Support for Jackson's default typing via TypeResolverBuilder

Issue: SPR-13569

Author: jhoeller

spring-web/src/main/java/org/springframework/http/converter/json/Jackson2ObjectMapperBuilder.java

@@ -44,6 +44,7 @@
 import com.fasterxml.jackson.databind.PropertyNamingStrategy;
 import com.fasterxml.jackson.databind.SerializationFeature;
 import com.fasterxml.jackson.databind.cfg.HandlerInstantiator;
+import com.fasterxml.jackson.databind.jsontype.TypeResolverBuilder;
 import com.fasterxml.jackson.databind.module.SimpleModule;
 import com.fasterxml.jackson.databind.ser.FilterProvider;
 import com.fasterxml.jackson.dataformat.xml.XmlMapper;
@@ -98,6 +99,8 @@ public class Jackson2ObjectMapperBuilder {
 
 	private PropertyNamingStrategy propertyNamingStrategy;
 
+	private TypeResolverBuilder<?> defaultTyping;
+
 	private JsonInclude.Include serializationInclusion;
 
 	private FilterProvider filters;
@@ -216,6 +219,15 @@ public Jackson2ObjectMapperBuilder propertyNamingStrategy(PropertyNamingStrategy
 		return this;
 	}
 
+	/**
+	 * Specify a {@link TypeResolverBuilder} to use for Jackson's default typing.
+	 * @since 4.2.2
+	 */
+	public Jackson2ObjectMapperBuilder defaultTyping(TypeResolverBuilder<?> typeResolverBuilder) {
+		this.defaultTyping = typeResolverBuilder;
+		return this;
+	}
+
 	/**
 	 * Set a custom inclusion strategy for serialization.
 	 * @see com.fasterxml.jackson.annotation.JsonInclude.Include
@@ -523,6 +535,7 @@ public Jackson2ObjectMapperBuilder applicationContext(ApplicationContext applica
 		return this;
 	}
 
+
 	/**
 	 * Build a new {@link ObjectMapper} instance.
 	 * <p>Each build operation produces an independent {@link ObjectMapper} instance.
@@ -588,6 +601,9 @@ else if (this.findWellKnownModules) {
 		if (this.propertyNamingStrategy != null) {
 			objectMapper.setPropertyNamingStrategy(this.propertyNamingStrategy);
 		}
+		if (this.defaultTyping != null) {
+			objectMapper.setDefaultTyping(this.defaultTyping);
+		}
 		if (this.serializationInclusion != null) {
 			objectMapper.setSerializationInclusion(this.serializationInclusion);
 		}
@@ -623,6 +639,7 @@ else if (this.applicationContext != null) {
 		}
 	}
 
+
 	// Any change to this method should be also applied to spring-jms and spring-messaging
 	// MappingJackson2MessageConverter default constructors
 	private void customizeDefaultFeatures(ObjectMapper objectMapper) {

spring-web/src/main/java/org/springframework/http/converter/json/Jackson2ObjectMapperFactoryBean.java

@@ -36,6 +36,7 @@
 import com.fasterxml.jackson.databind.PropertyNamingStrategy;
 import com.fasterxml.jackson.databind.SerializationFeature;
 import com.fasterxml.jackson.databind.cfg.HandlerInstantiator;
+import com.fasterxml.jackson.databind.jsontype.TypeResolverBuilder;
 import com.fasterxml.jackson.databind.ser.FilterProvider;
 import com.fasterxml.jackson.dataformat.xml.XmlMapper;
 
@@ -215,6 +216,14 @@ public void setPropertyNamingStrategy(PropertyNamingStrategy propertyNamingStrat
 		this.builder.propertyNamingStrategy(propertyNamingStrategy);
 	}
 
+	/**
+	 * Specify a {@link TypeResolverBuilder} to use for Jackson's default typing.
+	 * @since 4.2.2
+	 */
+	public void setDefaultTyping(TypeResolverBuilder<?> typeResolverBuilder) {
+		this.builder.defaultTyping(typeResolverBuilder);
+	}
+
 	/**
 	 * Set a custom inclusion strategy for serialization.
 	 * @see com.fasterxml.jackson.annotation.JsonInclude.Include
@@ -223,6 +232,27 @@ public void setSerializationInclusion(JsonInclude.Include serializationInclusion
 		this.builder.serializationInclusion(serializationInclusion);
 	}
 
