Class QualifierAnnotationAutowireCandidateResolver

Constructor Detail

• QualifierAnnotationAutowireCandidateResolver

  public QualifierAnnotationAutowireCandidateResolver()

  Create a new QualifierAnnotationAutowireCandidateResolver for Spring's standard Qualifier annotation.

  Also supports JSR-330's Qualifier annotation, if available.

• QualifierAnnotationAutowireCandidateResolver

  public QualifierAnnotationAutowireCandidateResolver​(Class<? extends Annotation> qualifierType)

  Create a new QualifierAnnotationAutowireCandidateResolver for the given qualifier annotation type.

  Parameters:

  qualifierType - the qualifier annotation to look for

• QualifierAnnotationAutowireCandidateResolver

  public QualifierAnnotationAutowireCandidateResolver​(Set<Class<? extends Annotation>> qualifierTypes)

  Create a new QualifierAnnotationAutowireCandidateResolver for the given qualifier annotation types.

  Parameters:

  qualifierTypes - the qualifier annotations to look for

Method Detail

• addQualifierType

  public void addQualifierType​(Class<? extends Annotation> qualifierType)

  Register the given type to be used as a qualifier when autowiring.

  This identifies qualifier annotations for direct use (on fields, method parameters and constructor parameters) as well as meta annotations that in turn identify actual qualifier annotations.

  This implementation only supports annotations as qualifier types. The default is Spring's Qualifier annotation which serves as a qualifier for direct use and also as a meta annotation.

  Parameters:

  qualifierType - the annotation type to register

• setValueAnnotationType

  public void setValueAnnotationType​(Class<? extends Annotation> valueAnnotationType)

  Set the 'value' annotation type, to be used on fields, method parameters and constructor parameters.

  The default value annotation type is the Spring-provided Value annotation.

  This setter property exists so that developers can provide their own (non-Spring-specific) annotation type to indicate a default value expression for a specific argument.

• isAutowireCandidate

  public boolean isAutowireCandidate​(BeanDefinitionHolder bdHolder,
                                     DependencyDescriptor descriptor)

  Determine whether the provided bean definition is an autowire candidate.

  To be considered a candidate the bean's autowire-candidate attribute must not have been set to 'false'. Also, if an annotation on the field or parameter to be autowired is recognized by this bean factory as a qualifier, the bean must 'match' against the annotation as well as any attributes it may contain. The bean definition must contain the same qualifier or match by meta attributes. A "value" attribute will fallback to match against the bean name or an alias if a qualifier or attribute does not match.

  Specified by:

  isAutowireCandidate in interface AutowireCandidateResolver

  Overrides:

  isAutowireCandidate in class GenericTypeAwareAutowireCandidateResolver

  Parameters:

  bdHolder - the bean definition including bean name and aliases

  descriptor - the descriptor for the target method parameter or field

  Returns:

  whether the bean definition qualifies as autowire candidate

  See Also:

  Qualifier

• checkQualifiers

  protected boolean checkQualifiers​(BeanDefinitionHolder bdHolder,
                                    Annotation[] annotationsToSearch)

  Match the given qualifier annotations against the candidate bean definition.

• isQualifier

  protected boolean isQualifier​(Class<? extends Annotation> annotationType)

  Checks whether the given annotation type is a recognized qualifier type.

• checkQualifier

  protected boolean checkQualifier​(BeanDefinitionHolder bdHolder,
                                   Annotation annotation,
                                   TypeConverter typeConverter)

  Match the given qualifier annotation against the candidate bean definition.

• getQualifiedElementAnnotation

  @Nullable
  protected Annotation getQualifiedElementAnnotation​(RootBeanDefinition bd,
                                                     Class<? extends Annotation> type)

• getFactoryMethodAnnotation

  @Nullable
  protected Annotation getFactoryMethodAnnotation​(RootBeanDefinition bd,
                                                  Class<? extends Annotation> type)

• isRequired

  public boolean isRequired​(DependencyDescriptor descriptor)

  Determine whether the given dependency declares an autowired annotation, checking its required flag.

  Specified by:

  isRequired in interface AutowireCandidateResolver

  Overrides:

  isRequired in class SimpleAutowireCandidateResolver

  Parameters:

  descriptor - the descriptor for the target method parameter or field

  Returns:

  whether the descriptor is marked as required or possibly indicating non-required status some other way (e.g. through a parameter annotation)

  See Also:

  Autowired.required()

• hasQualifier

  public boolean hasQualifier​(DependencyDescriptor descriptor)

  Determine whether the given dependency declares a qualifier annotation.

  Specified by:

  hasQualifier in interface AutowireCandidateResolver

  Overrides:

  hasQualifier in class SimpleAutowireCandidateResolver

  Parameters:

  descriptor - the descriptor for the target method parameter or field

  Returns:

  whether the descriptor declares a qualifier, narrowing the candidate status beyond the type match

  See Also:

  isQualifier(Class), Qualifier

• getSuggestedValue

  @Nullable
  public Object getSuggestedValue​(DependencyDescriptor descriptor)

  Determine whether the given dependency declares a value annotation.

  Specified by:

  getSuggestedValue in interface AutowireCandidateResolver

  Overrides:

  getSuggestedValue in class SimpleAutowireCandidateResolver

  Parameters:

  descriptor - the descriptor for the target method parameter or field

  Returns:

  the value suggested (typically an expression String), or null if none found

  See Also:

  Value

• findValue

  @Nullable
  protected Object findValue​(Annotation[] annotationsToSearch)

  Determine a suggested value from any of the given candidate annotations.

• extractValue

  protected Object extractValue​(AnnotationAttributes attr)

  Extract the value attribute from the given annotation.

  Since:

  4.3