1 /*
2 * Copyright 2002-2012 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package org.springframework.jdbc.core;
18
19 import java.sql.ResultSet;
20 import java.sql.SQLException;
21
22 /**
23 * An interface used by {@link JdbcTemplate} for processing rows of a
24 * {@link java.sql.ResultSet} on a per-row basis. Implementations of
25 * this interface perform the actual work of processing each row
26 * but don't need to worry about exception handling.
27 * {@link java.sql.SQLException SQLExceptions} will be caught and handled
28 * by the calling JdbcTemplate.
29 *
30 * <p>In contrast to a {@link ResultSetExtractor}, a RowCallbackHandler
31 * object is typically stateful: It keeps the result state within the
32 * object, to be available for later inspection. See
33 * {@link RowCountCallbackHandler} for a usage example.
34 *
35 * <p>Consider using a {@link RowMapper} instead if you need to map
36 * exactly one result object per row, assembling them into a List.
37 *
38 * @author Rod Johnson
39 * @author Juergen Hoeller
40 * @see JdbcTemplate
41 * @see RowMapper
42 * @see ResultSetExtractor
43 * @see RowCountCallbackHandler
44 */
45 public interface RowCallbackHandler {
46
47 /**
48 * Implementations must implement this method to process each row of data
49 * in the ResultSet. This method should not call {@code next()} on
50 * the ResultSet; it is only supposed to extract values of the current row.
51 * <p>Exactly what the implementation chooses to do is up to it:
52 * A trivial implementation might simply count rows, while another
53 * implementation might build an XML document.
54 * @param rs the ResultSet to process (pre-initialized for the current row)
55 * @throws SQLException if a SQLException is encountered getting
56 * column values (that is, there's no need to catch SQLException)
57 */
58 void processRow(ResultSet rs) throws SQLException;
59
60 }