DATAJDBC-102 - Determine the EntityInstantiator to be used dynamically.

Replaced the direct use of EntityInstantiator with EntityInstantiators.
Moved it into the MappingContext because instantiation is part of the mapping process.

Author: schauder

src/main/java/org/springframework/data/jdbc/core/EntityRowMapper.java

@@ -23,8 +23,7 @@
 
 import org.springframework.core.convert.ConversionService;
 import org.springframework.core.convert.converter.Converter;
-import org.springframework.data.convert.ClassGeneratingEntityInstantiator;
-import org.springframework.data.convert.EntityInstantiator;
+import org.springframework.data.convert.EntityInstantiators;
 import org.springframework.data.jdbc.mapping.model.JdbcMappingContext;
 import org.springframework.data.jdbc.mapping.model.JdbcPersistentEntity;
 import org.springframework.data.jdbc.mapping.model.JdbcPersistentProperty;
@@ -35,8 +34,6 @@
 import org.springframework.data.mapping.model.ConvertingPropertyAccessor;
 import org.springframework.data.mapping.model.ParameterValueProvider;
 import org.springframework.jdbc.core.RowMapper;
-import org.springframework.lang.Nullable;
-import org.springframework.util.Assert;
 
 /**
  * Maps a ResultSet to an entity of type {@code T}, including entities referenced.
@@ -50,7 +47,7 @@ public class EntityRowMapper<T> implements RowMapper<T> {
 	private static final Converter ITERABLE_OF_ENTRY_TO_MAP_CONVERTER = new IterableOfEntryToMapConverter();
 
 	private final JdbcPersistentEntity<T> entity;
-	private final EntityInstantiator instantiator = new ClassGeneratingEntityInstantiator();
+
 	private final ConversionService conversions;
 	private final JdbcMappingContext context;
 	private final DataAccessStrategy accessStrategy;
@@ -98,17 +95,17 @@ public T mapRow(ResultSet resultSet, int rowNumber) throws SQLException {
 	}
 
 	private T createInstance(ResultSet rs) {
-		return instantiator.createInstance(entity, new ResultSetParameterValueProvider(rs, entity, conversions, ""));
-	}
 
+		return context.getInstantiatorFor(entity) //
+				.createInstance(entity, new ResultSetParameterValueProvider(rs, entity, conversions, ""));
+	}
 
 	/**
 	 * Read a single value or a complete Entity from the {@link ResultSet} passed as an argument.
 	 *
 	 * @param resultSet the {@link ResultSet} to extract the value from. Must not be {@code null}.
 	 * @param property the {@link JdbcPersistentProperty} for which the value is intended. Must not be {@code null}.
 	 * @param prefix to be used for all column names accessed by this method. Must not be {@code null}.
-	 *
 	 * @return the value read from the {@link ResultSet}. May be {@code null}.
 	 */
 	private Object readFrom(ResultSet resultSet, JdbcPersistentProperty property, String prefix) {
@@ -138,8 +135,8 @@ private <S> S readEntityFrom(ResultSet rs, PersistentProperty<?> property) {
 			return null;
 		}
 
-		S instance = instantiator.createInstance(entity,
-				new ResultSetParameterValueProvider(rs, entity, conversions, prefix));
+		S instance = context.getInstantiatorFor(entity) //
+				.createInstance(entity, new ResultSetParameterValueProvider(rs, entity, conversions, prefix));
 
 		PersistentPropertyAccessor accessor = entity.getPropertyAccessor(instance);
 		ConvertingPropertyAccessor propertyAccessor = new ConvertingPropertyAccessor(accessor, conversions);

src/main/java/org/springframework/data/jdbc/mapping/model/JdbcMappingContext.java

@@ -27,10 +27,14 @@
 import java.util.HashSet;
 import java.util.List;
 
+import lombok.Setter;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.core.convert.support.DefaultConversionService;
 import org.springframework.core.convert.support.GenericConversionService;
+import org.springframework.data.convert.EntityInstantiator;
+import org.springframework.data.convert.EntityInstantiators;
 import org.springframework.data.convert.Jsr310Converters;
+import org.springframework.data.mapping.PersistentEntity;
 import org.springframework.data.mapping.PropertyPath;
 import org.springframework.data.mapping.context.AbstractMappingContext;
 import org.springframework.data.mapping.context.MappingContext;
@@ -59,6 +63,8 @@ public class JdbcMappingContext extends AbstractMappingContext<JdbcPersistentEnt
 	@Getter private final NamedParameterJdbcOperations template;
 	@Getter private SimpleTypeHolder simpleTypeHolder;
 	private GenericConversionService conversions = getDefaultConversionService();
+	@Setter
+	private EntityInstantiators instantiators = new EntityInstantiators();
 
 	public JdbcMappingContext(NamingStrategy namingStrategy, NamedParameterJdbcOperations template,
 			ConversionCustomizer customizer) {
@@ -130,6 +136,10 @@ public ConversionService getConversions() {
 		return conversions;
 	}
 
+	public EntityInstantiator getInstantiatorFor(PersistentEntity<?, ?> entity) {
+		return instantiators.getInstantiatorFor(entity);
+	}
+
 	private static GenericConversionService getDefaultConversionService() {
 
 		DefaultConversionService conversionService = new DefaultConversionService();