Package com.fasterxml.jackson.databind.deser.std

Class CollectionDeserializer

java.lang.Object

com.fasterxml.jackson.databind.JsonDeserializer<T>

com.fasterxml.jackson.databind.deser.std.StdDeserializer<T>

com.fasterxml.jackson.databind.deser.std.ContainerDeserializerBase<Collection<Object>>

com.fasterxml.jackson.databind.deser.std.CollectionDeserializer

All Implemented Interfaces:

ContextualDeserializer, NullValueProvider, ValueInstantiator.Gettable, Serializable

Direct Known Subclasses:

ArrayBlockingQueueDeserializer

public class CollectionDeserializer
extends ContainerDeserializerBase<Collection<Object>>
implements ContextualDeserializer

Basic serializer that can take JSON "Array" structure and construct a Collection instance, with typed contents.

Note: for untyped content (one indicated by passing Object.class as the type), UntypedObjectDeserializer is used instead. It can also construct Lists, but not with specific POJO types, only other containers and primitives/wrappers.

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CollectionDeserializer.CollectionReferringAccumulator	Helper class for dealing with Object Id references for values contained in collections being deserialized.

Nested classes/interfaces inherited from class com.fasterxml.jackson.databind.JsonDeserializer

JsonDeserializer.None

Field Summary

Fields

Modifier and Type	Field	Description
protected final JsonDeserializer<Object>	_delegateDeserializer	Deserializer that is used iff delegate-based creator is to be used for deserializing from JSON Object.
protected final JsonDeserializer<Object>	_valueDeserializer	Value deserializer.
protected final ValueInstantiator	_valueInstantiator
protected final TypeDeserializer	_valueTypeDeserializer	If element instances have polymorphic type information, this is the type deserializer that can handle it

Fields inherited from class com.fasterxml.jackson.databind.deser.std.ContainerDeserializerBase

_containerType, _nullProvider, _skipNullValues, _unwrapSingle

Fields inherited from class com.fasterxml.jackson.databind.deser.std.StdDeserializer

_valueClass, _valueType, F_MASK_ACCEPT_ARRAYS, F_MASK_INT_COERCIONS

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	CollectionDeserializer(CollectionDeserializer src)	Copy-constructor that can be used by sub-classes to allow copy-on-write styling copying of settings of an existing instance.
	CollectionDeserializer(JavaType collectionType, JsonDeserializer<Object> valueDeser, TypeDeserializer valueTypeDeser, ValueInstantiator valueInstantiator)	Constructor for context-free instances, where we do not yet know which property is using this deserializer.
protected	CollectionDeserializer(JavaType collectionType, JsonDeserializer<Object> valueDeser, TypeDeserializer valueTypeDeser, ValueInstantiator valueInstantiator, JsonDeserializer<Object> delegateDeser, NullValueProvider nuller, Boolean unwrapSingle)	Constructor used when creating contextualized instances.

Method Summary

Modifier and Type	Method	Description
protected Collection<Object>	_deserializeFromArray(JsonParser p, DeserializationContext ctxt, Collection<Object> result)
protected Collection<Object>	_deserializeFromString(JsonParser p, DeserializationContext ctxt, String value)	Logic extracted to deal with incoming String value.
protected Collection<Object>	_deserializeWithObjectId(JsonParser p, DeserializationContext ctxt, Collection<Object> result)
protected void	_tryToAddNull(JsonParser p, DeserializationContext ctxt, Collection<?> set)	java.util.TreeSet (and possibly other Collection types) does not allow addition of null values, so isolate handling here.
CollectionDeserializer	createContextual(DeserializationContext ctxt, BeanProperty property)	Method called to finalize setup of this deserializer, when it is known for which property deserializer is needed for.
protected Collection<Object>	createDefaultInstance(DeserializationContext ctxt)
Collection<Object>	deserialize(JsonParser p, DeserializationContext ctxt)	Method that can be called to ask implementation to deserialize JSON content into the value type this serializer handles.
Collection<Object>	deserialize(JsonParser p, DeserializationContext ctxt, Collection<Object> result)	Alternate deserialization method (compared to the most commonly used, JsonDeserializer.deserialize(JsonParser, DeserializationContext)), which takes in initialized value instance, to be configured and/or populated by deserializer.
Object	deserializeWithType(JsonParser p, DeserializationContext ctxt, TypeDeserializer typeDeserializer)	Base implementation that does not assume specific type inclusion mechanism.
JsonDeserializer<Object>	getContentDeserializer()	Accesor for deserializer use for deserializing content values.
ValueInstantiator	getValueInstantiator()
protected final Collection<Object>	handleNonArray(JsonParser p, DeserializationContext ctxt, Collection<Object> result)	Helper method called when current token is no START_ARRAY.
boolean	isCachable()	Method called to see if deserializer instance is cachable and usable for other properties of same type (type for which instance was created).
LogicalType	logicalType()	Method for accessing logical type of values this deserializer produces.
protected CollectionDeserializer	withResolved(JsonDeserializer<?> dd, JsonDeserializer<?> vd, TypeDeserializer vtd, NullValueProvider nuller, Boolean unwrapSingle)	Fluent-factory method call to construct contextual instance.

