DATAREDIS-849 - Add support for immutable objects.

We now support immutable objects for saving (e.g. object without a provided Id) and loading (i.e. persistence constructor declares a subset of properties). New instances are created using wither methods/Kotlin copy(…) methods if an immutable object requires association with an Id.

Association of the Id to its object moved from RedisKeyValueAdapter to RedisKeyValueTemplate.

src/main/java/org/springframework/data/redis/core/RedisKeyValueAdapter.java

@@ -36,7 +36,7 @@ import org.springframework.core.convert.ConversionService;
 import org.springframework.core.convert.ConverterNotFoundException;
 import org.springframework.data.keyvalue.core.AbstractKeyValueAdapter;
 import org.springframework.data.keyvalue.core.KeyValueAdapter;
-import org.springframework.data.keyvalue.core.mapping.KeyValuePersistentProperty;
+import org.springframework.data.mapping.PersistentPropertyAccessor;
 import org.springframework.data.redis.connection.DataType;
 import org.springframework.data.redis.connection.Message;
 import org.springframework.data.redis.connection.MessageListener;
@@ -217,15 +217,7 @@ public class RedisKeyValueAdapter extends AbstractKeyValueAdapter
 		}
 
 		if (rdo.getId() == null) {
-
 			rdo.setId(converter.getConversionService().convert(id, String.class));
-
-			if (!(item instanceof RedisData)) {
-				KeyValuePersistentProperty idProperty = converter.getMappingContext()
-						.getRequiredPersistentEntity(item.getClass()).getRequiredIdProperty();
-				converter.getMappingContext().getRequiredPersistentEntity(item.getClass()).getPropertyAccessor(item)
-						.setProperty(idProperty, id);
-			}
 		}
 
 		redisOps.execute((RedisCallback<Object>) connection -> {
@@ -624,8 +616,13 @@ public class RedisKeyValueAdapter extends AbstractKeyValueAdapter
 			});
 
 			if (timeout != null || !ttlProperty.getType().isPrimitive()) {
-				entity.getPropertyAccessor(target).setProperty(ttlProperty,
+
+				PersistentPropertyAccessor<T> propertyAccessor = entity.getPropertyAccessor(target);
+
+				propertyAccessor.setProperty(ttlProperty,
 						converter.getConversionService().convert(timeout, ttlProperty.getType()));
+
+				target = propertyAccessor.getBean();
 			}
 		}
 

src/main/java/org/springframework/data/redis/core/RedisKeyValueTemplate.java

@@ -22,8 +22,12 @@ import java.util.List;
 import org.springframework.data.keyvalue.core.KeyValueAdapter;
 import org.springframework.data.keyvalue.core.KeyValueCallback;
 import org.springframework.data.keyvalue.core.KeyValueTemplate;
+import org.springframework.data.keyvalue.core.mapping.KeyValuePersistentProperty;
+import org.springframework.data.mapping.PersistentPropertyAccessor;
 import org.springframework.data.redis.core.convert.RedisConverter;
+import org.springframework.data.redis.core.convert.RedisData;
 import org.springframework.data.redis.core.mapping.RedisMappingContext;
+import org.springframework.data.redis.core.mapping.RedisPersistentEntity;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
 
@@ -127,14 +131,31 @@ public class RedisKeyValueTemplate extends KeyValueTemplate {
 	 * @see org.springframework.data.keyvalue.core.KeyValueTemplate#insert(java.lang.Object, java.lang.Object)
 	 */
 	@Override
-	public void insert(Object id, Object objectToInsert) {
+	public <T> T insert(Object id, T objectToInsert) {
 
 		if (objectToInsert instanceof PartialUpdate) {
 			doPartialUpdate((PartialUpdate<?>) objectToInsert);
-			return;
+			return objectToInsert;
 		}
 
-		super.insert(id, objectToInsert);
+		if (!(objectToInsert instanceof RedisData)) {
+
+			RedisConverter converter = adapter.getConverter();
+
+			RedisPersistentEntity<?> entity = converter.getMappingContext()
+					.getRequiredPersistentEntity(objectToInsert.getClass());
+
+			KeyValuePersistentProperty idProperty = entity.getRequiredIdProperty();
+			PersistentPropertyAccessor<T> propertyAccessor = entity.getPropertyAccessor(objectToInsert);
+
+			if (propertyAccessor.getProperty(idProperty) == null) {
+
+				propertyAccessor.setProperty(idProperty, id);
+				return super.insert(id, propertyAccessor.getBean());
+			}
+		}
+
+		return super.insert(id, objectToInsert);
 	}
 
 	/*
@@ -142,14 +163,20 @@ public class RedisKeyValueTemplate extends KeyValueTemplate {
 	 * @see org.springframework.data.keyvalue.core.KeyValueTemplate#update(java.lang.Object)
 	 */
 	@Override
-	public void update(Object objectToUpdate) {
+	public <T> T update(T objectToUpdate) {
 
 		if (objectToUpdate instanceof PartialUpdate) {
 			doPartialUpdate((PartialUpdate<?>) objectToUpdate);
-			return;
+
+			return objectToUpdate;
 		}
 
-		super.update(objectToUpdate);
+		return super.update(objectToUpdate);
+	}
+
+	@Override
+	public <T> T update(Object id, T objectToUpdate) {
+		return super.update(id, objectToUpdate);
 	}
 
 	protected void doPartialUpdate(final PartialUpdate<?> update) {

src/main/java/org/springframework/data/redis/core/convert/MappingRedisConverter.java

@@ -211,7 +211,11 @@ public class MappingRedisConverter implements RedisConverter, InitializingBean {
 			R instance = (R) conversionService.convert(partial, readType.getType());
 
 			if (entity != null && entity.hasIdProperty()) {
-				entity.getPropertyAccessor(instance).setProperty(entity.getRequiredIdProperty(), source.getId());
+
+				PersistentPropertyAccessor<R> propertyAccessor = entity.getPropertyAccessor(instance);
+
+				propertyAccessor.setProperty(entity.getRequiredIdProperty(), source.getId());
+				instance = propertyAccessor.getBean();
 			}
 			return instance;
 		}
@@ -246,7 +250,7 @@ public class MappingRedisConverter implements RedisConverter, InitializingBean {
 
 		readAssociation(path, source, entity, accessor);
 
-		return (R) instance;
+		return (R) accessor.getBean();
 	}
 
 	@SuppressWarnings("unchecked")