Apply converters on simple value reads.

We now apply converters for simple value reads ensuring that e.g. Enum converters are applied.

Closes #1689

Author: mp911de

spring-data-relational/src/main/java/org/springframework/data/relational/core/conversion/MappingRelationalConverter.java

@@ -307,7 +307,7 @@ protected <S> S read(TypeInformation<S> type, RowDocument source) {
 	 * @return the converted object, will never be {@literal null}.
 	 */
 	protected <S> S readAggregate(ConversionContext context, RowDocument document,
-								  TypeInformation<? extends S> typeHint) {
+			TypeInformation<? extends S> typeHint) {
 		return readAggregate(context, new RowDocumentAccessor(document), typeHint);
 	}
 
@@ -321,7 +321,7 @@ protected <S> S readAggregate(ConversionContext context, RowDocument document,
 	 */
 	@SuppressWarnings("unchecked")
 	protected <S> S readAggregate(ConversionContext context, RowDocumentAccessor documentAccessor,
-								  TypeInformation<? extends S> typeHint) {
+			TypeInformation<? extends S> typeHint) {
 
 		Class<? extends S> rawType = typeHint.getType();
 
@@ -430,8 +430,7 @@ private <T> T doConvert(Object value, Class<? extends T> target) {
 	}
 
 	@SuppressWarnings("ConstantConditions")
-	private <T> T doConvert(Object value, Class<? extends T> target,
-							@Nullable Class<? extends T> fallback) {
+	private <T> T doConvert(Object value, Class<? extends T> target, @Nullable Class<? extends T> fallback) {
 
 		if (getConversionService().canConvert(value.getClass(), target) || fallback == null) {
 			return getConversionService().convert(value, target);
@@ -504,7 +503,7 @@ public RelationalPropertyValueProvider withContext(ConversionContext context) {
 				entity, contextualizing, context.getPath().getCurrentObject());
 
 		return new ConverterAwareSpELExpressionParameterValueProvider(context, evaluator, getConversionService(),
-				new ConvertingParameterValueProvider<>( parameterProvider::getParameterValue));
+				new ConvertingParameterValueProvider<>(parameterProvider::getParameterValue));
 	}
 
 	private <S> S populateProperties(ConversionContext context, RelationalPersistentEntity<S> entity,
@@ -641,6 +640,11 @@ private Object getPotentiallyConvertedSimpleWrite(Object value) {
 	protected Object getPotentiallyConvertedSimpleRead(Object value, TypeInformation<?> type) {
 
 		Class<?> target = type.getType();
+
+		if (getConversions().hasCustomReadTarget(value.getClass(), target)) {
+			return doConvert(value, target);
+		}
+
 		if (ClassUtils.isAssignableValue(target, value)) {
 			return value;
 		}
@@ -787,8 +791,7 @@ protected DefaultConversionContext(RelationalConverter sourceConverter,
 
 		@SuppressWarnings("unchecked")
 		@Override
-		public <S> S convert(Object source, TypeInformation<? extends S> typeHint,
-							 ConversionContext context) {
+		public <S> S convert(Object source, TypeInformation<? extends S> typeHint, ConversionContext context) {
 
 			Assert.notNull(source, "Source must not be null");
 			Assert.notNull(typeHint, "TypeInformation must not be null");
@@ -1196,7 +1199,8 @@ protected <T> T potentiallyConvertSpelValue(Object object, Parameter<T, Relation
 		}
 	}
 
-	private record PropertyTranslatingPropertyAccessor<T> (PersistentPropertyAccessor<T> delegate,
+	private record PropertyTranslatingPropertyAccessor<T>(
+			PersistentPropertyAccessor<T> delegate,
 			PersistentPropertyTranslator propertyTranslator) implements PersistentPropertyAccessor<T> {
 
 		static <T> PersistentPropertyAccessor<T> create(PersistentPropertyAccessor<T> delegate,

spring-data-relational/src/test/java/org/springframework/data/relational/core/conversion/MappingRelationalConverterUnitTests.java

@@ -17,6 +17,7 @@
 
 import static org.assertj.core.api.Assertions.*;
 
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.Date;
 import java.util.EnumSet;
@@ -26,13 +27,16 @@
 import java.util.Set;
 
 import org.junit.jupiter.api.Test;
+
 import org.springframework.beans.factory.annotation.Value;
+import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.annotation.Id;
 import org.springframework.data.annotation.PersistenceCreator;
 import org.springframework.data.convert.ConverterBuilder;
 import org.springframework.data.convert.ConverterBuilder.ConverterAware;
 import org.springframework.data.convert.CustomConversions;
 import org.springframework.data.convert.CustomConversions.StoreConversions;
+import org.springframework.data.convert.ReadingConverter;
 import org.springframework.data.mapping.model.SimpleTypeHolder;
 import org.springframework.data.projection.EntityProjection;
 import org.springframework.data.relational.core.mapping.Column;
@@ -83,6 +87,20 @@ void shouldEvaluateExpression() {
 		assertThat(result.name).isEqualTo("bar");
 	}
 
+	@Test
+		// GH-1689
+	void shouldApplySimpleTypeConverterSimpleType() {
+
+		converter = new MappingRelationalConverter(converter.getMappingContext(),
+				new CustomConversions(StoreConversions.NONE, List.of(MyEnumConverter.INSTANCE)));
+
+		RowDocument document = new RowDocument().append("my_enum", "one");
+
+		WithMyEnum result = converter.read(WithMyEnum.class, document);
+
+		assertThat(result.myEnum).isEqualTo(MyEnum.ONE);
+	}
+
 	@Test // GH-1586
 	void shouldReadNonstaticInner() {
 
@@ -328,4 +346,23 @@ interface AddressProjection {
 		String getStreet();
 	}
 
+	record WithMyEnum(MyEnum myEnum) {
+	}
+
+	enum MyEnum {
+		ONE, TWO,
+	}
+
+	@ReadingConverter
+	enum MyEnumConverter implements Converter<String, MyEnum> {
+
+		INSTANCE;
+
+		@Override
+		public MyEnum convert(String source) {
+			return MyEnum.valueOf(source.toUpperCase());
+		}
+
+	}
+
 }