Methods inherited from class com.fasterxml.jackson.databind.deser.std.ContainerDeserializerBase

findBackReference, getContentType, getEmptyAccessPattern, getEmptyValue, getValueType, supportsUpdate, wrapAndThrow, wrapAndThrow

Methods inherited from class com.fasterxml.jackson.databind.deser.std.StdDeserializer

_byteOverflow, _checkBooleanToStringCoercion, _checkCoercionFail, _checkDoubleSpecialValue, _checkFloatSpecialValue, _checkFloatToIntCoercion, _checkFloatToStringCoercion, _checkFromStringCoercion, _checkFromStringCoercion, _checkIntToFloatCoercion, _checkIntToStringCoercion, _checkTextualNull, _checkToStringCoercion, _coerceBooleanFromInt, _coercedTypeDesc, _coercedTypeDesc, _coerceEmptyString, _coerceIntegral, _coerceNullToken, _coerceTextualNull, _deserializeFromArray, _deserializeFromEmpty, _deserializeFromEmptyString, _deserializeFromString, _deserializeWrappedValue, _failDoubleToIntCoercion, _findCoercionFromBlankString, _findCoercionFromEmptyArray, _findCoercionFromEmptyString, _findNullProvider, _hasTextualNull, _intOverflow, _isBlank, _isEmptyOrTextualNull, _isFalse, _isIntNumber, _isNaN, _isNegInf, _isPosInf, _isTrue, _neitherNull, _nonNullNumber, _parseBoolean, _parseBooleanFromInt, _parseBooleanPrimitive, _parseBooleanPrimitive, _parseBytePrimitive, _parseDate, _parseDate, _parseDateFromArray, _parseDouble, _parseDouble, _parseDoublePrimitive, _parseDoublePrimitive, _parseDoublePrimitive, _parseFloatPrimitive, _parseFloatPrimitive, _parseFloatPrimitive, _parseInteger, _parseInteger, _parseIntPrimitive, _parseIntPrimitive, _parseLong, _parseLong, _parseLongPrimitive, _parseLongPrimitive, _parseShortPrimitive, _parseString, _parseString, _reportFailedNullCoerce, _shortOverflow, _verifyEndArrayForSingle, _verifyNullForPrimitive, _verifyNullForPrimitiveCoercion, _verifyNullForScalarCoercion, _verifyNumberForScalarCoercion, _verifyStringForScalarCoercion, findContentNullProvider, findContentNullStyle, findConvertingContentDeserializer, findDeserializer, findFormatFeature, findFormatOverrides, findValueNullProvider, getValueClass, getValueType, handledType, handleMissingEndArrayForSingle, handleNestedArrayForSingle, handleUnknownProperty, isDefaultDeserializer, isDefaultKeyDeserializer

Methods inherited from class com.fasterxml.jackson.databind.JsonDeserializer

deserializeWithType, getAbsentValue, getDelegatee, getEmptyValue, getKnownPropertyNames, getNullAccessPattern, getNullValue, getNullValue, getObjectIdReader, replaceDelegatee, unwrappingDeserializer

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

_valueDeserializer

protected final JsonDeserializer<Object> _valueDeserializer

Value deserializer.

