public class StringDeserializer extends StdScalarDeserializer<String>
JsonDeserializer.None| Modifier and Type | Field and Description |
|---|---|
static StringDeserializer |
instance |
_valueClass, F_MASK_ACCEPT_ARRAYS, F_MASK_INT_COERCIONS| Constructor and Description |
|---|
StringDeserializer() |
| Modifier and Type | Method and Description |
|---|---|
String |
deserialize(JsonParser p,
DeserializationContext ctxt)
Method that can be called to ask implementation to deserialize
JSON content into the value type this serializer handles.
|
String |
deserializeWithType(JsonParser p,
DeserializationContext ctxt,
TypeDeserializer typeDeserializer)
Base implementation that does not assume specific type
inclusion mechanism.
|
Object |
getEmptyValue(DeserializationContext ctxt)
Method called to determine value to be used for "empty" values
(most commonly when deserializing from empty JSON Strings).
|
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).
|
deserialize, getEmptyAccessPattern, getNullAccessPattern, supportsUpdate_byteOverflow, _coercedTypeDesc, _coerceEmptyString, _coerceIntegral, _coerceNullToken, _coerceTextualNull, _deserializeFromArray, _deserializeFromEmpty, _deserializeWrappedValue, _failDoubleToIntCoercion, _findNullProvider, _hasTextualNull, _intOverflow, _isEmptyOrTextualNull, _isIntNumber, _isNaN, _isNegInf, _isPosInf, _neitherNull, _nonNullNumber, _parseBooleanFromInt, _parseBooleanPrimitive, _parseBytePrimitive, _parseDate, _parseDate, _parseDateFromArray, _parseDoublePrimitive, _parseDoublePrimitive, _parseFloatPrimitive, _parseFloatPrimitive, _parseIntPrimitive, _parseIntPrimitive, _parseLongPrimitive, _parseLongPrimitive, _parseShortPrimitive, _parseString, _reportFailedNullCoerce, _shortOverflow, _verifyEndArrayForSingle, _verifyNullForPrimitive, _verifyNullForPrimitiveCoercion, _verifyNullForScalarCoercion, _verifyNumberForScalarCoercion, _verifyStringForScalarCoercion, findContentNullProvider, findContentNullStyle, findConvertingContentDeserializer, findDeserializer, findFormatFeature, findFormatOverrides, findValueNullProvider, getValueClass, getValueType, handledType, handleMissingEndArrayForSingle, handleUnknownProperty, isDefaultDeserializer, isDefaultKeyDeserializer, parseDoublefindBackReference, getDelegatee, getEmptyValue, getKnownPropertyNames, getNullValue, getNullValue, getObjectIdReader, replaceDelegatee, unwrappingDeserializerpublic static final StringDeserializer instance
public boolean isCachable()
JsonDeserializer
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.
isCachable in class JsonDeserializer<String>public Object getEmptyValue(DeserializationContext ctxt) throws JsonMappingException
JsonDeserializerJsonDeserializer.getNullValue(com.fasterxml.jackson.databind.DeserializationContext) (which in turn
is usually simply Java null), but it can be overridden
for types. Or, if type should never be converted from empty
String, method can also throw an exception.
Since version 2.6 (in which the context argument was added), call is expected to be made each and every time an empty value is needed.
Since version 2.9 does not require return of `T` any more.
Default implementation simply calls JsonDeserializer.getNullValue(com.fasterxml.jackson.databind.DeserializationContext) and
returns value.
getEmptyValue in class JsonDeserializer<String>JsonMappingExceptionpublic String deserialize(JsonParser p, DeserializationContext ctxt) throws IOException
JsonDeserializerPre-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.getCurrentToken() == 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).
Note that this method is never called for JSON null literal, and thus deserializers need (and should) not check for it.
deserialize in class JsonDeserializer<String>p - Parsed used for reading JSON contentctxt - Context that can be used to access information about
this deserialization activity.IOExceptionpublic String deserializeWithType(JsonParser p, DeserializationContext ctxt, TypeDeserializer typeDeserializer) throws IOException
StdDeserializerdeserializeWithType in class StdScalarDeserializer<String>typeDeserializer - Deserializer to use for handling type informationIOExceptionCopyright © 2008–2018 FasterXML. All rights reserved.