AnnotationIntrospector.java
package com.fasterxml.jackson.databind;
import java.lang.annotation.Annotation;
import java.util.*;
import com.fasterxml.jackson.annotation.*;
import com.fasterxml.jackson.core.Version;
import com.fasterxml.jackson.core.Versioned;
import com.fasterxml.jackson.databind.annotation.JsonPOJOBuilder;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import com.fasterxml.jackson.databind.cfg.MapperConfig;
import com.fasterxml.jackson.databind.deser.ValueInstantiator;
import com.fasterxml.jackson.databind.introspect.*;
import com.fasterxml.jackson.databind.jsontype.NamedType;
import com.fasterxml.jackson.databind.jsontype.TypeResolverBuilder;
import com.fasterxml.jackson.databind.ser.BeanPropertyWriter;
import com.fasterxml.jackson.databind.util.Converter;
import com.fasterxml.jackson.databind.util.NameTransformer;
/**
* Abstract class that defines API used for introspecting annotation-based
* configuration for serialization and deserialization. Separated
* so that different sets of annotations can be supported, and support
* plugged-in dynamically.
*<p>
* Although default implementations are based on using annotations as the only
* (or at least main) information source, custom implementations are not limited
* in such a way, and in fact there is no expectation they should be. So the name
* is bit of misnomer; this is a general configuration introspection facility.
*<p>
* NOTE: due to rapid addition of new methods (and changes to existing methods),
* it is <b>strongly</b> recommended that custom implementations should not directly
* extend this class, but rather extend {@link NopAnnotationIntrospector}.
* This way added methods will not break backwards compatibility of custom annotation
* introspectors.
*/
@SuppressWarnings("serial")
public abstract class AnnotationIntrospector
implements Versioned, java.io.Serializable
{
/*
/**********************************************************************
/* Helper types
/**********************************************************************
*/
/**
* Value type used with managed and back references; contains type and
* logic name, used to link related references
*/
public static class ReferenceProperty
{
public enum Type {
/**
* Reference property that Jackson manages and that is serialized normally (by serializing
* reference object), but is used for resolving back references during
* deserialization.
* Usually this can be defined by using
* {@link com.fasterxml.jackson.annotation.JsonManagedReference}
*/
MANAGED_REFERENCE,
/**
* Reference property that Jackson manages by suppressing it during serialization,
* and reconstructing during deserialization.
* Usually this can be defined by using
* {@link com.fasterxml.jackson.annotation.JsonBackReference}
*/
BACK_REFERENCE
;
}
private final Type _type;
private final String _name;
public ReferenceProperty(Type t, String n) {
_type = t;
_name = n;
}
public static ReferenceProperty managed(String name) { return new ReferenceProperty(Type.MANAGED_REFERENCE, name); }
public static ReferenceProperty back(String name) { return new ReferenceProperty(Type.BACK_REFERENCE, name); }
public Type getType() { return _type; }
public String getName() { return _name; }
public boolean isManagedReference() { return _type == Type.MANAGED_REFERENCE; }
public boolean isBackReference() { return _type == Type.BACK_REFERENCE; }
}
/**
* Add-on extension used for XML-specific configuration, needed to decouple
* format module functionality from pluggable introspection functionality
* (especially JAXB-annotation related one).
*
* @since 2.13
*/
public interface XmlExtensions
{
/**
* Method that can be called to figure out generic namespace
* property for an annotated object.
*
* @param config Configuration settings in effect
* @param ann Annotated entity to introspect
*
* @return Null if annotated thing does not define any
* namespace information; non-null namespace (which may
* be empty String) otherwise.
*/
public String findNamespace(MapperConfig<?> config, Annotated ann);
/**
* Method used to check whether given annotated element
* (field, method, constructor parameter) has indicator that suggests
* it be output as an XML attribute or not (if not, then as element)
*
* @param config Configuration settings in effect
* @param ann Annotated entity to introspect
*
* @return Null if no indicator found; {@code True} or {@code False} otherwise
*/
public Boolean isOutputAsAttribute(MapperConfig<?> config, Annotated ann);
/**
* Method used to check whether given annotated element
* (field, method, constructor parameter) has indicator that suggests
* it should be serialized as text, without element wrapper.
*
* @param config Configuration settings in effect
* @param ann Annotated entity to introspect
*
* @return Null if no indicator found; {@code True} or {@code False} otherwise
*/
public Boolean isOutputAsText(MapperConfig<?> config, Annotated ann);
/**
* Method used to check whether given annotated element
* (field, method, constructor parameter) has indicator that suggests
* it should be wrapped in a CDATA tag.
*
* @param config Configuration settings in effect
* @param ann Annotated entity to introspect
*
* @return Null if no indicator found; {@code True} or {@code False} otherwise
*/
public Boolean isOutputAsCData(MapperConfig<?> config, Annotated ann);
}
/*
/**********************************************************************
/* Factory methods
/**********************************************************************
*/
/**
* Factory method for accessing "no operation" implementation
* of introspector: instance that will never find any annotation-based
* configuration.
*
* @return "no operation" instance
*/
public static AnnotationIntrospector nopInstance() {
return NopAnnotationIntrospector.instance;
}
public static AnnotationIntrospector pair(AnnotationIntrospector a1, AnnotationIntrospector a2) {
return new AnnotationIntrospectorPair(a1, a2);
}
/*
/**********************************************************
/* Access to possibly chained introspectors
/**********************************************************
*/
/**
* Method that can be used to collect all "real" introspectors that
* this introspector contains, if any; or this introspector
* if it is not a container. Used to get access to all container
* introspectors in their priority order.
*<p>
* Default implementation returns a Singleton list with this introspector
* as contents.
