Switch Jackson default mapping default from NON_FINAL to EVERYTHING.

Closes #1566
Original pull request: #2237.

Author: christophstrobl

src/main/java/org/springframework/data/redis/hash/Jackson2HashMapper.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.data.redis.hash;
 
+import static com.fasterxml.jackson.databind.ObjectMapper.DefaultTyping.*;
+
 import java.io.IOException;
 import java.text.ParseException;
 import java.util.ArrayList;
@@ -39,8 +41,10 @@
 import com.fasterxml.jackson.annotation.JsonTypeInfo.As;
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.TreeNode;
 import com.fasterxml.jackson.databind.DeserializationContext;
 import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.JsonDeserializer;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.JsonSerializer;
@@ -49,7 +53,9 @@
 import com.fasterxml.jackson.databind.SerializationFeature;
 import com.fasterxml.jackson.databind.SerializerProvider;
 import com.fasterxml.jackson.databind.deser.std.UntypedObjectDeserializer;
+import com.fasterxml.jackson.databind.jsontype.PolymorphicTypeValidator;
 import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
+import com.fasterxml.jackson.databind.jsontype.TypeResolverBuilder;
 import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
 import com.fasterxml.jackson.databind.module.SimpleModule;
 import com.fasterxml.jackson.databind.ser.std.CalendarSerializer;
@@ -157,9 +163,30 @@ public class Jackson2HashMapper implements HashMapper<Object, String, Object> {
 	 */
 	public Jackson2HashMapper(boolean flatten) {
 
-		this(new ObjectMapper().findAndRegisterModules(), flatten);
+		this(new ObjectMapper() {
+
+			@Override
+			protected TypeResolverBuilder<?> _constructDefaultTypeResolverBuilder(DefaultTyping applicability,
+					PolymorphicTypeValidator ptv) {
+				return new DefaultTypeResolverBuilder(applicability, ptv) {
+					public boolean useForType(JavaType t) {
+
+						if (t.isPrimitive()) {
+							return false;
+						}
+
+						if (EVERYTHING.equals(_appliesFor)) {
+							return !TreeNode.class.isAssignableFrom(t.getRawClass());
+						}
+
+						return super.useForType(t);
+					}
+				};
+			}
+		}.findAndRegisterModules(), flatten);
 
-		typingMapper.enableDefaultTyping(DefaultTyping.NON_FINAL, As.PROPERTY);
+		typingMapper.activateDefaultTyping(typingMapper.getPolymorphicTypeValidator(), DefaultTyping.EVERYTHING,
+				As.PROPERTY);
 		typingMapper.configure(SerializationFeature.WRITE_NULL_MAP_VALUES, false);
 
 		// Prevent splitting time types into arrays. E

src/main/java/org/springframework/data/redis/serializer/GenericJackson2JsonRedisSerializer.java

@@ -30,6 +30,7 @@
 import com.fasterxml.jackson.databind.ObjectMapper.DefaultTyping;
 import com.fasterxml.jackson.databind.SerializerProvider;
 import com.fasterxml.jackson.databind.jsontype.PolymorphicTypeValidator;
+import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
 import com.fasterxml.jackson.databind.module.SimpleModule;
 import com.fasterxml.jackson.databind.ser.SerializerFactory;
 import com.fasterxml.jackson.databind.ser.std.StdSerializer;
@@ -71,10 +72,10 @@ public GenericJackson2JsonRedisSerializer(@Nullable String classPropertyTypeName
 		registerNullValueSerializer(mapper, classPropertyTypeName);
 
 		if (StringUtils.hasText(classPropertyTypeName)) {
-			mapper.activateDefaultTypingAsProperty(mapper.getPolymorphicTypeValidator(), DefaultTyping.NON_FINAL,
+			mapper.activateDefaultTypingAsProperty(mapper.getPolymorphicTypeValidator(), DefaultTyping.EVERYTHING,
 					classPropertyTypeName);
 		} else {
-			mapper.activateDefaultTyping(mapper.getPolymorphicTypeValidator(), DefaultTyping.NON_FINAL, As.PROPERTY);
+			mapper.activateDefaultTyping(mapper.getPolymorphicTypeValidator(), DefaultTyping.EVERYTHING, As.PROPERTY);
 		}
 	}
 
@@ -190,5 +191,11 @@ public void serialize(NullValue value, JsonGenerator jgen, SerializerProvider pr
 			jgen.writeStringField(classIdentifier, NullValue.class.getName());
 			jgen.writeEndObject();
 		}
+
+		@Override
+		public void serializeWithType(NullValue value, JsonGenerator gen, SerializerProvider serializers,
+				TypeSerializer typeSer) throws IOException {
+			serialize(value, gen, serializers);
+		}
 	}
 }

src/test/java/org/springframework/data/redis/mapping/Jackson2HashMapperUnitTests.java

@@ -183,6 +183,15 @@ void dateValueShouldBeTreatedCorrectly() {
 		assertBackAndForwardMapping(source);
 	}
 
+	@Test // GH-1566
+	void mapFinalClass() {
+
+		MeFinal source = new MeFinal();
+		source.value = "id-1";
+
+		assertBackAndForwardMapping(source);
+	}
+
 	@Data
 	public static class WithList {
 		List<String> strings;
@@ -206,4 +215,9 @@ private static class WithDates {
 		private LocalDate localDate;
 		private LocalDateTime localDateTime;
 	}
+
+	@Data
+	public static final class MeFinal {
+		private String value;
+	}
 }

src/test/java/org/springframework/data/redis/serializer/GenericJackson2JsonRedisSerializerUnitTests.java

@@ -20,11 +20,12 @@
 import static org.springframework.test.util.ReflectionTestUtils.*;
 import static org.springframework.util.ObjectUtils.*;
 
+import lombok.Data;
+
 import java.io.IOException;
 
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
-
 import org.springframework.beans.BeanUtils;
 import org.springframework.cache.support.NullValue;
 
@@ -141,14 +142,26 @@ void shouldSerializeNullValueSoThatItCanBeDeserializedWithDefaultTypingEnabled()
 	void shouldSerializeNullValueWithCustomObjectMapper() {
 
 		ObjectMapper mapper = new ObjectMapper();
-		mapper.enableDefaultTyping(DefaultTyping.NON_FINAL, As.PROPERTY);
+		mapper.enableDefaultTyping(DefaultTyping.EVERYTHING, As.PROPERTY);
 
 		GenericJackson2JsonRedisSerializer.registerNullValueSerializer(mapper, null);
 		GenericJackson2JsonRedisSerializer serializer = new GenericJackson2JsonRedisSerializer(mapper);
 
 		serializeAndDeserializeNullValue(serializer);
 	}
 
+	@Test // GH-1566
+	void deserializeShouldBeAbleToRestoreFinalObjectAfterSerialization() {
+
+		GenericJackson2JsonRedisSerializer serializer = new GenericJackson2JsonRedisSerializer();
+
+		FinalObject source = new FinalObject();
+		source.longValue = 1L;
+		source.simpleObject = new SimpleObject(2L);
+
+		assertThat(serializer.deserialize(serializer.serialize(source))).isEqualTo(source);
+	}
+
 	private static void serializeAndDeserializeNullValue(GenericJackson2JsonRedisSerializer serializer) {
 
 		NullValue nv = BeanUtils.instantiateClass(NullValue.class);
@@ -201,6 +214,12 @@ public boolean equals(Object obj) {
 
 	}
 
+	@Data
+	static final class FinalObject {
+		public Long longValue;
+		SimpleObject simpleObject;
+	}
+
 	static class SimpleObject {
 
 		public Long longValue;