Module tools.jackson.databind

Package tools.jackson.databind

Class JavaType

java.lang.Object

tools.jackson.core.type.ResolvedType

tools.jackson.databind.JavaType

All Implemented Interfaces:

Serializable, Type

Direct Known Subclasses:

TypeBase

public abstract class JavaType
extends ResolvedType
implements Serializable, Type

Base class for type token classes used both to contain information and as keys for deserializers.

Instances can (only) be constructed by TypeFactory.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected final boolean	_asStatic	Whether entities defined with this type should be handled using static typing (as opposed to dynamic runtime type) or not.
protected final Class<?>	_class	This is the nominal type-erased Class that would be close to the type represented (but not exactly type, due to type erasure: type instance may have more information on this).
protected final int	_hash
protected final Object	_typeHandler	Optional handler that can be attached to indicate how to handle additional type metadata associated with this type.
protected final Object	_valueHandler	Optional handler (codec) that can be attached to indicate what to use for handling (serializing, deserializing) values of this specific type.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	JavaType(Class<?> raw, int additionalHash, Object valueHandler, Object typeHandler, boolean asStatic)	Main base constructor for sub-classes to use
protected	JavaType(JavaType base)	Copy-constructor used when refining/upgrading type instances.

Method Summary

Modifier and Type	Method	Description
abstract JavaType	containedType(int index)
abstract int	containedTypeCount()
JavaType	containedTypeOrUnknown(int index)	Convenience method that is functionally same as: JavaType t = containedType(index); if (t == null) { t = TypeFactory.unknownType(); } and typically used to eliminate need for null checks for common case where we just want to check if containedType is available first; and if not, use "unknown type" (which translates to java.lang.Object basically).
abstract boolean	equals(Object o)
abstract JavaType	findSuperType(Class<?> erasedTarget)	Method that may be called to find representation of given type within type hierarchy of this type: either this type (if this type has given erased type), one of its supertypes that has the erased types, or null if target is neither this type or any of its supertypes.
abstract JavaType[]	findTypeParameters(Class<?> expType)	Method that may be used to find paramaterization this type has for given type-erased generic target type.
abstract TypeBindings	getBindings()
JavaType	getContentType()
Object	getContentTypeHandler()	Internal accessor that should not be used by any code outside of jackson-databind: only used internally by databind.
Object	getContentValueHandler()	Internal accessor that should not be used by any code outside of jackson-databind: only used internally by databind.
String	getErasedSignature()	Method for accessing signature without generic type information, in form compatible with all versions of JVM, and specifically used for type descriptions when generating byte code.
abstract StringBuilder	getErasedSignature(StringBuilder sb)	Method for accessing signature without generic type information, in form compatible with all versions of JVM, and specifically used for type descriptions when generating byte code.
String	getGenericSignature()	Method for accessing signature that contains generic type information, in form compatible with JVM 1.5 as per JLS.
abstract StringBuilder	getGenericSignature(StringBuilder sb)
abstract List<JavaType>	getInterfaces()	Accessor for finding fully resolved interfaces this type implements, if any; empty array if none.
JavaType	getKeyType()
final Class<?>	getRawClass()
JavaType	getReferencedType()
abstract JavaType	getSuperClass()	Accessor for finding fully resolved parent class of this type, if it has one; null if not.
Object	getTypeHandler()	Internal accessor that should not be used by any code outside of jackson-databind: only used internally by databind.
Object	getValueHandler()	Internal accessor that should not be used by any code outside of jackson-databind: only used internally by databind.
boolean	hasContentType()	Accessor that allows determining whether getContentType() should return a non-null value (that is, there is a "content type") or not.
boolean	hasGenericTypes()
boolean	hasHandlers()	Helper method that checks whether this type, or its (optional) key or content type has getValueHandler() or getTypeHandler(); that is, are there any non-standard handlers associated with this type object.
int	hashCode()
final boolean	hasRawClass(Class<?> clz)	Method that can be used to check whether this type has specified Class as its type erasure.
boolean	hasValueHandler()
boolean	isAbstract()
boolean	isArrayType()
boolean	isCollectionLikeType()
boolean	isConcrete()	Convenience method for checking whether underlying Java type is a concrete class or not: abstract classes and interfaces are not.
abstract boolean	isContainerType()
final boolean	isEnumImplType()	Similar to isEnumType() except does NOT return true for Enum (since that is not Enum implementation type).
final boolean	isEnumType()	Method that basically does equivalent of:
final boolean	isFinal()
final boolean	isInterface()
boolean	isIterationType()	Method that returns true if this instance is of type IterationType.
final boolean	isJavaLangObject()	Convenience method, short-hand for getRawClass() == Object.class and used to figure if we basically have "untyped" type object.
boolean	isMapLikeType()
final boolean	isPrimitive()
final boolean	isRecordType()
boolean	isThrowable()
final boolean	isTypeOrSubTypeOf(Class<?> clz)
final boolean	isTypeOrSuperTypeOf(Class<?> clz)
abstract JavaType	refine(Class<?> rawType, TypeBindings bindings, JavaType superClass, JavaType[] superInterfaces)	Mutant factory method that will try to create and return a sub-type instance for known parameterized types; for other types will return `null` to indicate that no just refinement makes necessary sense, without trying to detect special status through implemented interfaces.
abstract String	toString()
final boolean	useStaticType()	Accessor for checking whether handlers for dealing with values of this type should use static typing (as opposed to dynamic typing).
abstract JavaType	withContentType(JavaType contentType)	Mutant factory method that may be called on structured types that have a so-called content type (element of arrays, value type of Maps, referenced type of referential types), and will construct a new instance that is identical to this instance, except that it has specified content type, instead of current one.
abstract JavaType	withContentTypeHandler(Object h)	Internal method that should not be used by any code outside of jackson-databind: only used internally by databind.
abstract JavaType	withContentValueHandler(Object h)	Internal method that should not be used by any code outside of jackson-databind: only used internally by databind.
JavaType	withHandlersFrom(JavaType src)	Internal method that should not be used by any code outside of jackson-databind: only used internally by databind.
abstract JavaType	withStaticTyping()	Method that can be called to get a type instance that indicates that values of the type should be handled using "static typing" for purposes of serialization (as opposed to "dynamic" aka runtime typing): meaning that no runtime information is needed for determining serializers to use.
abstract JavaType	withTypeHandler(Object h)	Internal method that should not be used by any code outside of jackson-databind: only used internally by databind.
abstract JavaType	withValueHandler(Object h)	Internal method that should not be used by any code outside of jackson-databind: only used internally by databind.

