#41 - Polishing.

Rename RowDataConverter to R2dbcConverters. Introduce R2dbcSimpleTypeHolder. Apply custom conversions check in MappingR2dbcConverter. Extend tests.

Original pull request: #65.

Author: mp911de

src/main/java/org/springframework/data/r2dbc/config/AbstractR2dbcConfiguration.java

@@ -17,7 +17,6 @@
 
 import io.r2dbc.spi.ConnectionFactory;
 
-import java.util.Collections;
 import java.util.Optional;
 
 import org.springframework.context.annotation.Bean;
@@ -153,7 +152,7 @@ public R2dbcCustomConversions r2dbcCustomConversions() {
 
 		Dialect dialect = getDialect(connectionFactory());
 		StoreConversions storeConversions = StoreConversions.of(dialect.getSimpleTypeHolder());
-		return new R2dbcCustomConversions(storeConversions, Collections.emptyList());
+		return new R2dbcCustomConversions(storeConversions, R2dbcCustomConversions.STORE_CONVERTERS);
 	}
 
 	/**

src/main/java/org/springframework/data/r2dbc/dialect/Dialect.java

@@ -3,6 +3,7 @@
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.Set;
 
 import org.springframework.data.mapping.model.SimpleTypeHolder;
 import org.springframework.data.r2dbc.dialect.ArrayColumns.Unsupported;
@@ -40,7 +41,11 @@ default Collection<? extends Class<?>> getSimpleTypes() {
 	 * @see #getSimpleTypes()
 	 */
 	default SimpleTypeHolder getSimpleTypeHolder() {
-		return new SimpleTypeHolder(new HashSet<>(getSimpleTypes()), true);
+
+		Set<Class<?>> simpleTypes = new HashSet<>(getSimpleTypes());
+		simpleTypes.addAll(R2dbcSimpleTypeHolder.R2DBC_SIMPLE_TYPES);
+
+		return new SimpleTypeHolder(simpleTypes, true);
 	}
 
 	/**

src/main/java/org/springframework/data/r2dbc/dialect/R2dbcSimpleTypeHolder.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2019 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
+ *
+ *      http://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.data.r2dbc.dialect;
+
+import io.r2dbc.spi.Row;
+
+import java.util.Collections;
+import java.util.Set;
+
+import org.springframework.data.mapping.model.SimpleTypeHolder;
+
+/**
+ * Simple constant holder for a {@link SimpleTypeHolder} enriched with R2DBC specific simple types.
+ *
+ * @author Mark Paluch
+ */
+public class R2dbcSimpleTypeHolder extends SimpleTypeHolder {
+
+	/**
+	 * Set of R2DBC simple types.
+	 */
+	public static final Set<Class<?>> R2DBC_SIMPLE_TYPES = Collections.singleton(Row.class);
+
+	public static final SimpleTypeHolder HOLDER = new R2dbcSimpleTypeHolder();
+
+	/**
+	 * Create a new {@link R2dbcSimpleTypeHolder} instance.
+	 */
+	private R2dbcSimpleTypeHolder() {
+		super(R2DBC_SIMPLE_TYPES, true);
+	}
+
+}

src/main/java/org/springframework/data/r2dbc/function/convert/MappingR2dbcConverter.java

@@ -42,6 +42,7 @@
 import org.springframework.data.relational.core.conversion.RelationalConverter;
 import org.springframework.data.relational.core.mapping.RelationalPersistentEntity;
 import org.springframework.data.relational.core.mapping.RelationalPersistentProperty;
+import org.springframework.data.util.ClassTypeInformation;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
@@ -61,7 +62,7 @@ public class MappingR2dbcConverter extends BasicRelationalConverter implements R
 	 */
 	public MappingR2dbcConverter(
 			MappingContext<? extends RelationalPersistentEntity<?>, ? extends RelationalPersistentProperty> context) {
-		super(context, new R2dbcCustomConversions(CustomConversions.StoreConversions.NONE, Collections.emptyList()));
+		super(context, new R2dbcCustomConversions(Collections.emptyList()));
 	}
 