* This usually works for sub-classes, except for proxy or delegating "container
* introspectors" which need to override implementation.
*
* @return Collection of all introspectors starting with this one, in case
* multiple introspectors are chained
*/
public Collection<AnnotationIntrospector> allIntrospectors() {
return Collections.singletonList(this);
}
/**
* Method that can be used to collect all "real" introspectors that
* this introspector contains, if any; or this introspector
* if it is not a container. Used to get access to all container
* introspectors in their priority order.
*<p>
* Default implementation adds this introspector in result; this usually
* works for sub-classes, except for proxy or delegating "container
* introspectors" which need to override implementation.
*
* @param result Container to add introspectors to
*
* @return Passed in {@code Collection} filled with introspectors as explained
* above
*/
public Collection<AnnotationIntrospector> allIntrospectors(Collection<AnnotationIntrospector> result) {
result.add(this);
return result;
}
/*
/**********************************************************
/* Default Versioned impl
/**********************************************************
*/
@Override
public abstract Version version();
/*
/**********************************************************
/* Meta-annotations (annotations for annotation types)
/**********************************************************
*/
/**
* Method for checking whether given annotation is considered an
* annotation bundle: if so, all meta-annotations it has will
* be used instead of annotation ("bundle") itself.
*
* @param ann Annotated entity to introspect
*
* @return True if given annotation is considered an annotation
* bundle; false if not
*/
public boolean isAnnotationBundle(Annotation ann) {
return false;
}
/*
/**********************************************************
/* Annotations for Object Id handling
/**********************************************************
*/
/**
* Method for checking whether given annotated thing
* (type, or accessor) indicates that values
* referenced (values of type of annotated class, or
* values referenced by annotated property; latter
* having precedence) should include Object Identifier,
* and if so, specify details of Object Identity used.
*
* @param ann Annotated entity to introspect
*
* @return Details of Object Id as explained above, if Object Id
* handling to be applied; {@code null} otherwise.
*/
public ObjectIdInfo findObjectIdInfo(Annotated ann) {
return null;
}
/**
* Method for figuring out additional properties of an Object Identity reference
*
* @param ann Annotated entity to introspect
* @param objectIdInfo (optional) Base Object Id information, if any; {@code null} if none
*
* @return {@link ObjectIdInfo} augmented with possible additional information
*
* @since 2.1
*/
public ObjectIdInfo findObjectReferenceInfo(Annotated ann, ObjectIdInfo objectIdInfo) {
return objectIdInfo;
}
/*
/**********************************************************
/* General class annotations
/**********************************************************
*/
/**
* Method for locating name used as "root name" (for use by
* some serializers when outputting root-level object -- mostly
* for XML compatibility purposes) for given class, if one
* is defined. Returns null if no declaration found; can return
* explicit empty String, which is usually ignored as well as null.
*<p>
* NOTE: method signature changed in 2.1, to return {@link PropertyName}
* instead of String.
*
* @param ac Annotated class to introspect
*
* @return Root name to use, if any; {@code null} if not
*/
public PropertyName findRootName(AnnotatedClass ac) {
return null;
}
/**
* Method for checking whether properties that have specified type
* (class, not generics aware) should be completely ignored for
* serialization and deserialization purposes.
*
* @param ac Annotated class to introspect
*
* @return Boolean.TRUE if properties of type should be ignored;
* Boolean.FALSE if they are not to be ignored, null for default
* handling (which is 'do not ignore')
*/
public Boolean isIgnorableType(AnnotatedClass ac) { return null; }
/**
* Method for finding information about properties to ignore either by
* name, or by more general specification ("ignore all unknown").
* This method combines multiple aspects of ignorals and deprecates
* earlier methods such as
* {@link #findPropertiesToIgnore(Annotated, boolean)} and
* {@link #findIgnoreUnknownProperties(AnnotatedClass)}.
*
* @param config Configuration settings in effect (for serialization or deserialization)
* @param ann Annotated entity (Class, Accessor) to introspect
*
* @return Property ignoral settings to use;
* {@code JsonIgnoreProperties.Value.empty()} for defaults (should not return {@code null})
*
* @since 2.12 (to replace {@code findPropertyIgnorals()})
*/
public JsonIgnoreProperties.Value findPropertyIgnoralByName(MapperConfig<?> config, Annotated ann)
{
// In 2.12, remove redirection in future
return findPropertyIgnorals(ann);
}
/**
* Method for finding information about names of properties to included.
* This is typically used to strictly limit properties to include based
* on fully defined set of names ("allow-listing"), as opposed to excluding
* potential properties by exclusion ("deny-listing").
*
* @param config Configuration settings in effect (for serialization or deserialization)
* @param ann Annotated entity (Class, Accessor) to introspect
*
* @return Property inclusion settings to use;
* {@code JsonIncludeProperties.Value.all()} for defaults (should not return {@code null})
*
* @since 2.12
*/
public JsonIncludeProperties.Value findPropertyInclusionByName(MapperConfig<?> config, Annotated ann) {
return JsonIncludeProperties.Value.all();
}
/**
* Method for finding if annotated class has associated filter; and if so,
* to return id that is used to locate filter.
*
* @param ann Annotated entity to introspect
*
* @return Id of the filter to use for filtering properties of annotated
* class, if any; or null if none found.
*/
public Object findFilterId(Annotated ann) { return null; }
/**
* Method for finding {@link PropertyNamingStrategy} for given
* class, if any specified by annotations; and if so, either return
* a {@link PropertyNamingStrategy} instance, or Class to use for
* creating instance
*
* @param ac Annotated class to introspect
*
* @return Sub-class or instance of {@link PropertyNamingStrategy}, if one
* is specified for given class; null if not.