Methods inherited from class tools.jackson.core.type.ResolvedType

isReferenceType, toCanonical

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.reflect.Type

getTypeName

Field Details

_class

protected final Class<?> _class

This is the nominal type-erased Class that would be close to the type represented (but not exactly type, due to type erasure: type instance may have more information on this). May be an interface or abstract class, so instantiation may not be possible.

_hash

protected final int _hash

_valueHandler

protected final Object _valueHandler

Optional handler (codec) that can be attached to indicate what to use for handling (serializing, deserializing) values of this specific type.

Note: untyped (i.e. caller has to cast) because it is used for different kinds of handlers, with unrelated types.

_typeHandler

protected final Object _typeHandler

Optional handler that can be attached to indicate how to handle additional type metadata associated with this type.

Note: untyped (i.e. caller has to cast) because it is used for different kinds of handlers, with unrelated types.

_asStatic

protected final boolean _asStatic

Whether entities defined with this type should be handled using static typing (as opposed to dynamic runtime type) or not.

Constructor Details

JavaType

protected JavaType(Class<?> raw,
 int additionalHash,
 Object valueHandler,
 Object typeHandler,
 boolean asStatic)

Main base constructor for sub-classes to use

Parameters:

raw - "Raw" (type-erased) class for this type

additionalHash - Additional hash code to use, in addition to hash code of the class name

valueHandler - internal handler (serializer/deserializer) to apply for this type

typeHandler - internal type handler (type serializer/deserializer) to apply for this type

asStatic - Whether this type declaration will force specific type as opposed to being a base type (usually for serialization typing)

JavaType

protected JavaType(JavaType base)

Copy-constructor used when refining/upgrading type instances.

Method Details

withContentType

public abstract JavaType withContentType(JavaType contentType)

Mutant factory method that may be called on structured types that have a so-called content type (element of arrays, value type of Maps, referenced type of referential types), and will construct a new instance that is identical to this instance, except that it has specified content type, instead of current one. If content type is already set to given type, this is returned. If type does not have a content type (which is the case with SimpleType), IllegalArgumentException will be thrown.

Returns:

Newly created type instance

withStaticTyping

public abstract JavaType withStaticTyping()

Method that can be called to get a type instance that indicates that values of the type should be handled using "static typing" for purposes of serialization (as opposed to "dynamic" aka runtime typing): meaning that no runtime information is needed for determining serializers to use. The main use case is to allow forcing of specific root value serialization type, and specifically in resolving serializers for contained types (element types for arrays, Collections and Maps).

withTypeHandler

public abstract JavaType withTypeHandler(Object h)

Internal method that should not be used by any code outside of jackson-databind: only used internally by databind. May be removed from Jackson 3.0.