 	/**
@@ -81,6 +82,19 @@ public MappingR2dbcConverter(
 
 	@Override
 	public <R> R read(Class<R> type, Row row) {
+
+		TypeInformation<? extends R> typeInfo = ClassTypeInformation.from(type);
+		Class<? extends R> rawType = typeInfo.getType();
+
+		if (Row.class.isAssignableFrom(rawType)) {
+			return type.cast(row);
+		}
+
+		if (getConversions().hasCustomReadTarget(Row.class, rawType)
+				|| getConversionService().canConvert(Row.class, rawType)) {
+			return getConversionService().convert(row, rawType);
+		}
+
 		return read(getRequiredPersistentEntity(type), row);
 	}
 

src/main/java/org/springframework/data/r2dbc/function/convert/R2dbcConverters.java

@@ -0,0 +1,233 @@
+/*
+ * Copyright 2019 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
+ *
+ *      http://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.data.r2dbc.function.convert;
+
+import io.r2dbc.spi.Row;
+
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.time.LocalTime;
+import java.time.OffsetDateTime;
+import java.time.ZonedDateTime;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.UUID;
+
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.core.convert.converter.ConverterFactory;
+import org.springframework.data.r2dbc.function.convert.R2dbcConverters.RowToNumberConverterFactory.RowToOffsetDateTimeConverter;
+import org.springframework.data.r2dbc.function.convert.R2dbcConverters.RowToNumberConverterFactory.RowToStringConverter;
+import org.springframework.data.r2dbc.function.convert.R2dbcConverters.RowToNumberConverterFactory.RowToUuidConverter;
+import org.springframework.data.r2dbc.function.convert.R2dbcConverters.RowToNumberConverterFactory.RowToZonedDateTimeConverter;
+import org.springframework.util.Assert;
+import org.springframework.util.NumberUtils;
+
+/**
+ * Wrapper class to contain useful converters for the usage with R2DBC.
+ *
+ * @author Hebert Coelho
+ * @author Mark Paluch
+ */
+abstract class R2dbcConverters {
+
+	private R2dbcConverters() {}
+
+	/**
+	 * @return A list of the registered converters
+	 */
+	public static Collection<Object> getConvertersToRegister() {
+
+		List<Object> converters = new ArrayList<>();
+
+		converters.add(RowToBooleanConverter.INSTANCE);
+		converters.add(RowToNumberConverterFactory.INSTANCE);
+		converters.add(RowToLocalDateConverter.INSTANCE);
+		converters.add(RowToLocalDateTimeConverter.INSTANCE);
+		converters.add(RowToLocalTimeConverter.INSTANCE);
+		converters.add(RowToOffsetDateTimeConverter.INSTANCE);
+		converters.add(RowToStringConverter.INSTANCE);
+		converters.add(RowToUuidConverter.INSTANCE);
+		converters.add(RowToZonedDateTimeConverter.INSTANCE);
+
+		return converters;
+	}
+
+	/**
+	 * Simple singleton to convert {@link Row}s to their {@link Boolean} representation.
+	 *
+	 * @author Hebert Coelho
+	 */
+	public enum RowToBooleanConverter implements Converter<Row, Boolean> {
+
+		INSTANCE;
+
+		@Override
+		public Boolean convert(Row row) {
+			return row.get(0, Boolean.class);
+		}
+	}
+
+	/**
+	 * Simple singleton to convert {@link Row}s to their {@link LocalDate} representation.
+	 *
+	 * @author Hebert Coelho
+	 */
+	public enum RowToLocalDateConverter implements Converter<Row, LocalDate> {
+
+		INSTANCE;
+
+		@Override
+		public LocalDate convert(Row row) {
+			return row.get(0, LocalDate.class);
+		}
+	}
+