*
* @since 2.1
*/
public Object findNamingStrategy(AnnotatedClass ac) { return null; }
/**
* Method for finding {@link EnumNamingStrategy} for given
* class, if any specified by annotations; and if so, either return
* a {@link EnumNamingStrategy} instance, or Class to use for
* creating instance
*
* @param ac Annotated class to introspect
*
* @return Subclass or instance of {@link EnumNamingStrategy}, if one
* is specified for given class; null if not.
*
* @since 2.15
*/
public Object findEnumNamingStrategy(MapperConfig<?> config, AnnotatedClass ac) { return null; }
/**
* Method used to check whether specified class defines a human-readable
* description to use for documentation.
* There are no further definitions for contents; for example, whether
* these may be marked up using HTML (or something like wiki format like Markup)
* is not defined.
*
* @param ac Annotated class to introspect
*
* @return Human-readable description, if any.
*
* @since 2.7
*/
public String findClassDescription(AnnotatedClass ac) { return null; }
/**
* @param forSerialization True if requesting properties to ignore for serialization;
* false if for deserialization
* @param ac Annotated class to introspect
*
* @return Array of names of properties to ignore
*
* @since 2.6
*
* @deprecated Since 2.8, use {@link #findPropertyIgnoralByName} instead
*/
@Deprecated // since 2.8
public String[] findPropertiesToIgnore(Annotated ac, boolean forSerialization) {
return null;
}
/**
* Method for checking whether an annotation indicates that all unknown properties
* should be ignored.
*
* @param ac Annotated class to introspect
*
* @return True if class has something indicating "ignore [all] unknown properties"
*
* @deprecated Since 2.8, use {@link #findPropertyIgnoralByName} instead
*/
@Deprecated // since 2.8
public Boolean findIgnoreUnknownProperties(AnnotatedClass ac) { return null; }
/**
* @param ac Annotated class to introspect
*
* @since 2.8
* @deprecated 2.12, use {@link #findPropertyIgnoralByName} instead.
*
* @return Property ignoral settings to use;
* {@code JsonIgnoreProperties.Value.empty()} for defaults (should not return {@code null})
*/
@Deprecated // since 2.12
public JsonIgnoreProperties.Value findPropertyIgnorals(Annotated ac) {
return JsonIgnoreProperties.Value.empty();
}
/*
/**********************************************************
/* Property auto-detection
/**********************************************************
*/
/**
* Method for checking if annotations indicate changes to minimum visibility levels
* needed for auto-detecting property elements (fields, methods, constructors).
* A baseline checker is given, and introspector is to either return it as is
* (if no annotations are found), or build and return a derived instance (using
* checker's build methods).
*
* @param ac Annotated class to introspect
* @param checker Default visibility settings in effect before any override
*
* @return Visibility settings after possible annotation-based overrides
*/
public VisibilityChecker<?> findAutoDetectVisibility(AnnotatedClass ac,
VisibilityChecker<?> checker) {
return checker;
}
/*
/**********************************************************
/* Annotations for Polymorphic type handling
/**********************************************************
*/
/**
* Method for checking if given class has annotations that indicate
* that specific type resolver is to be used for handling instances.
* This includes not only
* instantiating resolver builder, but also configuring it based on
* relevant annotations (not including ones checked with a call to
* {@link #findSubtypes}
*
* @param config Configuration settings in effect (for serialization or deserialization)
* @param ac Annotated class to check for annotations
* @param baseType Base java type of value for which resolver is to be found
*
* @return Type resolver builder for given type, if one found; null if none
*/
public TypeResolverBuilder<?> findTypeResolver(MapperConfig<?> config,
AnnotatedClass ac, JavaType baseType) {
return null;
}
/**
* Method for checking if given property entity (field or method) has annotations
* that indicate that specific type resolver is to be used for handling instances.
* This includes not only
* instantiating resolver builder, but also configuring it based on
* relevant annotations (not including ones checked with a call to
* {@link #findSubtypes}
*
* @param config Configuration settings in effect (for serialization or deserialization)
* @param am Annotated member (field or method) to check for annotations
* @param baseType Base java type of property for which resolver is to be found
*
* @return Type resolver builder for properties of given entity, if one found;
* null if none
*/
public TypeResolverBuilder<?> findPropertyTypeResolver(MapperConfig<?> config,
AnnotatedMember am, JavaType baseType) {
return null;
}
/**
* Method for checking if given structured property entity (field or method that
* has nominal value of Map, Collection or array type) has annotations
* that indicate that specific type resolver is to be used for handling type
* information of contained values.
* This includes not only
* instantiating resolver builder, but also configuring it based on
* relevant annotations (not including ones checked with a call to
* {@link #findSubtypes}
*
* @param config Configuration settings in effect (for serialization or deserialization)
* @param am Annotated member (field or method) to check for annotations
* @param containerType Type of property for which resolver is to be found (must be a container type)
*
* @return Type resolver builder for values contained in properties of given entity,
* if one found; null if none
*/
public TypeResolverBuilder<?> findPropertyContentTypeResolver(MapperConfig<?> config,
AnnotatedMember am, JavaType containerType) {
return null;
}
/**
* Method for locating annotation-specified subtypes related to annotated
* entity (class, method, field). Note that this is only guaranteed to be
* a list of directly
* declared subtypes, no recursive processing is guarantees (i.e. caller
* has to do it if/as necessary)
*
* @param a Annotated entity (class, field/method) to check for annotations
*
* @return List of subtype definitions found if any; {@code null} if none
*/
public List<NamedType> findSubtypes(Annotated a) { return null; }
/**
* Method for checking if specified type has explicit name.
