Class DependencyDescriptor
- All Implemented Interfaces:
Serializable
- Since:
- 2.5
- Author:
- Juergen Hoeller
- See Also:
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Field Summary
Fields inherited from class org.springframework.beans.factory.InjectionPoint
field, methodParameter
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Constructor Summary
ConstructorDescriptionDependencyDescriptor
(Field field, boolean required) Create a new descriptor for a field.DependencyDescriptor
(Field field, boolean required, boolean eager) Create a new descriptor for a field.DependencyDescriptor
(DependencyDescriptor original) Copy constructor.DependencyDescriptor
(MethodParameter methodParameter, boolean required) Create a new descriptor for a method or constructor parameter.DependencyDescriptor
(MethodParameter methodParameter, boolean required, boolean eager) Create a new descriptor for a method or constructor parameter. -
Method Summary
Modifier and TypeMethodDescriptionboolean
boolean
Return whether a fallback match is allowed.Return a variant of this descriptor that is intended for a fallback match.Determine the name of the wrapped parameter/field.Class<?>
Determine the declared (non-generic) type of the wrapped parameter/field.Build aResolvableType
object for the wrapped parameter/field.Build aTypeDescriptor
object for the wrapped parameter/field.int
hashCode()
void
Increase this descriptor's nesting level.void
initParameterNameDiscovery
(ParameterNameDiscoverer parameterNameDiscoverer) Initialize parameter name discovery for the underlying method parameter, if any.boolean
isEager()
Return whether this dependency is 'eager' in the sense of eagerly resolving potential target beans for type matching.boolean
Return whether this dependency is required.resolveCandidate
(String beanName, Class<?> requiredType, BeanFactory beanFactory) Resolve the specified bean name, as a candidate result of the matching algorithm for this dependency, to a bean instance from the given factory.resolveNotUnique
(ResolvableType type, Map<String, Object> matchingBeans) Resolve the specified not-unique scenario: by default, throwing aNoUniqueBeanDefinitionException
.resolveShortcut
(BeanFactory beanFactory) Resolve a shortcut for this dependency against the given factory, for example taking some pre-resolved information into account.void
setContainingClass
(Class<?> containingClass) Optionally set the concrete class that contains this dependency.boolean
Determine whether this dependency supports lazy resolution, e.g.Methods inherited from class org.springframework.beans.factory.InjectionPoint
getAnnotatedElement, getAnnotation, getAnnotations, getDeclaredType, getField, getMember, getMethodParameter, obtainMethodParameter, toString
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Constructor Details
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DependencyDescriptor
Create a new descriptor for a method or constructor parameter. Considers the dependency as 'eager'.- Parameters:
methodParameter
- the MethodParameter to wraprequired
- whether the dependency is required
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DependencyDescriptor
Create a new descriptor for a method or constructor parameter.- Parameters:
methodParameter
- the MethodParameter to wraprequired
- whether the dependency is requiredeager
- whether this dependency is 'eager' in the sense of eagerly resolving potential target beans for type matching
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DependencyDescriptor
Create a new descriptor for a field. Considers the dependency as 'eager'.- Parameters:
field
- the field to wraprequired
- whether the dependency is required
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DependencyDescriptor
Create a new descriptor for a field.- Parameters:
field
- the field to wraprequired
- whether the dependency is requiredeager
- whether this dependency is 'eager' in the sense of eagerly resolving potential target beans for type matching
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DependencyDescriptor
Copy constructor.- Parameters:
original
- the original descriptor to create a copy from
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Method Details
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isRequired
public boolean isRequired()Return whether this dependency is required.Optional semantics are derived from Java 8's
Optional
, any variant of a parameter-levelNullable
annotation (such as from JSR-305 or the FindBugs set of annotations), or a language-level nullable type declaration in Kotlin. -
isEager
public boolean isEager()Return whether this dependency is 'eager' in the sense of eagerly resolving potential target beans for type matching. -
resolveNotUnique
@Nullable public Object resolveNotUnique(ResolvableType type, Map<String, Object> matchingBeans) throws BeansExceptionResolve the specified not-unique scenario: by default, throwing aNoUniqueBeanDefinitionException
.Subclasses may override this to select one of the instances or to opt out with no result at all through returning
null
.- Parameters:
type
- the requested bean typematchingBeans
- a map of bean names and corresponding bean instances which have been pre-selected for the given type (qualifiers etc already applied)- Returns:
- a bean instance to proceed with, or
null
for none - Throws:
BeansException
- in case of the not-unique scenario being fatal- Since:
- 5.1
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resolveShortcut
Resolve a shortcut for this dependency against the given factory, for example taking some pre-resolved information into account.The resolution algorithm will first attempt to resolve a shortcut through this method before going into the regular type matching algorithm across all beans. Subclasses may override this method to improve resolution performance based on pre-cached information while still receiving
InjectionPoint
exposure etc.- Parameters:
beanFactory
- the associated factory- Returns:
- the shortcut result if any, or
null
if none - Throws:
BeansException
- if the shortcut could not be obtained- Since:
- 4.3.1
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resolveCandidate
public Object resolveCandidate(String beanName, Class<?> requiredType, BeanFactory beanFactory) throws BeansException Resolve the specified bean name, as a candidate result of the matching algorithm for this dependency, to a bean instance from the given factory.The default implementation calls
BeanFactory.getBean(String)
. Subclasses may provide additional arguments or other customizations.- Parameters:
beanName
- the bean name, as a candidate result for this dependencyrequiredType
- the expected type of the bean (as an assertion)beanFactory
- the associated factory- Returns:
- the bean instance (never
null
) - Throws:
BeansException
- if the bean could not be obtained- Since:
- 4.3.2
- See Also:
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increaseNestingLevel
public void increaseNestingLevel()Increase this descriptor's nesting level. -
setContainingClass
Optionally set the concrete class that contains this dependency. This may differ from the class that declares the parameter/field in that it may be a subclass thereof, potentially substituting type variables.- Since:
- 4.0
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getResolvableType
Build aResolvableType
object for the wrapped parameter/field.- Since:
- 4.0
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getTypeDescriptor
Build aTypeDescriptor
object for the wrapped parameter/field.- Since:
- 5.1.4
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fallbackMatchAllowed
public boolean fallbackMatchAllowed()Return whether a fallback match is allowed.This is
false
by default but may be overridden to returntrue
in order to suggest to anAutowireCandidateResolver
that a fallback match is acceptable as well.- Since:
- 4.0
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forFallbackMatch
Return a variant of this descriptor that is intended for a fallback match.- Since:
- 4.0
- See Also:
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initParameterNameDiscovery
Initialize parameter name discovery for the underlying method parameter, if any.This method does not actually try to retrieve the parameter name at this point; it just allows discovery to happen when the application calls
getDependencyName()
(if ever). -
getDependencyName
Determine the name of the wrapped parameter/field.- Returns:
- the declared name (may be
null
if unresolvable)
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getDependencyType
Determine the declared (non-generic) type of the wrapped parameter/field.- Returns:
- the declared type (never
null
)
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supportsLazyResolution
public boolean supportsLazyResolution()Determine whether this dependency supports lazy resolution, e.g. through extra proxying. The default istrue
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equals
- Overrides:
equals
in classInjectionPoint
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hashCode
public int hashCode()- Overrides:
hashCode
in classInjectionPoint
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