_valueTypeDeserializer

protected final TypeDeserializer _valueTypeDeserializer

If element instances have polymorphic type information, this is the type deserializer that can handle it

_valueInstantiator

protected final ValueInstantiator _valueInstantiator

_delegateDeserializer

protected final JsonDeserializer<Object> _delegateDeserializer

Deserializer that is used iff delegate-based creator is to be used for deserializing from JSON Object.

Constructor Details

CollectionDeserializer

public CollectionDeserializer(JavaType collectionType,
 JsonDeserializer<Object> valueDeser,
 TypeDeserializer valueTypeDeser,
 ValueInstantiator valueInstantiator)

Constructor for context-free instances, where we do not yet know which property is using this deserializer.

CollectionDeserializer

protected CollectionDeserializer(JavaType collectionType,
 JsonDeserializer<Object> valueDeser,
 TypeDeserializer valueTypeDeser,
 ValueInstantiator valueInstantiator,
 JsonDeserializer<Object> delegateDeser,
 NullValueProvider nuller,
 Boolean unwrapSingle)

Constructor used when creating contextualized instances.

Since:

2.9

CollectionDeserializer

protected CollectionDeserializer(CollectionDeserializer src)

Copy-constructor that can be used by sub-classes to allow copy-on-write styling copying of settings of an existing instance.

Method Details

withResolved

protected CollectionDeserializer withResolved(JsonDeserializer<?> dd,
 JsonDeserializer<?> vd,
 TypeDeserializer vtd,
 NullValueProvider nuller,
 Boolean unwrapSingle)

Fluent-factory method call to construct contextual instance.

Since:

2.9

isCachable

public boolean isCachable()

Description copied from class: JsonDeserializer

Method called to see if deserializer instance is cachable and usable for other properties of same type (type for which instance was created).

Note that cached instances are still resolved on per-property basis, if instance implements ResolvableDeserializer: cached instance is just as the base. This means that in most cases it is safe to cache instances; however, it only makes sense to cache instances if instantiation is expensive, or if instances are heavy-weight.

Default implementation returns false, to indicate that no caching is done.

Overrides:

isCachable in class JsonDeserializer<Collection<Object>>

logicalType

public LogicalType logicalType()

Description copied from class: JsonDeserializer

Method for accessing logical type of values this deserializer produces. Typically used for further configuring handling of values, for example, to find which coercions are legal.

Overrides:

logicalType in class JsonDeserializer<Collection<Object>>

Returns:

Logical type of values this deserializer produces, if known; null if not

createContextual

public CollectionDeserializer createContextual(DeserializationContext ctxt,
 BeanProperty property)
                                        throws JsonMappingException

Method called to finalize setup of this deserializer, when it is known for which property deserializer is needed for.

Specified by:

createContextual in interface ContextualDeserializer

Parameters:

ctxt - Deserialization context to access configuration, additional deserializers that may be needed by this deserializer

property - Method, field or constructor parameter that represents the property (and is used to assign deserialized value). Should be available; but there may be cases where caller cannot provide it and null is passed instead (in which case impls usually pass 'this' deserializer as is)

Returns:

Deserializer to use for deserializing values of specified property; may be this instance or a new instance.

Throws:

JsonMappingException

getContentDeserializer

public JsonDeserializer<Object> getContentDeserializer()

Description copied from class: ContainerDeserializerBase

Accesor for deserializer use for deserializing content values.

Specified by:

getContentDeserializer in class ContainerDeserializerBase<Collection<Object>>

getValueInstantiator

public ValueInstantiator getValueInstantiator()

Specified by:

getValueInstantiator in interface ValueInstantiator.Gettable

Overrides:

getValueInstantiator in class StdDeserializer<Collection<Object>>

deserialize

public Collection<Object> deserialize(JsonParser p,
 DeserializationContext ctxt)
                               throws IOException

Description copied from class: JsonDeserializer

Method that can be called to ask implementation to deserialize JSON content into the value type this serializer handles. Returned instance is to be constructed by method itself.

Pre-condition for this method is that the parser points to the first event that is part of value to deserializer (and which is never JSON 'null' literal, more on this below): for simple types it may be the only value; and for structured types the Object start marker or a FIELD_NAME.

