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/* * Copyright 2016-2019 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 * * https://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.cassandra.core; import java.util.Iterator; import java.util.List; import java.util.stream.Stream; import org.springframework.dao.DataAccessException; import org.springframework.data.cassandra.core.convert.CassandraConverter; import org.springframework.data.cassandra.core.cql.CqlIdentifier; import org.springframework.data.cassandra.core.cql.CqlOperations; import org.springframework.data.cassandra.core.cql.QueryOptions; import org.springframework.data.cassandra.core.cql.WriteOptions; import org.springframework.data.cassandra.core.query.CassandraPageRequest; import org.springframework.data.cassandra.core.query.Query; import org.springframework.data.cassandra.core.query.Update; import org.springframework.data.domain.Slice; import org.springframework.lang.Nullable; import com.datastax.driver.core.Statement; /** * Interface specifying a basic set of Cassandra operations. Implemented by {@link CassandraTemplate}. Not often used * directly, but a useful option to enhance testability, as it can easily be mocked or stubbed. * * @author Alex Shvid * @author David Webb * @author Matthew Adams * @author Mark Paluch * @see CassandraTemplate * @see CqlOperations * @see Statement * @see InsertOptions * @see UpdateOptions */ public interface CassandraOperations extends FluentCassandraOperations { /** * Returns a new {@link CassandraBatchOperations}. Each {@link CassandraBatchOperations} instance can be executed only * once so you might want to obtain new {@link CassandraBatchOperations} instances for each batch. * * @return a new {@link CassandraBatchOperations} associated with the given entity class. */ CassandraBatchOperations batchOps(); /** * Returns the underlying {@link CassandraConverter}. * * @return the underlying {@link CassandraConverter}. */ CassandraConverter getConverter(); /** * Expose the underlying {@link CqlOperations} to allow CQL operations. * * @return the underlying {@link CqlOperations}. * @see CqlOperations */ CqlOperations getCqlOperations(); /** * The table name used for the specified class by this template. * * @param entityClass The entity type must not be {@literal null}. * @return the {@link CqlIdentifier} */ CqlIdentifier getTableName(Class<?> entityClass); // ------------------------------------------------------------------------- // Methods dealing with static CQL // ------------------------------------------------------------------------- /** * Execute a {@code SELECT} query and convert the resulting items to a {@link List} of entities. * * @param cql must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @return the converted results * @throws DataAccessException if there is any problem executing the query. */ <T> List<T> select(String cql, Class<T> entityClass) throws DataAccessException; /** * Execute a {@code SELECT} query and convert the resulting items to a {@link Iterator} of entities. * <p> * Returns a {@link Iterator} that wraps the Cassandra {@link com.datastax.driver.core.ResultSet}. * * @param <T> element return type. * @param cql query to execute. Must not be empty or {@literal null}. * @param entityClass Class type of the elements in the {@link Iterator} stream. Must not be {@literal null}. * @return an {@link Iterator} (stream) over the elements in the query result set. * @throws DataAccessException if there is any problem executing the query. * @since 1.5 */ <T> Stream<T> stream(String cql, Class<T> entityClass) throws DataAccessException; /** * Execute a {@code SELECT} query and convert the resulting item to an entity. * * @param cql must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @return the converted object or {@literal null}. * @throws DataAccessException if there is any problem executing the query. */ @Nullable <T> T selectOne(String cql, Class<T> entityClass) throws DataAccessException; // ------------------------------------------------------------------------- // Methods dealing with com.datastax.driver.core.Statement // ------------------------------------------------------------------------- /** * Execute a {@code SELECT} query and convert the resulting items to a {@link List} of entities. * * @param statement must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @return the converted results * @throws DataAccessException if there is any problem executing the query. */ <T> List<T> select(Statement statement, Class<T> entityClass) throws DataAccessException; /** * Execute a {@code SELECT} query with paging and convert the result set to a {@link Slice} of entities. A sliced * query translates the effective {@link Statement#getFetchSize() fetch size} to the page size. * * @param statement the CQL statement, must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @return the converted results * @throws DataAccessException if there is any problem executing the query. * @since 2.0 */ <T> Slice<T> slice(Statement statement, Class<T> entityClass) throws DataAccessException; /** * Execute a {@code SELECT} query and convert the resulting items to a {@link Iterator} of