+	/**
+	 * Simple singleton to convert {@link Row}s to their {@link LocalDateTime} representation.
+	 *
+	 * @author Hebert Coelho
+	 */
+	public enum RowToLocalDateTimeConverter implements Converter<Row, LocalDateTime> {
+
+		INSTANCE;
+
+		@Override
+		public LocalDateTime convert(Row row) {
+			return row.get(0, LocalDateTime.class);
+		}
+	}
+
+	/**
+	 * Simple singleton to convert {@link Row}s to their {@link LocalTime} representation.
+	 *
+	 * @author Hebert Coelho
+	 */
+	public enum RowToLocalTimeConverter implements Converter<Row, LocalTime> {
+
+		INSTANCE;
+
+		@Override
+		public LocalTime convert(Row row) {
+			return row.get(0, LocalTime.class);
+		}
+	}
+
+	/**
+	 * Singleton converter factory to convert the first column of a {@link Row} to a {@link Number}.
+	 * <p>
+	 * Support Number classes including Byte, Short, Integer, Float, Double, Long, BigInteger, BigDecimal. This class
+	 * delegates to {@link NumberUtils#convertNumberToTargetClass(Number, Class)} to perform the conversion.
+	 *
+	 * @see Byte
+	 * @see Short
+	 * @see Integer
+	 * @see Long
+	 * @see java.math.BigInteger
+	 * @see Float
+	 * @see Double
+	 * @see java.math.BigDecimal
+	 * @author Hebert Coelho
+	 */
+	public enum RowToNumberConverterFactory implements ConverterFactory<Row, Number> {
+
+		INSTANCE;
+
+		@Override
+		public <T extends Number> Converter<Row, T> getConverter(Class<T> targetType) {
+			Assert.notNull(targetType, "Target type must not be null");
+			return new RowToNumber<>(targetType);
+		}
+
+		static class RowToNumber<T extends Number> implements Converter<Row, T> {
+
+			private final Class<T> targetType;
+
+			RowToNumber(Class<T> targetType) {
+				this.targetType = targetType;
+			}
+
+			@Override
+			public T convert(Row source) {
+
+				Object object = source.get(0, targetType);
+
+				return (object != null ? NumberUtils.convertNumberToTargetClass((Number) object, this.targetType) : null);
+			}
+		}
+
+		/**
+		 * Simple singleton to convert {@link Row}s to their {@link OffsetDateTime} representation.
+		 *
+		 * @author Hebert Coelho
+		 */
+		public enum RowToOffsetDateTimeConverter implements Converter<Row, OffsetDateTime> {
+
+			INSTANCE;
+
+			@Override
+			public OffsetDateTime convert(Row row) {
+				return row.get(0, OffsetDateTime.class);
+			}
+		}
+
+		/**
+		 * Simple singleton to convert {@link Row}s to their {@link String} representation.
+		 *
+		 * @author Hebert Coelho
+		 */
+		public enum RowToStringConverter implements Converter<Row, String> {
+
+			INSTANCE;
+
+			@Override
+			public String convert(Row row) {
+				return row.get(0, String.class);
+			}
+		}
+
+		/**
+		 * Simple singleton to convert {@link Row}s to their {@link UUID} representation.
+		 *
+		 * @author Hebert Coelho
+		 */
+		public enum RowToUuidConverter implements Converter<Row, UUID> {
+
+			INSTANCE;
+
+			@Override
+			public UUID convert(Row row) {
+				return row.get(0, UUID.class);
+			}
+		}
+
+		/**
+		 * Simple singleton to convert {@link Row}s to their {@link ZonedDateTime} representation.
+		 *
+		 * @author Hebert Coelho
+		 */
+		public enum RowToZonedDateTimeConverter implements Converter<Row, ZonedDateTime> {
+
+			INSTANCE;
+
+			@Override
+			public ZonedDateTime convert(Row row) {
+				return row.get(0, ZonedDateTime.class);
+			}
+		}
+	}
+}