01: /*
02: * (c) Copyright 2007 by Volker Bergmann. All rights reserved.
03: *
04: * Redistribution and use in source and binary forms, with or without
05: * modification, is permitted under the terms of the
06: * GNU General Public License.
07: *
08: * For redistributing this software or a derivative work under a license other
09: * than the GPL-compatible Free Software License as defined by the Free
10: * Software Foundation or approved by OSI, you must first obtain a commercial
11: * license to this software product from Volker Bergmann.
12: *
13: * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
14: * WITHOUT A WARRANTY OF ANY KIND. ALL EXPRESS OR IMPLIED CONDITIONS,
15: * REPRESENTATIONS AND WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF
16: * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE
17: * HEREBY EXCLUDED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
18: * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
19: * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
20: * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
21: * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
22: * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
23: * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24: * POSSIBILITY OF SUCH DAMAGE.
25: */
26:
27: package org.databene.platform.db;
28:
29: import org.apache.commons.logging.Log;
30: import org.apache.commons.logging.LogFactory;
31: import org.databene.commons.StringUtil;
32:
33: import java.sql.Connection;
34: import java.sql.Statement;
35: import java.sql.SQLException;
36: import java.sql.ResultSet;
37: import java.util.Iterator;
38:
39: /**
40: * Creates Iterators for stepping through query results.<br/>
41: * <br/>
42: * Created: 17.08.2007 18:48:20
43: */
44: public class QueryIterable implements Iterable<ResultSet> {
45:
46: private static final Log sqlLogger = LogFactory
47: .getLog("org.databene.benerator.SQL");
48:
49: private Connection connection;
50: private String query;
51: private int fetchSize;
52:
53: public QueryIterable(Connection connection) {
54: this (connection, null, 100);
55: }
56:
57: public QueryIterable(Connection connection, String query) {
58: this (connection, query, 100);
59: }
60:
61: public QueryIterable(Connection connection, String query,
62: int fetchSize) {
63: this .connection = connection;
64: this .query = query;
65: this .fetchSize = fetchSize;
66: }
67:
68: public String getQuery() {
69: return query;
70: }
71:
72: public void setQuery(String query) {
73: this .query = query;
74: }
75:
76: public Iterator<ResultSet> iterator() {
77: if (connection == null)
78: throw new IllegalStateException("'connection' is null");
79: if (StringUtil.isEmpty(query))
80: throw new IllegalStateException("'query' is empty or null");
81: try {
82: if (sqlLogger.isDebugEnabled())
83: sqlLogger.debug(query);
84: Statement statement = connection.createStatement();
85: statement.setFetchSize(fetchSize);
86: ResultSet resultSet = statement.executeQuery(query);
87: return new ResultSetIterator(resultSet, query);
88: } catch (SQLException e) {
89: throw new RuntimeException("Error in query: " + query, e);
90: }
91: }
92:
93: @Override
94: public String toString() {
95: return getClass().getSimpleName() + '[' + query + ']';
96: }
97: }
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