org.springframework.jdbc.core.ResultSetExtractor Maven / Gradle / Ivy
/*
* Copyright 2002-2004 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.ResultSet;
import java.sql.SQLException;
import org.springframework.dao.DataAccessException;
/**
* Callback interface used by JdbcTemplate's query methods.
* Implementations of this interface perform the actual work of extracting
* results, but don't need to worry about exception handling. SQLExceptions
* will be caught and handled correctly by the JdbcTemplate class.
*
* This interface is mainly used within the JDBC framework.
* A RowCallbackHandler is usually a simpler choice for ResultSet processing,
* in particular a RowMapperResultReader in combination with a RowMapper.
*
*
Note: In contrast to a RowCallbackHandler, a ResultSetExtractor object
* is typically stateless and thus reusable, as long as it doesn't access
* stateful resources (like output streams when streaming LOB contents)
* or keep result state within the object.
*
* @author Rod Johnson
* @since April 24, 2003
* @see JdbcTemplate
* @see RowCallbackHandler
* @see RowMapperResultReader
* @see org.springframework.jdbc.core.support.AbstractLobStreamingResultSetExtractor
*/
public interface ResultSetExtractor {
/**
* Implementations must implement this method to process
* all rows in the ResultSet.
* @param rs ResultSet to extract data from. Implementations should
* not close this: it will be closed by the JdbcTemplate.
* @return an arbitrary result object, or null if none
* (the extractor will typically be stateful in the latter case).
* @throws SQLException if a SQLException is encountered getting column
* values or navigating (that is, there's no need to catch SQLException)
* @throws DataAccessException in case of custom exceptions
*/
Object extractData(ResultSet rs) throws SQLException, DataAccessException;
}