package com.fasterxml.jackson.databind.module;

import java.util.*;


import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
import com.fasterxml.jackson.databind.ser.Serializers;
import com.fasterxml.jackson.databind.type.ArrayType;
import com.fasterxml.jackson.databind.type.ClassKey;
import com.fasterxml.jackson.databind.type.CollectionLikeType;
import com.fasterxml.jackson.databind.type.CollectionType;
import com.fasterxml.jackson.databind.type.MapLikeType;
import com.fasterxml.jackson.databind.type.MapType;

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

Type registrations are assumed to be general; meaning that registration of serializer for a super type will also be used for handling subtypes, unless an exact match is found first. As an example, handler for CharSequence would also be used serializing StringBuilder instances, unless a direct mapping was found.

/** * Simple implementation {@link Serializers} which allows registration of * serializers based on raw (type erased class). * It can work well for basic bean and scalar type serializers, but is not * a good fit for handling generic types (like {@link Map}s and {@link Collection}s). *<p> * Type registrations are assumed to be general; meaning that registration of serializer * for a super type will also be used for handling subtypes, unless an exact match * is found first. As an example, handler for {@link CharSequence} would also be used * serializing {@link StringBuilder} instances, unless a direct mapping was found. */
public class SimpleSerializers extends Serializers.Base implements java.io.Serializable { private static final long serialVersionUID = 8531646511998456779L;
Class-based mappings that are used both for exact and sub-class matches.
/** * Class-based mappings that are used both for exact and * sub-class matches. */
protected HashMap<ClassKey,JsonSerializer<?>> _classMappings = null;
Interface-based matches.
/** * Interface-based matches. */
protected HashMap<ClassKey,JsonSerializer<?>> _interfaceMappings = null;
Flag to help find "generic" enum serializer, if one has been registered.
Since:2.3
/** * Flag to help find "generic" enum serializer, if one has been registered. * * @since 2.3 */
protected boolean _hasEnumSerializer = false; /* /********************************************************** /* Life-cycle, construction and configuring /********************************************************** */ public SimpleSerializers() { }
Since:2.1
/** * @since 2.1 */
public SimpleSerializers(List<JsonSerializer<?>> sers) { addSerializers(sers); }
Method for adding given serializer for type that JsonSerializer.handledType specifies (which MUST return a non-null class; and can NOT be Object, as a sanity check). For serializers that do not declare handled type, use the variant that takes two arguments.
Params:
  • ser –
/** * Method for adding given serializer for type that {@link JsonSerializer#handledType} * specifies (which MUST return a non-null class; and can NOT be {@link Object}, as a * sanity check). * For serializers that do not declare handled type, use the variant that takes * two arguments. * * @param ser */
public void addSerializer(JsonSerializer<?> ser) { // Interface to match? Class<?> cls = ser.handledType(); if (cls == null || cls == Object.class) { throw new IllegalArgumentException("JsonSerializer of type "+ser.getClass().getName() +" does not define valid handledType() -- must either register with method that takes type argument " +" or make serializer extend 'com.fasterxml.jackson.databind.ser.std.StdSerializer'"); } _addSerializer(cls, ser); } public <T> void addSerializer(Class<? extends T> type, JsonSerializer<T> ser) { _addSerializer(type, ser); }
Since:2.1
/** * @since 2.1 */
public void addSerializers(List<JsonSerializer<?>> sers) { for (JsonSerializer<?> ser : sers) { addSerializer(ser); } } /* /********************************************************** /* Serializers implementation /********************************************************** */ @Override public JsonSerializer<?> findSerializer(SerializationConfig config, JavaType type, BeanDescription beanDesc) { Class<?> cls = type.getRawClass(); ClassKey key = new ClassKey(cls); JsonSerializer<?> ser = null; // First: direct match? if (cls.isInterface()) { if (_interfaceMappings != null) { ser = _interfaceMappings.get(key); if (ser != null) { return ser; } } } else { if (_classMappings != null) { ser = _classMappings.get(key); if (ser != null) { return ser; } // [Issue#227]: Handle registration of plain `Enum` serializer if (_hasEnumSerializer && type.isEnumType()) { key.reset(Enum.class); ser = _classMappings.get(key); if (ser != null) { return ser; } } // If not direct match, maybe super-class match? for (Class<?> curr = cls; (curr != null); curr = curr.getSuperclass()) { key.reset(curr); ser = _classMappings.get(key); if (ser != null) { return ser; } } } } // No direct match? How about super-interfaces? if (_interfaceMappings != null) { ser = _findInterfaceMapping(cls, key); if (ser != null) { return ser; } // still no matches? Maybe interfaces of super classes if (!cls.isInterface()) { while ((cls = cls.getSuperclass()) != null) { ser = _findInterfaceMapping(cls, key); if (ser != null) { return ser; } } } } return null; } @Override public JsonSerializer<?> findArraySerializer(SerializationConfig config, ArrayType type, BeanDescription beanDesc, TypeSerializer elementTypeSerializer, JsonSerializer<Object> elementValueSerializer) { return findSerializer(config, type, beanDesc); } @Override public JsonSerializer<?> findCollectionSerializer(SerializationConfig config, CollectionType type, BeanDescription beanDesc, TypeSerializer elementTypeSerializer, JsonSerializer<Object> elementValueSerializer) { return findSerializer(config, type, beanDesc); } @Override public JsonSerializer<?> findCollectionLikeSerializer(SerializationConfig config, CollectionLikeType type, BeanDescription beanDesc, TypeSerializer elementTypeSerializer, JsonSerializer<Object> elementValueSerializer) { return findSerializer(config, type, beanDesc); } @Override public JsonSerializer<?> findMapSerializer(SerializationConfig config, MapType type, BeanDescription beanDesc, JsonSerializer<Object> keySerializer, TypeSerializer elementTypeSerializer, JsonSerializer<Object> elementValueSerializer) { return findSerializer(config, type, beanDesc); } @Override public JsonSerializer<?> findMapLikeSerializer(SerializationConfig config, MapLikeType type, BeanDescription beanDesc, JsonSerializer<Object> keySerializer, TypeSerializer elementTypeSerializer, JsonSerializer<Object> elementValueSerializer) { return findSerializer(config, type, beanDesc); } /* /********************************************************** /* Internal methods /********************************************************** */ protected JsonSerializer<?> _findInterfaceMapping(Class<?> cls, ClassKey key) { for (Class<?> iface : cls.getInterfaces()) { key.reset(iface); JsonSerializer<?> ser = _interfaceMappings.get(key); if (ser != null) { return ser; } ser = _findInterfaceMapping(iface, key); if (ser != null) { return ser; } } return null; } protected void _addSerializer(Class<?> cls, JsonSerializer<?> ser) { ClassKey key = new ClassKey(cls); // Interface or class type? if (cls.isInterface()) { if (_interfaceMappings == null) { _interfaceMappings = new HashMap<ClassKey,JsonSerializer<?>>(); } _interfaceMappings.put(key, ser); } else { // nope, class: if (_classMappings == null) { _classMappings = new HashMap<ClassKey,JsonSerializer<?>>(); } _classMappings.put(key, ser); if (cls == Enum.class) { _hasEnumSerializer = true; } } } }