feat: create builder class

Author: AnneMayor

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

@@ -18,6 +18,7 @@
 import java.io.IOException;
 import java.io.Serial;
 import java.util.Collections;
+import java.util.Objects;
 import java.util.function.Consumer;
 import java.util.function.Supplier;
 
@@ -120,39 +121,9 @@ public GenericJackson2JsonRedisSerializer(@Nullable String classPropertyTypeName
 	public GenericJackson2JsonRedisSerializer(@Nullable String classPropertyTypeName, JacksonObjectReader reader,
 			JacksonObjectWriter writer) {
 
-		this(classPropertyTypeName, reader, writer, null);
-	}
-
-	/**
-	 * Creates {@link GenericJackson2JsonRedisSerializer} initialized with an {@link ObjectMapper} configured for default
-	 * typing using the given {@link String name} along with the given, required {@link JacksonObjectReader} and
-	 * {@link JacksonObjectWriter} used to read/write {@link Object Objects} de/serialized as JSON,
-	 * optionally customized {@link NullValueSerializer}.
-	 * <p>
-	 * In case {@link String name} is {@literal empty} or {@literal null}, then {@link JsonTypeInfo.Id#CLASS} will be
-	 * used.
-	 * <p>
-	 * In case {@link StdSerializer} is {@literal null}, then a default {@link NullValueSerializer} will be registered.
-	 *
-	 * @param classPropertyTypeName {@link String name} of the JSON property holding type information; can be
-	 *          {@literal null}.
-	 * @param reader {@link JacksonObjectReader} function to read objects using {@link ObjectMapper}.
-	 * @param writer {@link JacksonObjectWriter} function to write objects using {@link ObjectMapper}.
-	 * @param nullValueSerializer {@link StdSerializer} to serialize {@link NullValue} instances.
-	 * @see ObjectMapper#activateDefaultTypingAsProperty(PolymorphicTypeValidator, DefaultTyping, String)
-	 * @see ObjectMapper#activateDefaultTyping(PolymorphicTypeValidator, DefaultTyping, As)
-	 * @since 3.3
-	 */
-	public GenericJackson2JsonRedisSerializer(@Nullable String classPropertyTypeName, JacksonObjectReader reader,
-			JacksonObjectWriter writer, @Nullable StdSerializer<NullValue> nullValueSerializer) {
-
 		this(new ObjectMapper(), reader, writer, classPropertyTypeName);
 
-		if (nullValueSerializer == null) {
-			registerNullValueSerializer(this.mapper, classPropertyTypeName);
-		} else {
-			registerCustomNullValueSerializer(nullValueSerializer);
-		}
+		registerNullValueSerializer(this.mapper, classPropertyTypeName);
 
 		StdTypeResolverBuilder typer = TypeResolverBuilder.forEverything(this.mapper).init(JsonTypeInfo.Id.CLASS, null)
 				.inclusion(JsonTypeInfo.As.PROPERTY);
@@ -164,6 +135,10 @@ public GenericJackson2JsonRedisSerializer(@Nullable String classPropertyTypeName
 		this.mapper.setDefaultTyping(typer);
 	}
 
+	public static GenericJackson2JsonRedisSerializerBuilder builder() {
+		return new GenericJackson2JsonRedisSerializerBuilder();
+	}
+
 	/**
 	 * Setting a custom-configured {@link ObjectMapper} is one way to take further control of the JSON serialization
 	 * process. For example, an extended {@link SerializerFactory} can be configured that provides custom serializers for
@@ -261,10 +236,6 @@ public static void registerNullValueSerializer(ObjectMapper objectMapper, @Nulla
 		objectMapper.registerModule(new SimpleModule().addSerializer(new NullValueSerializer(classPropertyTypeName)));
 	}
 
-	private void registerCustomNullValueSerializer(StdSerializer<NullValue> nullValueSerializer) {
-		this.mapper.registerModule(new SimpleModule().addSerializer(nullValueSerializer));
-	}
-
 	/**
 	 * Gets the configured {@link ObjectMapper} used internally by this {@link GenericJackson2JsonRedisSerializer} to
 	 * de/serialize {@link Object objects} as {@literal JSON}.
@@ -430,6 +401,46 @@ public void serializeWithType(NullValue value, JsonGenerator jsonGenerator, Seri
 		}
 	}
 