*
* @param ac Class to check for type name annotations
*
* @return Explicit type name (aka Type Id) found, if any; {@code null} if none
*/
public String findTypeName(AnnotatedClass ac) { return null; }
/**
* Method for checking whether given accessor claims to represent
* type id: if so, its value may be used as an override,
* instead of generated type id.
*
* @param am Annotated accessor (field/method/constructor parameter) to check for annotations
*
* @return Boolean to indicate whether member is a type id or not, if annotation
* found; {@code null} if no information found.
*/
public Boolean isTypeId(AnnotatedMember am) { return null; }
/*
/**********************************************************
/* General member (field, method/constructor) annotations
/**********************************************************
*/
/**
* Method for checking if given member indicates that it is part
* of a reference (parent/child).
*/
public ReferenceProperty findReferenceType(AnnotatedMember member) { return null; }
/**
* Method called to check whether given property is marked to be "unwrapped"
* when being serialized (and appropriately handled in reverse direction,
* i.e. expect unwrapped representation during deserialization).
* Return value is the name transformation to use, if wrapping/unwrapping
* should be done, or null if not -- note that transformation may simply
* be identity transformation (no changes).
*/
public NameTransformer findUnwrappingNameTransformer(AnnotatedMember member) { return null; }
/**
* Method called to check whether given property is marked to
* be ignored. This is used to determine whether to ignore
* properties, on per-property basis, usually combining
* annotations from multiple accessors (getters, setters, fields,
* constructor parameters).
*/
public boolean hasIgnoreMarker(AnnotatedMember m) { return false; }
/**
* Method called to find out whether given member expectes a value
* to be injected, and if so, what is the identifier of the value
* to use during injection.
* Type if identifier needs to be compatible with provider of
* values (of type {@link InjectableValues}); often a simple String
* id is used.
*
* @param m Member to check
*
* @return Identifier of value to inject, if any; null if no injection
* indicator is found
*
* @since 2.9
*/
public JacksonInject.Value findInjectableValue(AnnotatedMember m) {
// 05-Apr-2017, tatu: Just for 2.9, call deprecated method to help
// with some cases of overrides for legacy code
Object id = findInjectableValueId(m);
if (id != null) {
return JacksonInject.Value.forId(id);
}
return null;
}
/**
* Method that can be called to check whether this member has
* an annotation that suggests whether value for matching property
* is required or not.
*/
public Boolean hasRequiredMarker(AnnotatedMember m) { return null; }
/**
* Method for checking if annotated property (represented by a field or
* getter/setter method) has definitions for views it is to be included in.
* If null is returned, no view definitions exist and property is always
* included (or always excluded as per default view inclusion configuration);
* otherwise it will only be included for views included in returned
* array. View matches are checked using class inheritance rules (sub-classes
* inherit inclusions of super-classes)
*<p>
* Since 2.9 this method may also be called to find "default view(s)" for
* {@link AnnotatedClass}
*
* @param a Annotated property (represented by a method, field or ctor parameter)
* @return Array of views (represented by classes) that the property is included in;
* if null, always included (same as returning array containing <code>Object.class</code>)
*/
public Class<?>[] findViews(Annotated a) { return null; }
/**
* Method for finding format annotations for property or class.
* Return value is typically used by serializers and/or
* deserializers to customize presentation aspects of the
* serialized value.
*
* @since 2.1
*/
public JsonFormat.Value findFormat(Annotated memberOrClass) {
return JsonFormat.Value.empty();
}
/**
* Method used to check if specified property has annotation that indicates
* that it should be wrapped in an element; and if so, name to use.
* Note that not all serializers and deserializers support use this method:
* currently (2.1) it is only used by XML-backed handlers.
*
* @return Wrapper name to use, if any, or {@link PropertyName#USE_DEFAULT}
* to indicate that no wrapper element should be used.
*
* @since 2.1
*/
public PropertyName findWrapperName(Annotated ann) { return null; }
/**
* Method for finding suggested default value (as simple textual serialization)
* for the property. While core databind does not make any use of it, it is exposed
* for extension modules to use: an expected use is generation of schema representations
* and documentation.
*
* @since 2.5
*/
public String findPropertyDefaultValue(Annotated ann) { return null; }
/**
* Method used to check whether specified property member (accessor
* or mutator) defines human-readable description to use for documentation.
* There are no further definitions for contents; for example, whether
* these may be marked up using HTML is not defined.
*
* @return Human-readable description, if any.
*
* @since 2.3
*/
public String findPropertyDescription(Annotated ann) { return null; }
/**
* Method used to check whether specified property member (accessor
* or mutator) defines numeric index, and if so, what is the index value.
* Possible use cases for index values included use by underlying data format
* (some binary formats mandate use of index instead of name) and ordering
* of properties (for documentation, or during serialization).
*
* @since 2.4
*
* @return Explicitly specified index for the property, if any
*/
public Integer findPropertyIndex(Annotated ann) { return null; }
/**
* Method for finding implicit name for a property that given annotated
* member (field, method, creator parameter) may represent.
* This is different from explicit, annotation-based property name, in that
* it is "weak" and does not either proof that a property exists (for example,
* if visibility is not high enough), or override explicit names.
* In practice this method is used to introspect optional names for creator
* parameters (which may or may not be available and cannot be detected
* by standard databind); or to provide alternate name mangling for
* fields, getters and/or setters.
*
* @since 2.4
*/
public String findImplicitPropertyName(AnnotatedMember member) { return null; }
/**
* Method called to find if given property has alias(es) defined.
*
* @return `null` if member has no information; otherwise a `List` (possibly
* empty) of aliases to use.
