Package com.fasterxml.jackson.databind.annotation

Annotation Type JsonDeserialize

@Target({ANNOTATION_TYPE,METHOD,FIELD,TYPE,PARAMETER})
@Retention(RUNTIME)
public @interface JsonDeserialize

Annotation use for configuring deserialization aspects, by attaching to "setter" methods or fields, or to value classes. When annotating value classes, configuration is used for instances of the value class but can be overridden by more specific annotations (ones that attach to methods or fields).

An example annotation would be:

  @JsonDeserialize(using=MySerializer.class,
    as=MyHashMap.class,
    keyAs=MyHashKey.class,
    contentAs=MyHashValue.class
  )

Something to note on usage:

• All other annotations regarding behavior during building should be on Builder class and NOT on target POJO class: for example @JsonIgnoreProperties should be on Builder to prevent "unknown property" errors.
• Similarly configuration overrides (see ObjectMapper.configOverride(java.lang.Class<?>)) should be targeted at Builder class, not target POJO class.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element	Description
java.lang.Class<?>	as	Concrete type to deserialize values as, instead of type otherwise declared.
java.lang.Class<?>	builder	Annotation for specifying if an external Builder class is to be used for building up deserialized instances of annotated class.
java.lang.Class<?>	contentAs	Concrete type to deserialize content (elements of a Collection/array, values of Maps) values as, instead of type otherwise declared.
java.lang.Class<? extends Converter>	contentConverter	Similar to converter(), but used for values of structures types (List, arrays, Maps).
java.lang.Class<? extends JsonDeserializer>	contentUsing	Deserializer class to use for deserializing contents (elements of a Collection/array, values of Maps) of annotated property.
java.lang.Class<? extends Converter>	converter	Which helper object (if any) is to be used to convert from Jackson-bound intermediate type (source type of converter) into actual property type (which must be same as result type of converter).
java.lang.Class<?>	keyAs	Concrete type to deserialize keys of Map as, instead of type otherwise declared.
java.lang.Class<? extends KeyDeserializer>	keyUsing	Deserializer class to use for deserializing Map keys of annotated property.
java.lang.Class<? extends JsonDeserializer>	using	Deserializer class to use for deserializing associated value.

Element Detail

using

java.lang.Class<? extends JsonDeserializer> using

Deserializer class to use for deserializing associated value. Depending on what is annotated, value is either an instance of annotated class (used globablly anywhere where class deserializer is needed); or only used for deserializing property access via a setter method.

Default:

com.fasterxml.jackson.databind.JsonDeserializer.None.class

contentUsing

java.lang.Class<? extends JsonDeserializer> contentUsing

Deserializer class to use for deserializing contents (elements of a Collection/array, values of Maps) of annotated property. Can only be used on instances (methods, fields, constructors), and not value classes themselves.

Default:

com.fasterxml.jackson.databind.JsonDeserializer.None.class

keyUsing

java.lang.Class<? extends KeyDeserializer> keyUsing

Deserializer class to use for deserializing Map keys of annotated property. Can only be used on instances (methods, fields, constructors), and not value classes themselves.

Default:

com.fasterxml.jackson.databind.KeyDeserializer.None.class

builder

java.lang.Class<?> builder

Annotation for specifying if an external Builder class is to be used for building up deserialized instances of annotated class. If so, an instance of referenced class is first constructed (possibly using a Creator method; or if none defined, using default constructor), and its "with-methods" are used for populating fields; and finally "build-method" is invoked to complete deserialization.

Default:

java.lang.Void.class

converter

java.lang.Class<? extends Converter> converter

Which helper object (if any) is to be used to convert from Jackson-bound intermediate type (source type of converter) into actual property type (which must be same as result type of converter). This is often used for two-step deserialization; Jackson binds data into suitable intermediate type (like Tree representation), and converter then builds actual property type.

Since:

2.2

Default:

com.fasterxml.jackson.databind.util.Converter.None.class

contentConverter

java.lang.Class<? extends Converter> contentConverter

Similar to converter(), but used for values of structures types (List, arrays, Maps).

Since:

2.2

Default:

com.fasterxml.jackson.databind.util.Converter.None.class

as

java.lang.Class<?> as

Concrete type to deserialize values as, instead of type otherwise declared. Must be a subtype of declared type; otherwise an exception may be thrown by deserializer.

Bogus type Void can be used to indicate that declared type is used as is (i.e. this annotation property has no setting); this since annotation properties are not allowed to have null value.

Note: if using() is also used it has precedence (since it directly specified deserializer, whereas this would only be used to locate the deserializer) and value of this annotation property is ignored.

Default:

java.lang.Void.class

keyAs

java.lang.Class<?> keyAs

Concrete type to deserialize keys of Map as, instead of type otherwise declared. Must be a subtype of declared type; otherwise an exception may be thrown by deserializer.

Default:

java.lang.Void.class

contentAs

java.lang.Class<?> contentAs

Concrete type to deserialize content (elements of a Collection/array, values of Maps) values as, instead of type otherwise declared. Must be a subtype of declared type; otherwise an exception may be thrown by deserializer.

Default:

java.lang.Void.class