+	public static class GenericJackson2JsonRedisSerializerBuilder {
+		private GenericJackson2JsonRedisSerializerBuilder() {}
+
+		@Nullable
+		private String classPropertyTypeName;
+		private JacksonObjectReader reader;
+		private JacksonObjectWriter writer;
+		private ObjectMapper mapper;
+
+		public GenericJackson2JsonRedisSerializerBuilder classPropertyTypeName(@Nullable String classPropertyTypeName) {
+			this.classPropertyTypeName = classPropertyTypeName;
+			return this;
+		}
+
+		public GenericJackson2JsonRedisSerializerBuilder objectReader(JacksonObjectReader reader) {
+			this.reader = reader;
+			return this;
+		}
+
+		public GenericJackson2JsonRedisSerializerBuilder objectWriter(JacksonObjectWriter writer) {
+			this.writer = writer;
+			return this;
+		}
+
+		public GenericJackson2JsonRedisSerializerBuilder objectMapper(ObjectMapper mapper) {
+			this.mapper = mapper;
+			return this;
+		}
+
+		public GenericJackson2JsonRedisSerializerBuilder registerNullValueSerializer(@Nullable StdSerializer<NullValue> nullValueSerializer) {
+			this.mapper.registerModule(new SimpleModule().addSerializer(Objects.requireNonNullElseGet(nullValueSerializer, () -> new NullValueSerializer(this.classPropertyTypeName))));
+
+			return this;
+		}
+
+		public GenericJackson2JsonRedisSerializer build() {
+			return new GenericJackson2JsonRedisSerializer(this.mapper, this.reader, this.writer, this.classPropertyTypeName);
+		}
+	}
+
 	/**
 	 * Custom {@link StdTypeResolverBuilder} that considers typing for non-primitive types. Primitives, their wrappers and
 	 * primitive arrays do not require type hints. The default {@code DefaultTyping#EVERYTHING} typing does not satisfy

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

@@ -451,30 +451,42 @@ void configureWithNullConsumerThrowsIllegalArgumentException() {
 	}
 
 	@Test
-	void customSerializeAndDeserializeNullValue() {
+	void defaultSerializeAndDeserializeNullValueWithBuilderClass() {
+		GenericJackson2JsonRedisSerializer serializer = GenericJackson2JsonRedisSerializer.builder()
+				.objectMapper(new ObjectMapper().enableDefaultTyping(DefaultTyping.EVERYTHING, As.PROPERTY))
+				.objectReader(JacksonObjectReader.create())
+				.objectWriter(JacksonObjectWriter.create())
+				.classPropertyTypeName(null)
+				.registerNullValueSerializer(null)
+				.build();
 
-		GenericJackson2JsonRedisSerializer serializer = new GenericJackson2JsonRedisSerializer(
-				null,
-				(mapper, source, type) -> {
-					if (type.getRawClass() == User.class) {
-						return mapper.readerWithView(Views.Basic.class).forType(type).readValue(source);
+		serializeAndDeserializeNullValue(serializer);
+	}
+
+	@Test
+	void customSerializeAndDeserializeNullValueWithBuilderClass() {
+		GenericJackson2JsonRedisSerializer serializer = GenericJackson2JsonRedisSerializer.builder()
+				.objectMapper(new ObjectMapper())
+				.objectReader(JacksonObjectReader.create())
+				.objectWriter(JacksonObjectWriter.create())
+				.classPropertyTypeName(null)
+				.registerNullValueSerializer(new StdSerializer<>(NullValue.class) {
+					@Override
+					public void serialize(NullValue nullValue,
+					                      JsonGenerator jsonGenerator,
+					                      SerializerProvider serializerProvider) throws IOException {
+						jsonGenerator.writeNull();
 					}
-					return mapper.readValue(source, type);
-				}, JacksonObjectWriter.create(), new StdSerializer<>(NullValue.class) {
-			@Override
-			public void serialize(NullValue nullValue,
-								  JsonGenerator jsonGenerator,
-								  SerializerProvider serializerProvider) throws IOException {
-				jsonGenerator.writeNull();
-			}
 
-			@Override
-			public void serializeWithType(NullValue value, JsonGenerator jsonGenerator, SerializerProvider serializers,
-			                              TypeSerializer typeSerializer) throws IOException {
+					@Override
+					public void serializeWithType(NullValue value, JsonGenerator jsonGenerator, SerializerProvider serializers,
+					                              TypeSerializer typeSerializer) throws IOException {
+
+						serialize(value, jsonGenerator, serializers);
+					}
+				})
+				.build();
 
-				serialize(value, jsonGenerator, serializers);
-			}
-		});
 
 		NullValue nv = BeanUtils.instantiateClass(NullValue.class);