This mutant factory method will construct a new instance that is identical to this instance, except that it will have specified type handler assigned.

Parameters:

h - Handler to pass to new instance created

Returns:

Newly created type instance with same type information, specified handler

withContentTypeHandler

public abstract JavaType withContentTypeHandler(Object h)

Internal method that should not be used by any code outside of jackson-databind: only used internally by databind. May be removed from Jackson 3.0.

This mutant factory method will construct a new instance that is identical to this instance, except that it will have specified content type (element type for arrays, value type for Maps and so forth) handler assigned.

Parameters:

h - Handler to pass to new instance created

Returns:

Newly created type instance with same type information, specified handler

withValueHandler

public abstract JavaType withValueHandler(Object h)

Internal method that should not be used by any code outside of jackson-databind: only used internally by databind. May be removed from Jackson 3.0.

This mutant factory method will construct a new instance that is identical to this instance, except that it will have specified value handler assigned.

Parameters:

h - Handler to pass to new instance created

Returns:

Newly created type instance with same type information, specified handler

withContentValueHandler

public abstract JavaType withContentValueHandler(Object h)

Internal method that should not be used by any code outside of jackson-databind: only used internally by databind. May be removed from Jackson 3.0.

Mutant factory method that will construct a new instance that is identical to this instance, except that it will have specified content value handler assigned.

Parameters:

h - Handler to pass to new instance created

Returns:

Newly created type instance with same type information, specified handler

withHandlersFrom

public JavaType withHandlersFrom(JavaType src)

Internal method that should not be used by any code outside of jackson-databind: only used internally by databind. May be removed from Jackson 3.0.

Mutant factory method that will try to copy handlers that the specified source type instance had, if any; this must be done recursively where necessary (as content types may be structured).

refine

public abstract JavaType refine(Class<?> rawType,
 TypeBindings bindings,
 JavaType superClass,
 JavaType[] superInterfaces)

Mutant factory method that will try to create and return a sub-type instance for known parameterized types; for other types will return `null` to indicate that no just refinement makes necessary sense, without trying to detect special status through implemented interfaces.

getRawClass

public final Class<?> getRawClass()

Specified by:

getRawClass in class ResolvedType

hasRawClass

public final boolean hasRawClass(Class<?> clz)

Method that can be used to check whether this type has specified Class as its type erasure. Put another way, returns true if instantiation of this Type is given (type-erased) Class.

Specified by:

hasRawClass in class ResolvedType

hasContentType

public boolean hasContentType()

Accessor that allows determining whether getContentType() should return a non-null value (that is, there is a "content type") or not. True if isContainerType() or ResolvedType.isReferenceType() return true.

isTypeOrSubTypeOf

public final boolean isTypeOrSubTypeOf(Class<?> clz)

isTypeOrSuperTypeOf

public final boolean isTypeOrSuperTypeOf(Class<?> clz)

isAbstract

public boolean isAbstract()

Specified by:

isAbstract in class ResolvedType

isConcrete

public boolean isConcrete()

Convenience method for checking whether underlying Java type is a concrete class or not: abstract classes and interfaces are not.

Specified by:

isConcrete in class ResolvedType

isThrowable

public boolean isThrowable()

Specified by:

isThrowable in class ResolvedType

isArrayType

public boolean isArrayType()

Specified by:

isArrayType in class ResolvedType

isEnumType

public final boolean isEnumType()

Method that basically does equivalent of:

  Enum.class.isAssignableFrom(getRawClass())

that is, return true if the underlying type erased class is Enum or one its subtypes (Enum implementations).

Specified by:

isEnumType in class ResolvedType

isEnumImplType

public final boolean isEnumImplType()

Similar to isEnumType() except does NOT return true for Enum (since that is not Enum implementation type).

isRecordType

public final boolean isRecordType()

Since:

2.12

isIterationType

public boolean isIterationType()

Method that returns true if this instance is of type IterationType.