*
* @since 2.9
*/
public List<PropertyName> findPropertyAliases(Annotated ann) { return null; }
/**
* Method for finding optional access definition for a property, annotated
* on one of its accessors. If a definition for read-only, write-only
* or read-write cases, visibility rules may be modified. Note, however,
* that even more specific annotations (like one for ignoring specific accessor)
* may further override behavior of the access definition.
*
* @since 2.6
*/
public JsonProperty.Access findPropertyAccess(Annotated ann) { return null; }
/**
* Method called in cases where a class has two methods eligible to be used
* for the same logical property, and default logic is not enough to figure
* out clear precedence. Introspector may try to choose one to use; or, if
* unable, return `null` to indicate it cannot resolve the problem.
*
* @since 2.7
*/
public AnnotatedMethod resolveSetterConflict(MapperConfig<?> config,
AnnotatedMethod setter1, AnnotatedMethod setter2) {
return null;
}
/**
* Method called on fields that are eligible candidates for properties
* (that is, non-static member fields), but not necessarily selected (may
* or may not be visible), to let fields affect name linking.
* Call will be made after finding implicit name (which by default is just
* name of the field, but may be overridden by introspector), but before
* discovering other accessors.
* If non-null name returned, it is to be used to find other accessors (getters,
* setters, creator parameters) and replace their implicit names with that
* of field's implicit name (assuming they differ).
*<p>
* Specific example (and initial use case is for support Kotlin's "is getter"
* matching (see
* <a href="https://kotlinlang.org/docs/reference/java-to-kotlin-interop.html">Kotling Interop</a>
* for details), in which field like '{@code isOpen}' would have implicit name of
* "isOpen", match getter {@code getOpen()} and setter {@code setOpen(boolean)},
* but use logical external name of "isOpen" (and not implicit name of getter/setter, "open"!).
* To achieve this, field implicit name needs to remain "isOpen" but this method needs
* to return name {@code PropertyName.construct("open")}: doing so will "pull in" getter
* and/or setter, and rename them as "isOpen".
*
* @param config Effective mapper configuration in use
* @param f Field to check
* @param implName Implicit name of the field; usually name of field itself but not always,
* used as the target name for accessors to rename.
*
* @return Name used to find other accessors to rename, if any; {@code null} to indicate
* no renaming
*
* @since 2.11
*/
public PropertyName findRenameByField(MapperConfig<?> config,
AnnotatedField f, PropertyName implName) {
return null;
}
/**
* @deprecated Since 2.9 Use {@link #findInjectableValue} instead
*/
@Deprecated // since 2.9
public Object findInjectableValueId(AnnotatedMember m) {
return null;
}
/*
/**********************************************************
/* Serialization: general annotations
/**********************************************************
*/
/**
* Method for getting a serializer definition on specified method
* or field. Type of definition is either instance (of type {@link JsonSerializer})
* or Class (of {@code Class<JsonSerializer>} implementation subtype);
* if value of different type is returned, a runtime exception may be thrown by caller.
*/
public Object findSerializer(Annotated am) {
return null;
}
/**
* Method for getting a serializer definition for keys of associated {@code java.util.Map} property.
* Type of definition is either instance (of type {@link JsonSerializer})
* or Class (of type {@code Class<JsonSerializer>});
* if value of different type is returned, a runtime exception may be thrown by caller.
*/
public Object findKeySerializer(Annotated am) {
return null;
}
/**
* Method for getting a serializer definition for content (values) of
* associated <code>Collection</code>, <code>array</code> or {@code Map} property.
* Type of definition is either instance (of type {@link JsonSerializer})
* or Class (of type {@code Class<JsonSerializer>});
* if value of different
* type is returned, a runtime exception may be thrown by caller.
*/
public Object findContentSerializer(Annotated am) {
return null;
}
/**
* Method for getting a serializer definition for serializer to use
* for nulls (null values) of associated property or type.
*
* @since 2.3
*/
public Object findNullSerializer(Annotated am) {
return null;
}
/**
* Method for accessing declared typing mode annotated (if any).
* This is used for type detection, unless more granular settings
* (such as actual exact type; or serializer to use which means
* no type information is needed) take precedence.
*
* @return Typing mode to use, if annotation is found; null otherwise
*/
public JsonSerialize.Typing findSerializationTyping(Annotated a) {
return null;
}
/**
* Method for finding {@link Converter} that annotated entity
* (property or class) has indicated to be used as part of
* serialization. If not null, either has to be actual
* {@link Converter} instance, or class for such converter;
* and resulting converter will be used first to convert property
* value to converter target type, and then serializer for that
* type is used for actual serialization.
*<p>
* This feature is typically used to convert internal values into types
* that Jackson can convert.
*<p>
* Note also that this feature does not necessarily work well with polymorphic
* type handling, or object identity handling; if such features are needed
* an explicit serializer is usually better way to handle serialization.
*
* @param a Annotated property (field, method) or class to check for
* annotations
*
* @since 2.2
*/
public Object findSerializationConverter(Annotated a) {
return null;
}
/**
* Method for finding {@link Converter} that annotated property
* has indicated needs to be used for values of container type
* (this also means that method should only be called for properties
* of container types, List/Map/array properties).
*<p>
* If not null, either has to be actual
* {@link Converter} instance, or class for such converter;
* and resulting converter will be used first to convert property
* value to converter target type, and then serializer for that
* type is used for actual serialization.
*<p>
* Other notes are same as those for {@link #findSerializationConverter}
*
* @param a Annotated property (field, method) to check.
*
* @since 2.2
*/
public Object findSerializationContentConverter(AnnotatedMember a) {
return null;
}
/**
* Method for checking inclusion criteria for a type (Class) or property (yes, method
* name is bit unfortunate -- not just for properties!).
* In case of class, acts as the default for properties POJO contains; for properties
* acts as override for class defaults and possible global defaults.