The two possible input conditions for structured types result from polymorphism via fields. In the ordinary case, Jackson calls this method when it has encountered an OBJECT_START, and the method implementation must advance to the next token to see the first field name. If the application configures polymorphism via a field, then the object looks like the following.

      {
          "@class": "class name",
          ...
      }
  

Jackson consumes the two tokens (the @class field name and its value) in order to learn the class and select the deserializer. Thus, the stream is pointing to the FIELD_NAME for the first field after the @class. Thus, if you want your method to work correctly both with and without polymorphism, you must begin your method with:

       if (p.currentToken() == JsonToken.START_OBJECT) {
         p.nextToken();
       }
  

This results in the stream pointing to the field name, so that the two conditions align.

Post-condition is that the parser will point to the last event that is part of deserialized value (or in case deserialization fails, event that was not recognized or usable, which may be the same event as the one it pointed to upon call).

Handling null values (JsonToken.VALUE_NULL)
: Note that this method is never called for the JSON null literal to avoid every deserializer from having to handle null values. Instead, the JsonDeserializer.getNullValue(DeserializationContext) method is called to produce a null value. To influence null handling, custom deserializers should override JsonDeserializer.getNullValue(DeserializationContext) and usually also JsonDeserializer.getNullAccessPattern().

Specified by:

deserialize in class JsonDeserializer<Collection<Object>>

Parameters:

p - Parser used for reading JSON content

ctxt - Context that can be used to access information about this deserialization activity.

Returns:

Deserialized value

Throws:

IOException

createDefaultInstance

protected Collection<Object> createDefaultInstance(DeserializationContext ctxt)
                                            throws IOException

Throws:

IOException

Since:

2.9

deserialize

public Collection<Object> deserialize(JsonParser p,
 DeserializationContext ctxt,
 Collection<Object> result)
                               throws IOException

Description copied from class: JsonDeserializer

Alternate deserialization method (compared to the most commonly used, JsonDeserializer.deserialize(JsonParser, DeserializationContext)), which takes in initialized value instance, to be configured and/or populated by deserializer. Method is not necessarily used (or supported) by all types (it will not work for immutable types, for obvious reasons): most commonly it is used for Collections and Maps. It may be used both with "updating readers" (for POJOs) and when Collections and Maps use "getter as setter".

Default implementation just throws UnsupportedOperationException, to indicate that types that do not explicitly add support do not necessarily support update-existing-value operation (esp. immutable types)

Overrides:

deserialize in class JsonDeserializer<Collection<Object>>

Throws:

IOException

deserializeWithType

public Object deserializeWithType(JsonParser p,
 DeserializationContext ctxt,
 TypeDeserializer typeDeserializer)
                           throws IOException

Description copied from class: StdDeserializer

Base implementation that does not assume specific type inclusion mechanism. Sub-classes are expected to override this method if they are to handle type information.

Overrides:

deserializeWithType in class StdDeserializer<Collection<Object>>

typeDeserializer - Deserializer to use for handling type information

Throws:

IOException

_deserializeFromString

protected Collection<Object> _deserializeFromString(JsonParser p,
 DeserializationContext ctxt,
 String value)
                                             throws IOException

Logic extracted to deal with incoming String value.

Throws:

IOException

Since:

2.12

_deserializeFromArray

protected Collection<Object> _deserializeFromArray(JsonParser p,
 DeserializationContext ctxt,
 Collection<Object> result)
                                            throws IOException

Throws:

IOException

Since:

2.12

handleNonArray

protected final Collection<Object> handleNonArray(JsonParser p,
 DeserializationContext ctxt,
 Collection<Object> result)
                                           throws IOException

Helper method called when current token is no START_ARRAY. Will either throw an exception, or try to handle value as if member of implicit array, depending on configuration.

Throws:

IOException

_deserializeWithObjectId

protected Collection<Object> _deserializeWithObjectId(JsonParser p,
 DeserializationContext ctxt,
 Collection<Object> result)
                                               throws IOException

Throws:

IOException

_tryToAddNull

protected void _tryToAddNull(JsonParser p,
 DeserializationContext ctxt,
 Collection<?> set)
                      throws IOException

java.util.TreeSet (and possibly other Collection types) does not allow addition of null values, so isolate handling here.

Throws:

IOException

Since:

2.17