Create the MappingPdxSerializerIncludedTypesRegistrar utility class and Spring BeanPostProcessor used to register additional class types to be 'included' in the accepted types de/serialized as PDX with the SDG MappingPdxSerializer.

spring-geode/src/main/java/org/springframework/geode/pdx/MappingPdxSerializerIncludedTypesRegistrar.java

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+/*
+ * Copyright 2020 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+package org.springframework.geode.pdx;
+
+import java.util.Arrays;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.function.Predicate;
+
+import org.apache.geode.cache.GemFireCache;
+import org.apache.geode.pdx.PdxSerializer;
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.config.BeanPostProcessor;
+import org.springframework.data.gemfire.mapping.MappingPdxSerializer;
+import org.springframework.data.gemfire.util.ArrayUtils;
+import org.springframework.lang.NonNull;
+import org.springframework.lang.Nullable;
+
+/**
+ * Spring {@link BeanPostProcessor} used to register additional {@link Class types} handled by
+ * the SDG {@link MappingPdxSerializer}.
+ *
+ * @author John Blum
+ * @see java.lang.Class
+ * @see java.util.function.Predicate
+ * @see org.apache.geode.cache.GemFireCache
+ * @see org.apache.geode.pdx.PdxSerializer
+ * @see org.springframework.beans.factory.config.BeanPostProcessor
+ * @see org.springframework.data.gemfire.mapping.MappingPdxSerializer
+ * @since 1.5.0
+ */
+@SuppressWarnings("unused")
+public class MappingPdxSerializerIncludedTypesRegistrar implements BeanPostProcessor {
+
+	/**
+	 * Factory methods used to construct a new instance of {@link MappingPdxSerializerIncludedTypesRegistrar}
+	 * initialized with given, required array of {@link Class} types that will be registered with
+	 * SDG's {@link MappingPdxSerializer} in order to de/serialize the specified {@link Class} types as PDX.
+	 *
+	 * @param types array of {@link Class} types to be de/serialized as PDX using SDG's {@link MappingPdxSerializer};
+	 * must not be {@literal null}.
+	 * @return a new instance of {@link MappingPdxSerializerIncludedTypesRegistrar}
+	 * @see #MappingPdxSerializerIncludedTypesRegistrar(Class[])
+	 */
+	public static @NonNull MappingPdxSerializerIncludedTypesRegistrar with(Class<?>... types) {
+		return new MappingPdxSerializerIncludedTypesRegistrar(types);
+	}
+
+	private final Class<?>[] types;
+
+	/**
+	 * Constructs a new instance of {@link MappingPdxSerializerIncludedTypesRegistrar} initialized with given,
+	 * required array of {@link Class} types that will be registered with SDG's {@link MappingPdxSerializer}
+	 * in order to de/serialize the specified {@link Class} types as PDX.
+	 *
+	 * @param types array of {@link Class} types to be de/serialized as PDX using SDG's {@link MappingPdxSerializer};
+	 * must not be {@literal null}.
+	 * @see java.lang.Class
+	 */
+	public MappingPdxSerializerIncludedTypesRegistrar(@NonNull Class<?>[] types) {
+
+		this.types = Arrays.stream(ArrayUtils.nullSafeArray(types, Class.class))
+			.filter(Objects::nonNull)
+			.toArray(Class[]::new);
+	}
+
+	/**
+	 * Gets the array of {@link Class} types to register with SDG's {@link MappingPdxSerializer} in order to
+	 * de/serialize the {@link Class} types as PDX.
+	 *
+	 * @return the configured array of {@link Class} types to be registered with SDG's {@link MappingPdxSerializer}
+	 * in order to de/serialize the {@link Class} types as PDX; never {@literal null}.
+	 * @see java.lang.Class
+	 */
+	protected @NonNull Class<?>[] getTypes() {
+		return this.types;
+	}
+
+	/**
+	 * Composes an {@link Optional} {@link Predicate} consisting of the configured array {@link Class} types
+	 * used to match possible types de/serialized as PDX using SDG's {@link MappingPdxSerializer}.
+	 *
+	 * @return an {@link Optional} composite {@link Predicate} consisting of the configured
+	 * array of {@link Class} types.
+	 * @see java.util.function.Predicate
+	 * @see java.util.Optional
+	 * @see #getTypes()
+	 */
+	protected Optional<Predicate<Class<?>>> getCompositeIncludeTypeFilter() {
+
+		Predicate<Class<?>> compositeIncludeTypeFilter = null;
+
+		for (Class<?> type : getTypes()) {
+			if (type != null) {
+				compositeIncludeTypeFilter = compositeIncludeTypeFilter != null
+					? compositeIncludeTypeFilter.or(newIncludeTypeFilter(type))
+					: newIncludeTypeFilter(type);
+			}
+		}
+
+		return Optional.ofNullable(compositeIncludeTypeFilter);
+	}
+
+	/**
+	 * Null-safe method used to construct a new {@link Class type} include {@link Predicate filter}
+	 * that can be registered with SDG's {@link MappingPdxSerializer}.
+	 *
+	 * The {@link Predicate} matches tested {@link Class types} that are
+	 * {@link Class#isAssignableFrom(Class) assignable from} the given {@link Class type}.
+	 *
+	 * @param type {@link Class} used as the basis for matching in the {@link Predicate}.
+	 * @return an (optional} {@link Predicate} from the given {@link Class type};
+	 * returns {@literal null} if the given {@link Class type} is {@literal null}.
+	 * @see java.util.function.Predicate
+	 * @see java.lang.Class
+	 */
+	protected @Nullable Predicate<Class<?>> newIncludeTypeFilter(@Nullable Class<?> type) {
+
+		return type != null
+			? testType -> Objects.nonNull(testType) && type.isAssignableFrom(testType)
+			: null;
+	}
+
+	/**
+	 * Registers the configured {@link Class} types with SDG's {@link MappingPdxSerializer} providing the bean
+	 * to post process after initialization is a {@link GemFireCache} instance and SDG's {@link MappingPdxSerializer}
+	 * was configured as the cache's {@link PdxSerializer} used to de/serialize objects of the specified {@link Class}
+	 * types.
+	 *
+	 * @param bean {@link Object bean} to evaluate.
+	 * @param beanName {@link String} specifying the {@literal name} of the bean in the Spring container.
+	 * @return the given {@link Object} bean.
+	 * @throws BeansException if post processing of the bean fails.
+	 */
+	@Override
+	public @Nullable Object postProcessAfterInitialization(@Nullable Object bean, @Nullable String beanName)
+			throws BeansException {
+
+		if (bean instanceof GemFireCache) {
+
+			GemFireCache cache = (GemFireCache) bean;
+
+			PdxSerializer pdxSerializer = cache.getPdxSerializer();
+
+			if (pdxSerializer instanceof MappingPdxSerializer) {
+
+				MappingPdxSerializer mappingPdxSerializer = (MappingPdxSerializer) pdxSerializer;
+
+				getCompositeIncludeTypeFilter().ifPresent(mappingPdxSerializer::setIncludeTypeFilters);
+			}
+		}
+
+		return bean;
+	}
+}