*
* @since 2.6
*/
public JsonInclude.Value findPropertyInclusion(Annotated a) {
return JsonInclude.Value.empty();
}
/*
/**********************************************************
/* Serialization: type refinements
/**********************************************************
*/
/**
* Method called to find out possible type refinements to use
* for deserialization, including not just value itself but
* key and/or content type, if type has those.
*
* @since 2.7
*/
public JavaType refineSerializationType(final MapperConfig<?> config,
final Annotated a, final JavaType baseType) throws JsonMappingException
{
return baseType;
}
/*
/**********************************************************
/* Serialization: class annotations
/**********************************************************
*/
/**
* Method for accessing defined property serialization order (which may be
* partial). May return null if no ordering is defined.
*/
public String[] findSerializationPropertyOrder(AnnotatedClass ac) {
return null;
}
/**
* Method for checking whether an annotation indicates that serialized properties
* for which no explicit is defined should be alphabetically (lexicograpically)
* ordered
*/
public Boolean findSerializationSortAlphabetically(Annotated ann) {
return null;
}
/**
* Method for adding possible virtual properties to be serialized along
* with regular properties.
*
* @since 2.5
*/
public void findAndAddVirtualProperties(MapperConfig<?> config, AnnotatedClass ac,
List<BeanPropertyWriter> properties) { }
/*
/**********************************************************
/* Serialization: property annotations
/**********************************************************
*/
/**
* Method for checking whether given property accessors (method,
* field) has an annotation that suggests property name to use
* for serialization.
* Should return null if no annotation
* is found; otherwise a non-null name (possibly
* {@link PropertyName#USE_DEFAULT}, which means "use default heuristics").
*
* @param a Property accessor to check
*
* @return Name to use if found; null if not.
*
* @since 2.1
*/
public PropertyName findNameForSerialization(Annotated a) {
return null;
}
/**
* Method for checking whether given method has an annotation
* that suggests the return value of annotated field or method
* should be used as "the key" of the object instance; usually
* serialized as a primitive value such as String or number.
*
* @return {@link Boolean#TRUE} if such annotation is found and is not disabled;
* {@link Boolean#FALSE} if disabled annotation (block) is found (to indicate
* accessor is definitely NOT to be used "as value"); or `null` if no
* information found.
*
* @since 2.12
*/
public Boolean hasAsKey(MapperConfig<?> config, Annotated a) {
return null;
}
/**
* Method for checking whether given method has an annotation
* that suggests that the return value of annotated method
* should be used as "the value" of the object instance; usually
* serialized as a primitive value such as String or number.
*
* @return {@link Boolean#TRUE} if such annotation is found and is not disabled;
* {@link Boolean#FALSE} if disabled annotation (block) is found (to indicate
* accessor is definitely NOT to be used "as value"); or `null` if no
* information found.
*
* @since 2.9
*/
public Boolean hasAsValue(Annotated a) {
// 20-Nov-2016, tatu: Delegate in 2.9; remove redirect from later versions
if (a instanceof AnnotatedMethod) {
if (hasAsValueAnnotation((AnnotatedMethod) a)) {
return true;
}
}
return null;
}
/**
* Method for checking whether given method has an annotation
* that suggests that the method is to serve as "any setter";
* method to be used for accessing set of miscellaneous "extra"
* properties, often bound with matching "any setter" method.
*
* @param ann Annotated entity to check
*
* @return True if such annotation is found (and is not disabled),
* false otherwise
*
* @since 2.9
*/
public Boolean hasAnyGetter(Annotated ann) {
// 21-Nov-2016, tatu: Delegate in 2.9; remove redirect from later versions
if (ann instanceof AnnotatedMethod) {
if (hasAnyGetterAnnotation((AnnotatedMethod) ann)) {
return true;
}
}
return null;
}
/**
* Method for efficiently figuring out which if given set of <code>Enum</code> values
* have explicitly defined name. Method will overwrite entries in incoming <code>names</code>
* array with explicit names found, if any, leaving other entries unmodified.
*
* @param enumType Type of Enumeration
* @param enumValues Values of enumeration
* @param names Matching declared names of enumeration values (with indexes
* matching {@code enumValues} entries)
*
* @return Array of names to use (possible {@code names} passed as argument)
*
* @since 2.7
*/
public String[] findEnumValues(Class<?> enumType, Enum<?>[] enumValues, String[] names) {
// 18-Oct-2016, tatu: In 2.8 delegated to deprecated method; not so in 2.9 and beyond
return names;
}
/**
* Method that is related to {@link #findEnumValues} but is called to check if
* there are alternative names (aliased) that can be accepted for entries, in
* addition to primary names introspected earlier.
* If so, these aliases should be returned in {@code aliases} {@link List} passed
* as argument (and initialized for proper size by caller).
*
* @param enumType Type of Enumeration
* @param enumValues Values of enumeration
* @param aliases (in/out) Pre-allocated array where aliases found, if any, may be
* added (in indexes matching those of {@code enumValues})
*
* @since 2.11
*/
public void findEnumAliases(Class<?> enumType, Enum<?>[] enumValues, String[][] aliases) {
;
}
/**
* Finds the Enum value that should be considered the default value, if possible.
*
* @param enumCls The Enum class to scan for the default value
*
* @return null if none found or it's not possible to determine one
*
* @since 2.8
*/
public Enum<?> findDefaultEnumValue(Class<Enum<?>> enumCls) {
return null;
}
/**
* Method for determining the String value to use for serializing
* given enumeration entry; used when serializing enumerations
* as Strings (the standard method).
*
* @param value Enum value to introspect
*
* @return Serialized enum value.
