com.fasterxml.jackson.databind
Class JavaType

java.lang.Object
  com.fasterxml.jackson.core.type.ResolvedType
      com.fasterxml.jackson.databind.JavaType

Direct Known Subclasses:

TypeBase

public abstract class JavaType
extends com.fasterxml.jackson.core.type.ResolvedType

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

Instances can (only) be constructed by com.fasterxml.jackson.databind.TypeFactory (included in "jackson-databind")

Field Summary

protected 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 int	_hashCode
protected Object	_typeHandler Optional handler that can be attached to indicate how to handle additional type metadata associated with this type.
protected 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

protected

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

Method Summary

protected void	_assertSubclass(Class<?> subclass, Class<?> superClass)
protected abstract JavaType	_narrow(Class<?> subclass)
protected JavaType	_widen(Class<?> superclass) Default implementation is just to call _narrow(java.lang.Class), since underlying type construction is usually identical
JavaType	containedType(int index)
int	containedTypeCount()
String	containedTypeName(int index)
abstract boolean	equals(Object o)
JavaType	forcedNarrowBy(Class<?> subclass) More efficient version of narrowBy(java.lang.Class), called by internal framework in cases where compatibility checks are to be skipped.
JavaType	getContentType()
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)
JavaType	getKeyType()
Class<?>	getRawClass()
<T> T	getTypeHandler() Method for accessing type handler associated with this type, if any
<T> T	getValueHandler() Method for accessing value handler associated with this type, if any
boolean	hasGenericTypes()
int	hashCode()
boolean	hasRawClass(Class<?> clz) Method that can be used to check whether this type has specified Class as its type erasure.
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()
boolean	isEnumType()
boolean	isFinal()
boolean	isInterface()
boolean	isMapLikeType()
boolean	isPrimitive()
boolean	isThrowable()
JavaType	narrowBy(Class<?> subclass) Method that can be called to do a "narrowing" conversions; that is, to return a type with a raw class that is assignable to the raw class of this type.
abstract JavaType	narrowContentsBy(Class<?> contentClass)
abstract String	toString()
JavaType	widenBy(Class<?> superclass) Method that can be called to do a "widening" conversions; that is, to return a type with a raw class that could be assigned from this type.
abstract JavaType	widenContentsBy(Class<?> contentClass)
abstract JavaType	withContentTypeHandler(Object h) "Copy method" that will construct a new instance that is identical to this instance, except that its content type will have specified type handler assigned.
abstract JavaType	withContentValueHandler(Object h) "Copy method" that will construct a new instance that is identical to this instance, except that it will have specified content value handler assigned.
abstract JavaType	withTypeHandler(Object h) "Copy method" that will construct a new instance that is identical to this instance, except that it will have specified type handler assigned.
abstract JavaType	withValueHandler(Object h) "Copy method" that will construct a new instance that is identical to this instance, except that it will have specified value handler assigned.

Methods inherited from class com.fasterxml.jackson.core.type.ResolvedType

toCanonical

Methods inherited from class java.lang.Object

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

Field Detail

_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.

_hashCode

protected final int _hashCode

_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.

Constructor Detail

JavaType

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

Parameters:

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

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

Method Detail

withTypeHandler

public abstract JavaType withTypeHandler(Object h)

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

Returns:

Newly created type instance

withContentTypeHandler

public abstract JavaType withContentTypeHandler(Object h)

"Copy method" that will construct a new instance that is identical to this instance, except that its content type will have specified type handler assigned.

Returns:

Newly created type instance

withValueHandler

public abstract JavaType withValueHandler(Object h)

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

Returns:

Newly created type instance

withContentValueHandler

public abstract JavaType withContentValueHandler(Object h)

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

Returns:

Newly created type instance

narrowBy

public JavaType narrowBy(Class<?> subclass)

Method that can be called to do a "narrowing" conversions; that is, to return a type with a raw class that is assignable to the raw class of this type. If this is not possible, an IllegalArgumentException is thrown. If class is same as the current raw class, instance itself is returned.

forcedNarrowBy

public JavaType forcedNarrowBy(Class<?> subclass)

More efficient version of narrowBy(java.lang.Class), called by internal framework in cases where compatibility checks are to be skipped.

widenBy

public JavaType widenBy(Class<?> superclass)

Method that can be called to do a "widening" conversions; that is, to return a type with a raw class that could be assigned from this type. If such conversion is not possible, an IllegalArgumentException is thrown. If class is same as the current raw class, instance itself is returned.

_narrow

protected abstract JavaType _narrow(Class<?> subclass)

_widen

protected JavaType _widen(Class<?> superclass)

Default implementation is just to call _narrow(java.lang.Class), since underlying type construction is usually identical

narrowContentsBy

public abstract JavaType narrowContentsBy(Class<?> contentClass)

widenContentsBy

public abstract JavaType widenContentsBy(Class<?> contentClass)

getRawClass

public final Class<?> getRawClass()

Specified by:

getRawClass in class com.fasterxml.jackson.core.type.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 com.fasterxml.jackson.core.type.ResolvedType

isAbstract

public boolean isAbstract()

Specified by:

isAbstract in class com.fasterxml.jackson.core.type.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 com.fasterxml.jackson.core.type.ResolvedType

isThrowable

public boolean isThrowable()

Specified by:

isThrowable in class com.fasterxml.jackson.core.type.ResolvedType

isArrayType

public boolean isArrayType()

Specified by:

isArrayType in class com.fasterxml.jackson.core.type.ResolvedType

isEnumType

public final boolean isEnumType()

Specified by:

isEnumType in class com.fasterxml.jackson.core.type.ResolvedType

isInterface

public final boolean isInterface()

Specified by:

isInterface in class com.fasterxml.jackson.core.type.ResolvedType

isPrimitive

public final boolean isPrimitive()

Specified by:

isPrimitive in class com.fasterxml.jackson.core.type.ResolvedType

isFinal

public final boolean isFinal()

Specified by:

isFinal in class com.fasterxml.jackson.core.type.ResolvedType

isContainerType

public abstract boolean isContainerType()

Specified by:

isContainerType in class com.fasterxml.jackson.core.type.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 com.fasterxml.jackson.core.type.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 com.fasterxml.jackson.core.type.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)

hasGenericTypes

public boolean hasGenericTypes()

Specified by:

hasGenericTypes in class com.fasterxml.jackson.core.type.ResolvedType

getKeyType

public JavaType getKeyType()

Specified by:

getKeyType in class com.fasterxml.jackson.core.type.ResolvedType

getContentType

public JavaType getContentType()

Specified by:

getContentType in class com.fasterxml.jackson.core.type.ResolvedType

containedTypeCount

public int containedTypeCount()

Specified by:

containedTypeCount in class com.fasterxml.jackson.core.type.ResolvedType

containedType

public JavaType containedType(int index)

Specified by:

containedType in class com.fasterxml.jackson.core.type.ResolvedType

containedTypeName

public String containedTypeName(int index)

Specified by:

containedTypeName in class com.fasterxml.jackson.core.type.ResolvedType

getValueHandler

public <T> T getValueHandler()

Method for accessing value handler associated with this type, if any

getTypeHandler

public <T> T getTypeHandler()

Method for accessing type handler associated with this type, if any

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

_assertSubclass

protected void _assertSubclass(Class<?> subclass,
                               Class<?> superClass)

toString

public abstract String toString()

Overrides:

toString in class Object

equals

public abstract boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public final int hashCode()

Overrides:

hashCode in class Object