Returns:

True if this type is considered "iteration type"

Since:

2.16

isInterface

public final boolean isInterface()

Specified by:

isInterface in class ResolvedType

isPrimitive

public final boolean isPrimitive()

Specified by:

isPrimitive in class ResolvedType

isFinal

public final boolean isFinal()

Specified by:

isFinal in class ResolvedType

isContainerType

public abstract boolean isContainerType()

Specified by:

isContainerType in class ResolvedType

Returns:

True if type represented is a container type; this includes array, Map and Collection types.

isCollectionLikeType

public boolean isCollectionLikeType()

Specified by:

isCollectionLikeType in class ResolvedType

Returns:

True if type is either true Collection type, or something similar (meaning it has at least one type parameter, which describes type of contents)

isMapLikeType

public boolean isMapLikeType()

Specified by:

isMapLikeType in class ResolvedType

Returns:

True if type is either true Map type, or something similar (meaning it has at least two type parameter; first one describing key type, second value type)

isJavaLangObject

public final boolean isJavaLangObject()

Convenience method, short-hand for getRawClass() == Object.class and used to figure if we basically have "untyped" type object.

useStaticType

public final boolean useStaticType()

Accessor for checking whether handlers for dealing with values of this type should use static typing (as opposed to dynamic typing). Note that while value of 'true' does mean that static typing is to be used, value of 'false' may still be overridden by other settings.

hasGenericTypes

public boolean hasGenericTypes()

Specified by:

hasGenericTypes in class ResolvedType

getKeyType

public JavaType getKeyType()

Specified by:

getKeyType in class ResolvedType

getContentType

public JavaType getContentType()

Specified by:

getContentType in class ResolvedType

getReferencedType

public JavaType getReferencedType()

Specified by:

getReferencedType in class ResolvedType

containedTypeCount

public abstract int containedTypeCount()

Specified by:

containedTypeCount in class ResolvedType

containedType

public abstract JavaType containedType(int index)

Specified by:

containedType in class ResolvedType

containedTypeOrUnknown

public JavaType containedTypeOrUnknown(int index)

Convenience method that is functionally same as: JavaType t = containedType(index); if (t == null) { t = TypeFactory.unknownType(); } and typically used to eliminate need for null checks for common case where we just want to check if containedType is available first; and if not, use "unknown type" (which translates to java.lang.Object basically).

getBindings

public abstract TypeBindings getBindings()

findSuperType

public abstract JavaType findSuperType(Class<?> erasedTarget)

Method that may be called to find representation of given type within type hierarchy of this type: either this type (if this type has given erased type), one of its supertypes that has the erased types, or null if target is neither this type or any of its supertypes.

getSuperClass

public abstract JavaType getSuperClass()

Accessor for finding fully resolved parent class of this type, if it has one; null if not.

getInterfaces

public abstract List<JavaType> getInterfaces()

Accessor for finding fully resolved interfaces this type implements, if any; empty array if none.

findTypeParameters

public abstract JavaType[] findTypeParameters(Class<?> expType)

Method that may be used to find paramaterization this type has for given type-erased generic target type.

getValueHandler

public Object getValueHandler()

Internal accessor that should not be used by any code outside of jackson-databind: only used internally by databind. May be removed from Jackson 3.0.

Returns:

Value handler associated with this type, if any.

getTypeHandler

public Object getTypeHandler()

Internal accessor that should not be used by any code outside of jackson-databind: only used internally by databind. May be removed from Jackson 3.0.

Returns:

Type handler associated with this type, if any.

getContentValueHandler

public Object getContentValueHandler()

Internal accessor that should not be used by any code outside of jackson-databind: only used internally by databind. May be removed from Jackson 3.0.

Returns:

Content value handler associated with this type, if any.

getContentTypeHandler

public Object getContentTypeHandler()

Internal accessor that should not be used by any code outside of jackson-databind: only used internally by databind. May be removed from Jackson 3.0.

Returns:

Content type handler associated with this type, if any.

hasValueHandler

public boolean hasValueHandler()

hasHandlers

public boolean hasHandlers()

Helper method that checks whether this type, or its (optional) key or content type has getValueHandler() or getTypeHandler(); that is, are there any non-standard handlers associated with this type object.

getGenericSignature

public String getGenericSignature()

Method for accessing signature that contains generic type information, in form compatible with JVM 1.5 as per JLS. It is a superset of getErasedSignature(), in that generic information can be automatically removed if necessary (just remove outermost angle brackets along with content inside)

getGenericSignature

public abstract StringBuilder getGenericSignature(StringBuilder sb)

Parameters:

sb - StringBuilder to append signature to

Returns:

StringBuilder that was passed in; returned to allow call chaining

getErasedSignature

public String getErasedSignature()

Method for accessing signature without generic type information, in form compatible with all versions of JVM, and specifically used for type descriptions when generating byte code.

getErasedSignature

public abstract StringBuilder getErasedSignature(StringBuilder sb)

Method for accessing signature without generic type information, in form compatible with all versions of JVM, and specifically used for type descriptions when generating byte code.

Parameters:

sb - StringBuilder to append signature to

Returns:

StringBuilder that was passed in; returned to allow call chaining

toString

public abstract String toString()

Overrides:

toString in class Object

equals

public abstract boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object