entities. * <p> * Returns a {@link Iterator} that wraps the Cassandra {@link com.datastax.driver.core.ResultSet}. * * @param <T> element return type. * @param statement query to execute. Must not be empty or {@literal null}. * @param entityClass Class type of the elements in the {@link Iterator} stream. Must not be {@literal null}. * @return an {@link Iterator} (stream) over the elements in the query result set. * @throws DataAccessException if there is any problem executing the query. * @since 1.5 */ <T> Stream<T> stream(Statement statement, Class<T> entityClass) throws DataAccessException; /** * Execute a {@code SELECT} query and convert the resulting item to an entity. * * @param statement must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @return the converted object or {@literal null}. * @throws DataAccessException if there is any problem executing the query. */ @Nullable <T> T selectOne(Statement statement, Class<T> entityClass) throws DataAccessException; // ------------------------------------------------------------------------- // Methods dealing with org.springframework.data.cassandra.core.query.Query // ------------------------------------------------------------------------- /** * Execute a {@code SELECT} query and convert the resulting items to a {@link List} of entities. * * @param query must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @return the converted results * @throws DataAccessException if there is any problem executing the query. * @since 2.0 */ <T> List<T> select(Query query, Class<T> entityClass) throws DataAccessException; /** * Execute a {@code SELECT} query with paging and convert the result set to a {@link Slice} of entities. * * @param query the query object used to create a CQL statement, must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @return the converted results * @throws DataAccessException if there is any problem executing the query. * @since 2.0 * @see CassandraPageRequest */ <T> Slice<T> slice(Query query, Class<T> entityClass) throws DataAccessException; /** * Execute a {@code SELECT} query and convert the resulting items to a {@link Iterator} of entities. * <p> * Returns a {@link Iterator} that wraps the Cassandra {@link com.datastax.driver.core.ResultSet}. * * @param <T> element return type. * @param query query to execute. Must not be empty or {@literal null}. * @param entityClass Class type of the elements in the {@link Iterator} stream. Must not be {@literal null}. * @return an {@link Iterator} (stream) over the elements in the query result set. * @throws DataAccessException if there is any problem executing the query. * @since 2.0 */ <T> Stream<T> stream(Query query, Class<T> entityClass) throws DataAccessException; /** * Execute a {@code SELECT} query and convert the resulting item to an entity. * * @param query must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @return the converted object or {@literal null}. * @throws DataAccessException if there is any problem executing the query. * @since 2.0 */ @Nullable <T> T selectOne(Query query, Class<T> entityClass) throws DataAccessException; /** * Update the queried entities and return {@literal true} if the update was applied. * * @param query must not be {@literal null}. * @param update must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @throws DataAccessException if there is any problem executing the query. */ boolean update(Query query, Update update, Class<?> entityClass) throws DataAccessException; /** * Remove entities (rows)/columns from the table by {@link Query}. * * @param query must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @throws DataAccessException if there is any problem executing the query. */ boolean delete(Query query, Class<?> entityClass) throws DataAccessException; // ------------------------------------------------------------------------- // Methods dealing with entities // ------------------------------------------------------------------------- /** * Returns the number of rows for the given entity class. * * @param entityClass {@link Class type} of the entity; must not be {@literal null}. * @return the number of existing entities. * @throws DataAccessException if any problem occurs while executing the query. */ long count(Class<?> entityClass) throws DataAccessException; /** * Returns the number of rows for the given entity class applying {@link Query}. This overridden method allows users * to further refine the selection criteria using a {@link Query} predicate to determine how many entities of the * given {@link Class type} match the criteria. * * @param query user-defined count {@link Query} to execute; must not be {@literal null}. * @param entityClass {@link Class type} of the entity; must not be {@literal null}. * @return the number of existing entities. * @throws DataAccessException if any problem occurs while executing the query. * @since 2.1 */ long count(Query query, Class<?