com.datastax.oss.driver.api.mapper.entity.saving.NullSavingStrategy Maven / Gradle / Ivy
/*
* Copyright DataStax, Inc.
*
* 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 com.datastax.oss.driver.api.mapper.entity.saving;
import com.datastax.oss.driver.api.core.DefaultProtocolVersion;
import com.datastax.oss.driver.api.core.cql.BoundStatement;
import com.datastax.oss.driver.api.mapper.MapperException;
import com.datastax.oss.driver.api.mapper.annotations.Entity;
/** Defines how null {@link Entity} properties will be handled during data insertion. */
public enum NullSavingStrategy {
/**
* Do not insert null properties.
*
* In other words, the mapper won't call the corresponding setter on the {@link
* BoundStatement}. The generated code looks approximately like this:
*
*
* if (entity.getDescription() != null) {
* boundStatement = boundStatement.setString("description", entity.getDescription());
* }
*
*
* This avoids inserting tombstones for null properties. On the other hand, if the query is an
* update and the column previously had another value, it won't be overwritten.
*
* Note that unset values are only supported with {@link DefaultProtocolVersion#V4 native
* protocol v4} (Cassandra 2.2) or above. If you try to use this strategy with a lower Cassandra
* version, the mapper will throw a {@link MapperException} when you try to build the
* corresponding DAO.
*
* @see CASSANDRA-7304
*/
DO_NOT_SET,
/**
* Insert null properties as a CQL {@code NULL}.
*
*
In other words, the mapper will always call the corresponding setter on the {@link
* BoundStatement}. The generated code looks approximately like this:
*
*
* // Called even if entity.getDescription() == null
* boundStatement = boundStatement.setString("description", entity.getDescription());
*
*/
SET_TO_NULL
}