+	/**
+	 * Set the global filters to use in order to support {@link JsonFilter @JsonFilter} annotated POJO.
+	 * @since 4.2
+	 * @see Jackson2ObjectMapperBuilder#filters(FilterProvider)
+	 */
+	public void setFilters(FilterProvider filters) {
+		this.builder.filters(filters);
+	}
+
+	/**
+	 * Add mix-in annotations to use for augmenting specified class or interface.
+	 * @param mixIns Map of entries with target classes (or interface) whose annotations
+	 * to effectively override as key and mix-in classes (or interface) whose
+	 * annotations are to be "added" to target's annotations as value.
+	 * @since 4.1.2
+	 * @see com.fasterxml.jackson.databind.ObjectMapper#addMixInAnnotations(Class, Class)
+	 */
+	public void setMixIns(Map<Class<?>, Class<?>> mixIns) {
+		this.builder.mixIns(mixIns);
+	}
+
 	/**
 	 * Configure custom serializers. Each serializer is registered for the type
 	 * returned by {@link JsonSerializer#handledType()}, which must not be
@@ -248,18 +278,6 @@ public void setDeserializersByType(Map<Class<?>, JsonDeserializer<?>> deserializ
 		this.builder.deserializersByType(deserializers);
 	}
 
-	/**
-	 * Add mix-in annotations to use for augmenting specified class or interface.
-	 * @param mixIns Map of entries with target classes (or interface) whose annotations
-	 * to effectively override as key and mix-in classes (or interface) whose
-	 * annotations are to be "added" to target's annotations as value.
-	 * @since 4.1.2
-	 * @see com.fasterxml.jackson.databind.ObjectMapper#addMixInAnnotations(Class, Class)
-	 */
-	public void setMixIns(Map<Class<?>, Class<?>> mixIns) {
-		this.builder.mixIns(mixIns);
-	}
-
 	/**
 	 * Shortcut for {@link MapperFeature#AUTO_DETECT_FIELDS} option.
 	 */
@@ -373,6 +391,11 @@ public void setFindModulesViaServiceLoader(boolean findModules) {
 		this.builder.findModulesViaServiceLoader(findModules);
 	}
 
+	@Override
+	public void setBeanClassLoader(ClassLoader beanClassLoader) {
+		this.builder.moduleClassLoader(beanClassLoader);
+	}
+
 	/**
 	 * Customize the construction of Jackson handlers ({@link JsonSerializer}, {@link JsonDeserializer},
 	 * {@link KeyDeserializer}, {@code TypeResolverBuilder} and {@code TypeIdResolver}).
@@ -384,17 +407,15 @@ public void setHandlerInstantiator(HandlerInstantiator handlerInstantiator) {
 	}
 
 	/**
-	 * Set the global filters to use in order to support {@link JsonFilter @JsonFilter} annotated POJO.
-	 * @since 4.2
-	 * @see Jackson2ObjectMapperBuilder#filters(FilterProvider)
+	 * Set the builder {@link ApplicationContext} in order to autowire Jackson handlers ({@link JsonSerializer},
+	 * {@link JsonDeserializer}, {@link KeyDeserializer}, {@code TypeResolverBuilder} and {@code TypeIdResolver}).
+	 * @since 4.1.3
+	 * @see Jackson2ObjectMapperBuilder#applicationContext(ApplicationContext)
+	 * @see SpringHandlerInstantiator
 	 */
-	public void setFilters(FilterProvider filters) {
-		this.builder.filters(filters);
-	}
-
 	@Override
-	public void setBeanClassLoader(ClassLoader beanClassLoader) {
-		this.builder.moduleClassLoader(beanClassLoader);
+	public void setApplicationContext(ApplicationContext applicationContext) {
+		this.builder.applicationContext(applicationContext);
 	}
 
 
@@ -408,18 +429,6 @@ public void afterPropertiesSet() {
 		}
 	}
 
-	/**
-	 * Set the builder {@link ApplicationContext} in order to autowire Jackson handlers ({@link JsonSerializer},
-	 * {@link JsonDeserializer}, {@link KeyDeserializer}, {@code TypeResolverBuilder} and {@code TypeIdResolver}).
-	 * @since 4.1.3
-	 * @see Jackson2ObjectMapperBuilder#applicationContext(ApplicationContext)
-	 * @see SpringHandlerInstantiator
-	 */
-	@Override
-	public void setApplicationContext(ApplicationContext applicationContext) {
-		this.builder.applicationContext(applicationContext);
-	}
-
 	/**
 	 * Return the singleton ObjectMapper.
 	 */