*
* @deprecated Since 2.8: use {@link #findEnumValues} instead because this method
* does not properly handle override settings (defaults to <code>enum.name</code>
* without indicating whether that is explicit or not), and is inefficient to
* call one-by-one.
*/
@Deprecated
public String findEnumValue(Enum<?> value) {
return value.name();
}
/**
* @param am Annotated method to check
*
* @deprecated Since 2.9 Use {@link #hasAsValue(Annotated)} instead.
*/
@Deprecated // since 2.9
public boolean hasAsValueAnnotation(AnnotatedMethod am) {
return false;
}
/**
* @param am Annotated method to check
*
* @deprecated Since 2.9 Use {@link #hasAnyGetter} instead
*/
@Deprecated
public boolean hasAnyGetterAnnotation(AnnotatedMethod am) {
return false;
}
/*
/**********************************************************
/* Deserialization: general annotations
/**********************************************************
*/
/**
* Method for getting a deserializer definition on specified method
* or field.
* Type of definition is either instance (of type {@link JsonDeserializer})
* or Class (of type {@code Class&<JsonDeserializer>});
* type is returned, a runtime exception may be thrown by caller.
*/
public Object findDeserializer(Annotated am) {
return null;
}
/**
* Method for getting a deserializer definition for keys of
* associated <code>Map</code> property.
* Type of definition is either instance (of type {@link JsonDeserializer})
* or Class (of type {@code Class<JsonDeserializer>});
* if value of different
* type is returned, a runtime exception may be thrown by caller.
*/
public Object findKeyDeserializer(Annotated am) {
return null;
}
/**
* Method for getting a deserializer definition for content (values) of
* associated <code>Collection</code>, <code>array</code> or
* <code>Map</code> property.
* Type of definition is either instance (of type {@link JsonDeserializer})
* or Class (of type {@code Class<JsonDeserializer>});
* if value of different
* type is returned, a runtime exception may be thrown by caller.
*/
public Object findContentDeserializer(Annotated am) {
return null;
}
/**
* Method for finding {@link Converter} that annotated entity
* (property or class) has indicated to be used as part of
* deserialization.
* If not null, either has to be actual
* {@link Converter} instance, or class for such converter;
* and resulting converter will be used after Jackson has deserializer
* data into intermediate type (Converter input type), and Converter
* needs to convert this into its target type to be set as property value.
*<p>
* This feature is typically used to convert intermediate Jackson types
* (that default deserializers can produce) into custom type instances.
*<p>
* Note also that this feature does not necessarily work well with polymorphic
* type handling, or object identity handling; if such features are needed
* an explicit deserializer is usually better way to handle deserialization.
*
* @param a Annotated property (field, method) or class to check for
* annotations
*
* @since 2.2
*/
public Object findDeserializationConverter(Annotated a) {
return null;
}
/**
* Method for finding {@link Converter} that annotated property
* has indicated needs to be used for values of container type
* (this also means that method should only be called for properties
* of container types, List/Map/array properties).
*<p>
* If not null, either has to be actual
* {@link Converter} instance, or class for such converter;
* and resulting converter will be used after Jackson has deserializer
* data into intermediate type (Converter input type), and Converter
* needs to convert this into its target type to be set as property value.
*<p>
* Other notes are same as those for {@link #findDeserializationConverter}
*
* @param a Annotated property (field, method) to check.
*
* @since 2.2
*/
public Object findDeserializationContentConverter(AnnotatedMember a) {
return null;
}
/*
/**********************************************************
/* Deserialization: type refinements
/**********************************************************
*/
/**
* Method called to find out possible type refinements to use
* for deserialization.
*
* @since 2.7
*/
public JavaType refineDeserializationType(final MapperConfig<?> config,
final Annotated a, final JavaType baseType) throws JsonMappingException
{
return baseType;
}
/*
/**********************************************************
/* Deserialization: class annotations
/**********************************************************
*/
/**
* Method getting {@link ValueInstantiator} to use for given
* type (class): return value can either be an instance of
* instantiator, or class of instantiator to create.
*
* @param ac Annotated class to introspect
*
* @return Either {@link ValueInstantiator} instance to use, or
* {@link Class} of one to create; or {@code null} if no annotations
* found to indicate custom value instantiator.
*/
public Object findValueInstantiator(AnnotatedClass ac) {
return null;
}
/**
* Method for finding Builder object to use for constructing
* value instance and binding data (sort of combining value
* instantiators that can construct, and deserializers
* that can bind data).
*<p>
* Note that unlike accessors for some helper Objects, this
* method does not allow returning instances: the reason is
* that builders have state, and a separate instance needs
* to be created for each deserialization call.
*
* @param ac Annotated class to introspect
*
* @return Builder class to use, if annotation found; {@code null} if not.
*
* @since 2.0
*/
public Class<?> findPOJOBuilder(AnnotatedClass ac) {
return null;
}
/**
* @param ac Annotated class to introspect
*
* @return Builder settings to use, if any found; {@code null} if not.
*
* @since 2.0
*/
public JsonPOJOBuilder.Value findPOJOBuilderConfig(AnnotatedClass ac) {
return null;
}
/*
/**********************************************************
/* Deserialization: property annotations
/**********************************************************
*/
/**
* Method for checking whether given property accessors (method,
* field) has an annotation that suggests property name to use
* for deserialization (reading JSON into POJOs).
* Should return null if no annotation
* is found; otherwise a non-null name (possibly
* {@link PropertyName#USE_DEFAULT}, which means "use default heuristics").
*
* @param ann Annotated entity to check
*
* @return Name to use if found; {@code null} if not.
*
* @since 2.1
*/
public PropertyName findNameForDeserialization(Annotated ann) {
return null;
}
/**
* Method for checking whether given method has an annotation
* that suggests that the method is to serve as "any setter";
* method to be used for setting values of any properties for
* which no dedicated setter method is found.
