package com.fasterxml.jackson.databind.module;

import java.util.*;

import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.Deserializers;
import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
import com.fasterxml.jackson.databind.type.*;

Simple implementation Deserializers which allows registration of deserializers based on raw (type erased class). It can work well for basic bean and scalar type deserializers, but is not a good fit for handling generic types (like Maps and Collections or array types).

Unlike SimpleSerializers, this class does not currently support generic mappings; all mappings must be to exact declared deserialization type.

/** * Simple implementation {@link Deserializers} which allows registration of * deserializers based on raw (type erased class). * It can work well for basic bean and scalar type deserializers, but is not * a good fit for handling generic types (like {@link Map}s and {@link Collection}s * or array types). *<p> * Unlike {@link SimpleSerializers}, this class does not currently support generic mappings; * all mappings must be to exact declared deserialization type. */
public class SimpleDeserializers extends Deserializers.Base implements java.io.Serializable { private static final long serialVersionUID = 1L; protected HashMap<ClassKey,JsonDeserializer<?>> _classMappings = null;
Flag to help find "generic" enum deserializer, if one has been registered.
Since:2.3
/** * Flag to help find "generic" enum deserializer, if one has been registered. * * @since 2.3 */
protected boolean _hasEnumDeserializer = false; /* /********************************************************** /* Life-cycle, construction and configuring /********************************************************** */ public SimpleDeserializers() { }
Since:2.1
/** * @since 2.1 */
public SimpleDeserializers(Map<Class<?>,JsonDeserializer<?>> desers) { addDeserializers(desers); } public <T> void addDeserializer(Class<T> forClass, JsonDeserializer<? extends T> deser) { ClassKey key = new ClassKey(forClass); if (_classMappings == null) { _classMappings = new HashMap<ClassKey,JsonDeserializer<?>>(); } _classMappings.put(key, deser); // [Issue#227]: generic Enum deserializer? if (forClass == Enum.class) { _hasEnumDeserializer = true; } }
Since:2.1
/** * @since 2.1 */
@SuppressWarnings("unchecked") public void addDeserializers(Map<Class<?>,JsonDeserializer<?>> desers) { for (Map.Entry<Class<?>,JsonDeserializer<?>> entry : desers.entrySet()) { Class<?> cls = entry.getKey(); // what a mess... nominal generics safety... JsonDeserializer<Object> deser = (JsonDeserializer<Object>) entry.getValue(); addDeserializer((Class<Object>) cls, deser); } } /* /********************************************************** /* Serializers implementation /********************************************************** */ @Override public JsonDeserializer<?> findArrayDeserializer(ArrayType type, DeserializationConfig config, BeanDescription beanDesc, TypeDeserializer elementTypeDeserializer, JsonDeserializer<?> elementDeserializer) throws JsonMappingException { return _find(type); } @Override public JsonDeserializer<?> findBeanDeserializer(JavaType type, DeserializationConfig config, BeanDescription beanDesc) throws JsonMappingException { return _find(type); } @Override public JsonDeserializer<?> findCollectionDeserializer(CollectionType type, DeserializationConfig config, BeanDescription beanDesc, TypeDeserializer elementTypeDeserializer, JsonDeserializer<?> elementDeserializer) throws JsonMappingException { return _find(type); } @Override public JsonDeserializer<?> findCollectionLikeDeserializer(CollectionLikeType type, DeserializationConfig config, BeanDescription beanDesc, TypeDeserializer elementTypeDeserializer, JsonDeserializer<?> elementDeserializer) throws JsonMappingException { return _find(type); } @Override public JsonDeserializer<?> findEnumDeserializer(Class<?> type, DeserializationConfig config, BeanDescription beanDesc) throws JsonMappingException { if (_classMappings == null) { return null; } JsonDeserializer<?> deser = _classMappings.get(new ClassKey(type)); if (deser == null) { // 29-Sep-2019, tatu: Not 100% sure this is workable logic but leaving // as is (wrt [databind#2457]. Probably works ok since this covers direct // sub-classes of `Enum`; but even if custom sub-classes aren't, unlikely // mapping for those ever requested for deserialization if (_hasEnumDeserializer && type.isEnum()) { deser = _classMappings.get(new ClassKey(Enum.class)); } } return deser; } @Override public JsonDeserializer<?> findTreeNodeDeserializer(Class<? extends JsonNode> nodeType, DeserializationConfig config, BeanDescription beanDesc) throws JsonMappingException { if (_classMappings == null) { return null; } return _classMappings.get(new ClassKey(nodeType)); } @Override public JsonDeserializer<?> findReferenceDeserializer(ReferenceType refType, DeserializationConfig config, BeanDescription beanDesc, TypeDeserializer contentTypeDeserializer, JsonDeserializer<?> contentDeserializer) throws JsonMappingException { // 21-Oct-2015, tatu: Unlikely this will really get used (reference types need more // work, simple registration probably not sufficient). But whatever. return _find(refType); } @Override public JsonDeserializer<?> findMapDeserializer(MapType type, DeserializationConfig config, BeanDescription beanDesc, KeyDeserializer keyDeserializer, TypeDeserializer elementTypeDeserializer, JsonDeserializer<?> elementDeserializer) throws JsonMappingException { return _find(type); } @Override public JsonDeserializer<?> findMapLikeDeserializer(MapLikeType type, DeserializationConfig config, BeanDescription beanDesc, KeyDeserializer keyDeserializer, TypeDeserializer elementTypeDeserializer, JsonDeserializer<?> elementDeserializer) throws JsonMappingException { return _find(type); } @Override // since 2.11 public boolean hasDeserializerFor(DeserializationConfig config, Class<?> valueType) { return (_classMappings != null) && _classMappings.containsKey(new ClassKey(valueType)); } private final JsonDeserializer<?> _find(JavaType type) { if (_classMappings == null) { return null; } return _classMappings.get(new ClassKey(type.getRawClass())); } }