Package com.fasterxml.jackson.databind.jsontype

Class TypeDeserializer

  • Direct Known Subclasses:
    TypeDeserializerBase
    public abstract class TypeDeserializer
extends java.lang.Object
    Interface for deserializing type information from JSON content, to type-safely deserialize data into correct polymorphic instance (when type inclusion has been enabled for type handled).

    Separate deserialization methods are needed because serialized form for inclusion mechanism JsonTypeInfo.As.PROPERTY is slighty different if value is not expressed as JSON Object: and as such both type deserializer and serializer need to JSON Object form (array, object or other (== scalar)) being used.

    • Constructor Detail

      • TypeDeserializer

        public TypeDeserializer()

    • Method Detail

      • forProperty

        public abstract TypeDeserializer forProperty​(BeanProperty prop)
        Method called to create contextual version, to be used for values of given property. This may be the type itself (as is the case for bean properties), or values contained (for Collection or Map valued properties).

      • getTypeInclusion

        public abstract JsonTypeInfo.As getTypeInclusion()
        Accessor for type information inclusion method that deserializer uses; indicates how type information is (expected to be) embedded in JSON input.

      • getPropertyName

        public abstract java.lang.String getPropertyName()
        Name of property that contains type information, if property-based inclusion is used.

      • getTypeIdResolver

        public abstract TypeIdResolver getTypeIdResolver()
        Accessor for object that handles conversions between types and matching type ids.

      • getDefaultImpl

        public abstract java.lang.Class<?> getDefaultImpl()
        Accessor for "default implementation" type; optionally defined class to use in cases where type id is not accessible for some reason (either missing, or cannot be resolved)

      • hasDefaultImpl

        public boolean hasDefaultImpl()
        Since:
        2.12

      • deserializeTypedFromObject

        public abstract java.lang.Object deserializeTypedFromObject​(JsonParser p,
                                                            DeserializationContext ctxt)
                                                     throws java.io.IOException
        Method called to let this type deserializer handle deserialization of "typed" object, when value itself is serialized as JSON Object (regardless of Java type). Method needs to figure out intended polymorphic type, locate JsonDeserializer to use, and call it with JSON data to deserializer (which does not contain type information).
        Throws:
        java.io.IOException

      • deserializeTypedFromArray

        public abstract java.lang.Object deserializeTypedFromArray​(JsonParser p,
                                                           DeserializationContext ctxt)
                                                    throws java.io.IOException
        Method called to let this type deserializer handle deserialization of "typed" object, when value itself is serialized as JSON Array (regardless of Java type). Method needs to figure out intended polymorphic type, locate JsonDeserializer to use, and call it with JSON data to deserializer (which does not contain type information).
        Throws:
        java.io.IOException

      • deserializeTypedFromScalar

        public abstract java.lang.Object deserializeTypedFromScalar​(JsonParser p,
                                                            DeserializationContext ctxt)
                                                     throws java.io.IOException
        Method called to let this type deserializer handle deserialization of "typed" object, when value itself is serialized as a scalar JSON value (something other than Array or Object), regardless of Java type. Method needs to figure out intended polymorphic type, locate JsonDeserializer to use, and call it with JSON data to deserializer (which does not contain type information).
        Throws:
        java.io.IOException

      • deserializeTypedFromAny

        public abstract java.lang.Object deserializeTypedFromAny​(JsonParser p,
                                                         DeserializationContext ctxt)
                                                  throws java.io.IOException
        Method called to let this type deserializer handle deserialization of "typed" object, when value itself may have been serialized using any kind of JSON value (Array, Object, scalar). Should only be called if JSON serialization is polymorphic (not Java type); for example when using JSON node representation, or "untyped" Java object (which may be Map, Collection, wrapper/primitive etc).
        Throws:
        java.io.IOException

      • deserializeIfNatural

        public static java.lang.Object deserializeIfNatural​(JsonParser p,
                                                    DeserializationContext ctxt,
                                                    JavaType baseType)
                                             throws java.io.IOException
        Helper method used to check if given parser might be pointing to a "natural" value, and one that would be acceptable as the result value (compatible with declared base type)
        Throws:
        java.io.IOException

      • deserializeIfNatural

        public static java.lang.Object deserializeIfNatural​(JsonParser p,
                                                    DeserializationContext ctxt,
                                                    java.lang.Class<?> base)
                                             throws java.io.IOException
        Throws:
        java.io.IOException