org.springframework.jdbc.core.RowCallbackHandler Maven / Gradle / Ivy
/*
* Copyright 2002-2016 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.jdbc.core;
import java.sql.ResultSet;
import java.sql.SQLException;
/**
* An interface used by {@link JdbcTemplate} for processing rows of a
* {@link java.sql.ResultSet} on a per-row basis. Implementations of
* this interface perform the actual work of processing each row
* but don't need to worry about exception handling.
* {@link java.sql.SQLException SQLExceptions} will be caught and handled
* by the calling JdbcTemplate.
*
* In contrast to a {@link ResultSetExtractor}, a RowCallbackHandler
* object is typically stateful: It keeps the result state within the
* object, to be available for later inspection. See
* {@link RowCountCallbackHandler} for a usage example.
*
*
Consider using a {@link RowMapper} instead if you need to map
* exactly one result object per row, assembling them into a List.
*
* @author Rod Johnson
* @author Juergen Hoeller
* @see JdbcTemplate
* @see RowMapper
* @see ResultSetExtractor
* @see RowCountCallbackHandler
*/
@FunctionalInterface
public interface RowCallbackHandler {
/**
* Implementations must implement this method to process each row of data
* in the ResultSet. This method should not call {@code next()} on
* the ResultSet; it is only supposed to extract values of the current row.
*
Exactly what the implementation chooses to do is up to it:
* A trivial implementation might simply count rows, while another
* implementation might build an XML document.
* @param rs the ResultSet to process (pre-initialized for the current row)
* @throws SQLException if a SQLException is encountered getting
* column values (that is, there's no need to catch SQLException)
*/
void processRow(ResultSet rs) throws SQLException;
}