> entityClass) throws DataAccessException; /** * Determine whether a row of {@code entityClass} with the given {@code id} exists. * * @param id Id value. For single primary keys it's the plain value. For composite primary keys either, it's an * instance of either {@link org.springframework.data.cassandra.core.mapping.PrimaryKeyClass} or * {@link org.springframework.data.cassandra.core.mapping.MapId}. Must not be {@literal null}. * @param entityClass {@link Class type} of the entity; must not be {@literal null}. * @return {@literal true} if the object exists. * @throws DataAccessException if any problem occurs while executing the query. */ boolean exists(Object id, Class<?> entityClass) throws DataAccessException; /** * Determine whether the result for {@code entityClass} {@link Query} yields at least one row. * * @param query user-defined exists {@link Query} to execute; must not be {@literal null}. * @param entityClass {@link Class type} of the entity; must not be {@literal null}. * @return {@literal true} if the object exists. * @throws DataAccessException if any problem occurs while executing the query. * @since 2.1 */ boolean exists(Query query, Class<?> entityClass) throws DataAccessException; /** * Execute the Select by {@code id} for the given {@code entityClass}. * * @param id the Id value. For single primary keys it's the plain value. For composite primary keys either the * {@link org.springframework.data.cassandra.core.mapping.PrimaryKeyClass} or * {@link org.springframework.data.cassandra.core.mapping.MapId}. Must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @return the converted object or {@literal null}. * @throws DataAccessException if there is any problem executing the query. */ @Nullable <T> T selectOneById(Object id, Class<T> entityClass) throws DataAccessException; /** * Insert the given entity and return the entity if the insert was applied. * * @param entity The entity to insert, must not be {@literal null}. * @return the inserted entity. * @throws DataAccessException if there is any problem executing the query. */ <T> T insert(T entity) throws DataAccessException; /** * Insert the given entity applying {@link WriteOptions} and return the entity if the insert was applied. * * @param entity The entity to insert, must not be {@literal null}. * @param options must not be {@literal null}. * @return the {@link EntityWriteResult} for this operation. * @throws DataAccessException if there is any problem executing the query. * @see InsertOptions#empty() */ <T> EntityWriteResult<T> insert(T entity, InsertOptions options) throws DataAccessException; /** * Update the given entity and return the entity if the update was applied. * * @param entity The entity to update, must not be {@literal null}. * @return the updated entity. * @throws DataAccessException if there is any problem executing the query. */ <T> T update(T entity) throws DataAccessException; /** * Update the given entity applying {@link WriteOptions} and return the entity if the update was applied. * * @param entity The entity to update, must not be {@literal null}. * @param options must not be {@literal null}. * @return the {@link EntityWriteResult} for this operation. * @throws DataAccessException if there is any problem executing the query. * @see UpdateOptions#empty() */ <T> EntityWriteResult<T> update(T entity, UpdateOptions options) throws DataAccessException; /** * Delete the given entity and return the entity if the delete was applied. * * @param entity must not be {@literal null}. * @throws DataAccessException if there is any problem executing the query. */ void delete(Object entity) throws DataAccessException; /** * Delete the given entity applying {@link QueryOptions} and return the entity if the delete was applied. * * @param entity must not be {@literal null}. * @param options must not be {@literal null}. * @return the {@link WriteResult} for this operation. * @throws DataAccessException if there is any problem executing the query. * @see QueryOptions#empty() */ WriteResult delete(Object entity, QueryOptions options) throws DataAccessException; /** * Delete the given entity applying {@link DeleteOptions} and return the entity if the delete was applied. * * @param entity must not be {@literal null}. * @param options must not be {@literal null}. * @return the {@link WriteResult} for this operation. * @throws DataAccessException if there is any problem executing the query. * @see DeleteOptions#empty() * @since 2.2 */ default WriteResult delete(Object entity, DeleteOptions options) throws DataAccessException { return delete(entity, (QueryOptions) options); } /** * Remove the given object from the table by id. * * @param id the Id value. For single primary keys it's the plain value. For composite primary keys either the * {@link org.springframework.data.cassandra.core.mapping.PrimaryKeyClass} or * {@link org.springframework.data.cassandra.core.mapping.MapId}. Must not be {@literal null}. * @param entityClass The entity type must not be {@literal null}. * @throws DataAccessException if there is any problem executing the query. */ boolean deleteById(Object id, Class<?> entityClass) throws DataAccessException; /** * Execute a {@code TRUNCATE} query to remove all entities of a given class. * * @param entityClass The entity type must not be {@literal null}. * @throws DataAccessException if there is any problem executing the query. */ void truncate(Class<?> entityClass) throws DataAccessException; }