/*
* Copyright 2002-2008 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
*
* 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 org.springframework.jdbc.core;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import org.springframework.dao.DataAccessException;
/**
* Generic callback interface for code that operates on a PreparedStatement.
* Allows to execute any number of operations on a single PreparedStatement,
* for example a single <code>executeUpdate</code> call or repeated
* <code>executeUpdate</code> calls with varying parameters.
*
* <p>Used internally by JdbcTemplate, but also useful for application code.
* Note that the passed-in PreparedStatement can have been created by the
* framework or by a custom PreparedStatementCreator. However, the latter is
* hardly ever necessary, as most custom callback actions will perform updates
* in which case a standard PreparedStatement is fine. Custom actions will
* always set parameter values themselves, so that PreparedStatementCreator
* capability is not needed either.
*
* @author Juergen Hoeller
* @since 16.03.2004
* @see JdbcTemplate#execute(String, PreparedStatementCallback)
* @see JdbcTemplate#execute(PreparedStatementCreator, PreparedStatementCallback)
*/
public interface PreparedStatementCallback<T> {
/**
* Gets called by <code>JdbcTemplate.execute</code> with an active JDBC
* PreparedStatement. Does not need to care about closing the Statement
* or the Connection, or about handling transactions: this will all be
* handled by Spring's JdbcTemplate.
*
* <p><b>NOTE:</b> Any ResultSets opened should be closed in finally blocks
* within the callback implementation. Spring will close the Statement
* object after the callback returned, but this does not necessarily imply
* that the ResultSet resources will be closed: the Statement objects might
* get pooled by the connection pool, with <code>close</code> calls only
* returning the object to the pool but not physically closing the resources.
*
* <p>If called without a thread-bound JDBC transaction (initiated by
* DataSourceTransactionManager), the code will simply get executed on the
* JDBC connection with its transactional semantics. If JdbcTemplate is
* configured to use a JTA-aware DataSource, the JDBC connection and thus
* the callback code will be transactional if a JTA transaction is active.
*
* <p>Allows for returning a result object created within the callback, i.e.
* a domain object or a collection of domain objects. Note that there's
* special support for single step actions: see JdbcTemplate.queryForObject etc.
* A thrown RuntimeException is treated as application exception, it gets
* propagated to the caller of the template.
*
* @param ps active JDBC PreparedStatement
* @return a result object, or <code>null</code> if none
* @throws SQLException if thrown by a JDBC method, to be auto-converted
* to a DataAccessException by a SQLExceptionTranslator
* @throws DataAccessException in case of custom exceptions
* @see JdbcTemplate#queryForObject(String, Object[], Class)
* @see JdbcTemplate#queryForList(String, Object[])
*/
T doInPreparedStatement(PreparedStatement ps) throws SQLException, DataAccessException;
}
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