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16 package org.outerj.daisy.jdbcutil;
17
18 import org.apache.avalon.framework.logger.Logger;
19
20 import javax.sql.DataSource  ;
21 import java.sql.Connection ;
22 import java.sql.Statement ;
23 import java.sql.SQLException ;
24 import java.util.Map ;
25 import java.util.HashMap ;
26 import java.lang.reflect.Constructor ;
27
28 public abstract class JdbcHelper {
29 private Logger logger;
30 private static Map jdbcHelpers = new HashMap ();
31
32 static {
33 jdbcHelpers.put("MySQL", MySqlJdbcHelper.class);
34 jdbcHelpers.put("PostgreSQL", PostgresqlJdbcHelper.class);
35 jdbcHelpers.put("Oracle", OracleJdbcHelper.class);
36 }
37
38 public static JdbcHelper getInstance(String databaseProductName, Logger logger) {
39 Class clazz = (Class ) jdbcHelpers.get(databaseProductName);
40 if (clazz == null) {
41 throw new RuntimeException ("Unsupported database: " + databaseProductName);
42 }
43
44 try {
45 Constructor constructor = clazz.getConstructor(new Class []{Logger.class});
46 return (JdbcHelper) constructor.newInstance(new Object []{logger});
47 } catch (Exception e) {
48 throw new RuntimeException ("Error creating JdbcHelper.", e);
49 }
50 }
51
52 public static JdbcHelper getInstance(DataSource dataSource, Logger logger) {
53 String databaseProductName = null;
54 try {
55 Connection conn = dataSource.getConnection();
56 try {
57 databaseProductName = conn.getMetaData().getDatabaseProductName();
58 } finally {
59 conn.close();
60 }
61 } catch (Exception e) {
62 throw new RuntimeException ("Problem determing database product name.", e);
63 }
64 return JdbcHelper.getInstance(databaseProductName, logger);
65 }
66
67
68 private JdbcHelper(Logger logger) {
69 this.logger = logger;
70 }
71
72 public void closeStatement(Statement stmt) {
73 if (stmt == null)
74 return;
75
76 try {
77 stmt.close();
79 } catch (Exception e) {
80 logger.error("Error closing SQL statement.", e);
81 }
82 }
83
84 public void closeConnection(Connection conn) {
85 if (conn == null)
86 return;
87
88 try {
89 if (!conn.getAutoCommit()) {
90 conn.commit(); conn.setAutoCommit(true);
92 }
93 } catch (Throwable e) {
94 logger.error("Error setting connection to autocommit + committing.", e);
95 }
96
97 try {
98 conn.close();
99 } catch (Throwable e) {
100 logger.error("Error closing connection.", e);
101 }
102 }
103
104 public void rollback(Connection conn) {
105 try {
106 if (conn != null)
107 conn.rollback();
108 } catch (Throwable e) {
109 logger.error("Error rolling back transaction.", e);
110 }
111 }
112
113 public abstract void startTransaction(Connection conn) throws SQLException ;
114
115 public abstract String getSharedLockClause();
116
117
118 public String [] getStringLengthFunction() {
119 return new String [] { "CHAR_LENGTH(", ")" };
120 }
121
122 public String [] getStringConcatFunction() {
123 return new String [] { "CONCAT(", ")" };
124 }
125
126 public String getStringLeftFunction() {
127 return "LEFT";
128 }
129
130 public String getStringRightFunction() {
131 return "RIGHT";
132 }
133
134 public String getSubstringFunction() {
135 return "SUBSTRING";
136 }
137
138 public String getLowerCaseFunction() {
139 return "LCASE";
140 }
141
142 public String getUpperCaseFunction() {
143 return "UCASE";
144 }
145
146 public String [] getExtractYearFunction() {
147 return new String [] { "EXTRACT(YEAR FROM ", ")"};
148 }
149
150
151 public String [] getExtractMonthFunction() {
152 return new String [] { "EXTRACT(MONTH FROM ", ")"};
153 }
154
155 public String [] getDayOfWeekFunction() {
156 return new String [] {"DAYOFWEEK(", ")"};
157 }
158
159 public String [] getDayOfMonthFunction() {
160 return new String [] {"DAYOFMONTH(", ")"};
161 }
162
163 public String [] getDayOfYearFunction() {
164 return new String [] {"DAYOFYEAR(", ")"};
165 }
166
167
168 public String [] getWeekFunction() {
169 return new String [] { "WEEK(", ")" };
170 }
171
172 static class MySqlJdbcHelper extends JdbcHelper {
173 public MySqlJdbcHelper(Logger logger) {
174 super(logger);
175 }
176
177 public void startTransaction(Connection conn) throws SQLException {
178 conn.setAutoCommit(false);
181 }
182
183 public String getSharedLockClause() {
184 return "lock in share mode";
185 }
186
187 public String [] getWeekFunction() {
188 return new String [] { "WEEK(", ", 2)" };
189 }
190 }
191
192 static class PostgresqlJdbcHelper extends JdbcHelper {
193 public PostgresqlJdbcHelper(Logger logger) {
194 super(logger);
195 }
196
197 public void startTransaction(Connection conn) throws SQLException {
198 conn.setTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE);
199 conn.setAutoCommit(false);
200 }
201
202 public String getSharedLockClause() {
203 return "for update";
204 }
205 }
206
207 static class OracleJdbcHelper extends JdbcHelper {
208 public OracleJdbcHelper(Logger logger) {
209 super(logger);
210 }
211
212 public void startTransaction(Connection conn) throws SQLException {
213 conn.setTransactionIsolation(Connection.TRANSACTION_READ_COMMITTED);
214 conn.setAutoCommit(false);
215 }
216
217 public String getSharedLockClause() {
218 return "for update";
219 }
220 }
221 }
222 |
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