AnnotationUseStyleCheck (checkstyle 8.29 API)

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.AnnotationUseStyleCheck

All Implemented Interfaces:

Configurable, Contextualizable
```
public final class AnnotationUseStyleCheck
extends AbstractCheck
```
Checks the style of elements in annotations.

Annotations have three element styles starting with the least verbose.
- ElementStyle.COMPACT_NO_ARRAY
- ElementStyle.COMPACT
- ElementStyle.EXPANDED
To not enforce an element style a ElementStyle.IGNORE type is provided. The desired style can be set through the elementStyle property.

Using the ElementStyle.EXPANDED style is more verbose. The expanded version is sometimes referred to as "named parameters" in other languages.

Using the ElementStyle.COMPACT style is less verbose. This style can only be used when there is an element called 'value' which is either the sole element or all other elements have default values.

Using the ElementStyle.COMPACT_NO_ARRAY style is less verbose. It is similar to the ElementStyle.COMPACT style but single value arrays are flagged. With annotations a single value array does not need to be placed in an array initializer.

The ending parenthesis are optional when using annotations with no elements. To always require ending parenthesis use the ClosingParens.ALWAYS type. To never have ending parenthesis use the ClosingParens.NEVER type. To not enforce a closing parenthesis preference a ClosingParens.IGNORE type is provided. Set this through the closingParens property.

Annotations also allow you to specify arrays of elements in a standard format. As with normal arrays, a trailing comma is optional. To always require a trailing comma use the TrailingArrayComma.ALWAYS type. To never have a trailing comma use the TrailingArrayComma.NEVER type. To not enforce a trailing array comma preference a TrailingArrayComma.IGNORE type is provided. Set this through the trailingArrayComma property.

By default the ElementStyle is set to COMPACT_NO_ARRAY, the TrailingArrayComma is set to NEVER, and the ClosingParens is set to NEVER.

According to the JLS, it is legal to include a trailing comma in arrays used in annotations but Sun's Java 5 & 6 compilers will not compile with this syntax. This may in be a bug in Sun's compilers since eclipse 3.4's built-in compiler does allow this syntax as defined in the JLS. Note: this was tested with compilers included with JDK versions 1.5.0.17 and 1.6.0.11 and the compiler included with eclipse 3.4.1.

See Java Language specification, §9.7.
- Property elementStyle - Define the annotation element styles. Default value is compact_no_array.
- Property closingParens - Define the policy for ending parenthesis. Default value is never.
- Property trailingArrayComma - Define the policy for trailing comma in arrays. Default value is never.
To configure the check:
```
 <module name="AnnotationUseStyle"/>
 
```
To configure the check to enforce an expanded style, with a trailing array comma set to never and always including the closing parenthesis.
```
 <module name="AnnotationUseStyle">
   <property name="elementStyle" value="expanded"/>
   <property name="trailingArrayComma" value="never"/>
   <property name="closingParens" value="always"/>
 </module>
 
```
Since:

5.0

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`AnnotationUseStyleCheck.ClosingParens` Defines the two styles for defining elements in an annotation.
`static class`	`AnnotationUseStyleCheck.ElementStyle` Defines the styles for defining elements in an annotation.
`static class`	`AnnotationUseStyleCheck.TrailingArrayComma` Defines the two styles for defining elements in an annotation.

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

Field Summary

Fields
Modifier and Type	Field and Description
`static java.lang.String`	`MSG_KEY_ANNOTATION_INCORRECT_STYLE` A key is pointing to the warning message text in "messages.properties" file.
`static java.lang.String`	`MSG_KEY_ANNOTATION_PARENS_MISSING` A key is pointing to the warning message text in "messages.properties" file.
`static java.lang.String`	`MSG_KEY_ANNOTATION_PARENS_PRESENT` A key is pointing to the warning message text in "messages.properties" file.
`static java.lang.String`	`MSG_KEY_ANNOTATION_TRAILING_COMMA_MISSING` A key is pointing to the warning message text in "messages.properties" file.
`static java.lang.String`	`MSG_KEY_ANNOTATION_TRAILING_COMMA_PRESENT` A key is pointing to the warning message text in "messages.properties" file.

Constructor Summary

Constructors
Constructor and Description

AnnotationUseStyleCheck()

Constructors
Constructor and Description
`AnnotationUseStyleCheck()`

Method Summary

All Methods Instance Methods Concrete Methods
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`	`setClosingParens(java.lang.String parens)` Setter to define the policy for ending parenthesis.
`void`	`setElementStyle(java.lang.String style)` Setter to define the annotation element styles.
`void`	`setTrailingArrayComma(java.lang.String comma)` Setter to define the policy for trailing comma in arrays.
`void`	`visitToken(DetailAST ast)` Called to process a token.

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck
beginTree, clearMessages, destroy, finishTree, 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_ANNOTATION_INCORRECT_STYLE
```
public static final java.lang.String MSG_KEY_ANNOTATION_INCORRECT_STYLE
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_KEY_ANNOTATION_PARENS_MISSING
```
public static final java.lang.String MSG_KEY_ANNOTATION_PARENS_MISSING
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_KEY_ANNOTATION_PARENS_PRESENT
```
public static final java.lang.String MSG_KEY_ANNOTATION_PARENS_PRESENT
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_KEY_ANNOTATION_TRAILING_COMMA_MISSING
```
public static final java.lang.String MSG_KEY_ANNOTATION_TRAILING_COMMA_MISSING
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_KEY_ANNOTATION_TRAILING_COMMA_PRESENT
```
public static final java.lang.String MSG_KEY_ANNOTATION_TRAILING_COMMA_PRESENT
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - AnnotationUseStyleCheck
```
public AnnotationUseStyleCheck()
```
- Method Detail
  - setElementStyle
```
public void setElementStyle(java.lang.String style)
```
    Setter to define the annotation element styles.
    
    Parameters:
    
    style - string representation
  - setTrailingArrayComma
```
public void setTrailingArrayComma(java.lang.String comma)
```
    Setter to define the policy for trailing comma in arrays.
    
    Parameters:
    
    comma - string representation
  - setClosingParens
```
public void setClosingParens(java.lang.String parens)
```
    Setter to define the policy for ending parenthesis.
    
    Parameters:
    
    parens - string representation
  - 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
  - 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

Class AnnotationUseStyleCheck

Nested Class Summary

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

Field Summary

Constructor Summary

Method Summary

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

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

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

Methods inherited from class java.lang.Object

Field Detail

MSG_KEY_ANNOTATION_INCORRECT_STYLE

MSG_KEY_ANNOTATION_PARENS_MISSING

MSG_KEY_ANNOTATION_PARENS_PRESENT

MSG_KEY_ANNOTATION_TRAILING_COMMA_MISSING

MSG_KEY_ANNOTATION_TRAILING_COMMA_PRESENT

Constructor Detail

AnnotationUseStyleCheck

Method Detail

setElementStyle

setTrailingArrayComma

setClosingParens

getDefaultTokens

getRequiredTokens

getAcceptableTokens

visitToken