*
* @param ann Annotated entity to check
*
* @return {@code Boolean.TRUE} or {@code Boolean.FALSE} if explicit
* "any setter" marker found; {@code null} otherwise.
*
* @since 2.9
*/
public Boolean hasAnySetter(Annotated ann) {
return null;
}
/**
* Method for finding possible settings for property, given annotations
* on an accessor.
*
* @param ann Annotated entity to check
*
* @return Setter info value found, if any;
* {@code JsonSetter.Value.empty()} if none (should not return {@code null})
*
* @since 2.9
*/
public JsonSetter.Value findSetterInfo(Annotated ann) {
return JsonSetter.Value.empty();
}
/**
* Method for finding merge settings for property, if any.
*
* @param ann Annotated entity to check
*
* @return {@code Boolean.TRUE} or {@code Boolean.FALSE} if explicit
* merge enable/disable found; {@code null} otherwise.
*
* @since 2.9
*/
public Boolean findMergeInfo(Annotated ann) {
return null;
}
/**
* Method called to check whether potential Creator (constructor or static factory
* method) has explicit annotation to indicate it as actual Creator; and if so,
* which {@link com.fasterxml.jackson.annotation.JsonCreator.Mode} to use.
*<p>
* NOTE: caller needs to consider possibility of both `null` (no annotation found)
* and {@link com.fasterxml.jackson.annotation.JsonCreator.Mode#DISABLED} (annotation found,
* but disabled); latter is necessary as marker in case multiple introspectors are chained,
* as well as possibly as when using mix-in annotations.
*
* @param config Configuration settings in effect (for serialization or deserialization)
* @param ann Annotated accessor (usually constructor or static method) to check
*
* @return Creator mode found, if any; {@code null} if none
*
* @since 2.9
*/
public JsonCreator.Mode findCreatorAnnotation(MapperConfig<?> config, Annotated ann) {
// 13-Sep-2016, tatu: for backwards compatibility, implement using delegation
/// (remove from version AFTER 2.9)
if (hasCreatorAnnotation(ann)) {
JsonCreator.Mode mode = findCreatorBinding(ann);
if (mode == null) {
mode = JsonCreator.Mode.DEFAULT;
}
return mode;
}
return null;
}
/**
* Method for checking whether given annotated item (method, constructor)
* has an annotation
* that suggests that the method is a "creator" (aka factory)
* method to be used for construct new instances of deserialized
* values.
*
* @param ann Annotated entity to check
*
* @return True if such annotation is found (and is not disabled),
* false otherwise
*
* @deprecated Since 2.9 use {@link #findCreatorAnnotation} instead.
*/
@Deprecated
public boolean hasCreatorAnnotation(Annotated ann) {
return false;
}
/**
* Method for finding indication of creator binding mode for
* a creator (something for which {@link #hasCreatorAnnotation} returns
* true), for cases where there may be ambiguity (currently: single-argument
* creator with implicit but no explicit name for the argument).
*
* @param ann Annotated entity to check
*
* @return Creator mode found, if any; {@code null} if none
*
* @since 2.5
* @deprecated Since 2.9 use {@link #findCreatorAnnotation} instead.
*/
@Deprecated
public JsonCreator.Mode findCreatorBinding(Annotated ann) {
return null;
}
/**
* @param am Annotated method to check
*
* @deprecated Since 2.9 use {@link #hasAnySetter} instead.
*
* @return {@code true} if "any-setter" annotation was found; {@code false} otherwise
*/
@Deprecated // since 2.9
public boolean hasAnySetterAnnotation(AnnotatedMethod am) {
return false;
}
/*
/**********************************************************
/* Overridable methods: may be used as low-level extension
/* points.
/**********************************************************
*/
/**
* Method that should be used by sub-classes for ALL
* annotation access;
* overridable so
* that sub-classes may, if they choose to, mangle actual access to
* block access ("hide" annotations) or perhaps change it.
*<p>
* Default implementation is simply:
*<code>
* return annotated.getAnnotation(annoClass);
*</code>
*
* @param <A> Annotation type being checked
* @param ann Annotated entity to check for specified annotation
* @param annoClass Type of annotation to find
*
* @return Value of given annotation (as per {@code annoClass}), if entity
* has one; {@code null} otherwise
*
* @since 2.5
*/
protected <A extends Annotation> A _findAnnotation(Annotated ann,
Class<A> annoClass) {
return ann.getAnnotation(annoClass);
}
/**
* Method that should be used by sub-classes for ALL
* annotation existence access;
* overridable so that sub-classes may, if they choose to, mangle actual access to
* block access ("hide" annotations) or perhaps change value seen.
*<p>
* Default implementation is simply:
*<code>
* return annotated.hasAnnotation(annoClass);
*</code>
*
* @param ann Annotated entity to check for specified annotation
* @param annoClass Type of annotation to find
*
* @return {@code true} if specified annotation exists in given entity; {@code false} if not
*
* @since 2.5
*/
protected boolean _hasAnnotation(Annotated ann, Class<? extends Annotation> annoClass) {
return ann.hasAnnotation(annoClass);
}
/**
* Alternative lookup method that is used to see if annotation has at least one of
* annotations of types listed in second argument.
*
* @param ann Annotated entity to check for specified annotation
* @param annoClasses Types of annotation to find
*
* @return {@code true} if at least one of specified annotation exists in given entity;
* {@code false} otherwise
*
* @since 2.7
*/
protected boolean _hasOneOf(Annotated ann, Class<? extends Annotation>[] annoClasses) {
return ann.hasOneOf(annoClasses);
}
}