001/* 002 * Copyright 2002-2012 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.ResultSet; 020import java.sql.SQLException; 021 022/** 023 * An interface used by {@link JdbcTemplate} for processing rows of a 024 * {@link java.sql.ResultSet} on a per-row basis. Implementations of 025 * this interface perform the actual work of processing each row 026 * but don't need to worry about exception handling. 027 * {@link java.sql.SQLException SQLExceptions} will be caught and handled 028 * by the calling JdbcTemplate. 029 * 030 * <p>In contrast to a {@link ResultSetExtractor}, a RowCallbackHandler 031 * object is typically stateful: It keeps the result state within the 032 * object, to be available for later inspection. See 033 * {@link RowCountCallbackHandler} for a usage example. 034 * 035 * <p>Consider using a {@link RowMapper} instead if you need to map 036 * exactly one result object per row, assembling them into a List. 037 * 038 * @author Rod Johnson 039 * @author Juergen Hoeller 040 * @see JdbcTemplate 041 * @see RowMapper 042 * @see ResultSetExtractor 043 * @see RowCountCallbackHandler 044 */ 045public interface RowCallbackHandler { 046 047 /** 048 * Implementations must implement this method to process each row of data 049 * in the ResultSet. This method should not call {@code next()} on 050 * the ResultSet; it is only supposed to extract values of the current row. 051 * <p>Exactly what the implementation chooses to do is up to it: 052 * A trivial implementation might simply count rows, while another 053 * implementation might build an XML document. 054 * @param rs the ResultSet to process (pre-initialized for the current row) 055 * @throws SQLException if a SQLException is encountered getting 056 * column values (that is, there's no need to catch SQLException) 057 */ 058 void processRow(ResultSet rs) throws SQLException; 059 060}