001/*
002 * Copyright 2002-2016 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.jdbc.core;
018
019import java.sql.Connection;
020import java.sql.SQLException;
021
022import org.springframework.dao.DataAccessException;
023
024/**
025 * Generic callback interface for code that operates on a JDBC Connection.
026 * Allows to execute any number of operations on a single Connection,
027 * using any type and number of Statements.
028 *
029 * <p>This is particularly useful for delegating to existing data access code
030 * that expects a Connection to work on and throws SQLException. For newly
031 * written code, it is strongly recommended to use JdbcTemplate's more specific
032 * operations, for example a {@code query} or {@code update} variant.
033 *
034 * @author Juergen Hoeller
035 * @since 1.1.3
036 * @see JdbcTemplate#execute(ConnectionCallback)
037 * @see JdbcTemplate#query
038 * @see JdbcTemplate#update
039 */
040public interface ConnectionCallback<T> {
041
042        /**
043         * Gets called by {@code JdbcTemplate.execute} with an active JDBC
044         * Connection. Does not need to care about activating or closing the
045         * Connection, or handling transactions.
046         * <p>If called without a thread-bound JDBC transaction (initiated by
047         * DataSourceTransactionManager), the code will simply get executed on the
048         * JDBC connection with its transactional semantics. If JdbcTemplate is
049         * configured to use a JTA-aware DataSource, the JDBC Connection and thus
050         * the callback code will be transactional if a JTA transaction is active.
051         * <p>Allows for returning a result object created within the callback, i.e.
052         * a domain object or a collection of domain objects. Note that there's special
053         * support for single step actions: see {@code JdbcTemplate.queryForObject}
054         * etc. A thrown RuntimeException is treated as application exception:
055         * it gets propagated to the caller of the template.
056         * @param con active JDBC Connection
057         * @return a result object, or {@code null} if none
058         * @throws SQLException if thrown by a JDBC method, to be auto-converted
059         * to a DataAccessException by a SQLExceptionTranslator
060         * @throws DataAccessException in case of custom exceptions
061         * @see JdbcTemplate#queryForObject(String, Class)
062         * @see JdbcTemplate#queryForRowSet(String)
063         */
064        T doInConnection(Connection con) throws SQLException, DataAccessException;
065
066}