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1
19
20 package com.sslexplorer.jdbc;
21
22 import java.sql.Connection  ;
23 import java.sql.DriverManager ;
24 import java.sql.PreparedStatement ;
25 import java.sql.ResultSet ;
26 import java.sql.SQLException ;
27 import java.sql.Statement ;
28 import java.util.Hashtable ;
29 import java.util.Iterator ;
30 import java.util.Map ;
31 import java.util.Vector ;
32
33 import org.apache.commons.logging.Log;
34 import org.apache.commons.logging.LogFactory;
35
36 public class JDBCConnectionImpl {
37
38 final static Log log = LogFactory.getLog(JDBCConnectionImpl.class);
39
40 static long currentId = 0;
41
42 private String key;
44 private long id;
45 private Connection conn;
46 private Hashtable preparedStatements = new Hashtable ();
47
48 private JDBCConnectionImpl(String key, JDBCConnectionSettings settings) throws SQLException ,
50 ClassNotFoundException {
51 id = currentId++;
52 this.key = key;
53 Class.forName(settings.driver);
54 conn = DriverManager.getConnection(settings.url, settings.username, settings.password);
55 }
56
57 public void setAutoCommit(boolean autoCommit) throws SQLException {
58 conn.setAutoCommit(autoCommit);
59 }
60
61 String getKey() {
62 return key;
63 }
64
65 boolean isClosed() throws SQLException {
66 return conn.isClosed();
67 }
68
69 ResultSet executeQuery(String sqlString) throws SQLException {
70 Statement stmt = conn.createStatement();
71 ResultSet rs = stmt.executeQuery(sqlString);
72 return rs;
73 }
74
75 void execute(String sqlString) throws SQLException {
76 Statement stmt = conn.createStatement();
77 try {
78 stmt.execute(sqlString);
79 }
80 finally {
81 stmt.close();
82 }
83 }
84
85 synchronized PreparedStatement aquirePreparedStatement(String key, String sqlString) throws SQLException {
86 Vector avail = (Vector ) preparedStatements.get(key);
87 if (avail == null) {
88 avail = new Vector ();
89 preparedStatements.put(key, avail);
90 }
91
92 if (avail.size() > 0) {
93 return (PreparedStatement ) avail.remove(0);
94 } else
95 return conn.prepareStatement(sqlString);
96 }
97
98 synchronized void releasePreparedStatement(String key, PreparedStatement ps) throws SQLException {
99 ps.clearParameters();
100 Vector avail = (Vector ) preparedStatements.get(key);
101 avail.add(ps);
102 }
103
104 public long getId() {
105 return id;
106 }
107
108 public Connection getConnection() {
109 return conn;
110 }
111
112 public static class JDBCPool {
113 private Hashtable poolDictionary = new Hashtable ();
115 private Hashtable poolSettings = new Hashtable ();
117
118 private JDBCPool() {
120 }
122 private static JDBCPool _instance;
124 public static JDBCPool getInstance() {
126 if (_instance == null) {
127 synchronized (JDBCPool.class) {
128 if (_instance == null) {
129 _instance = new JDBCPool();
130 }
131 }
132 }
133 return _instance;
134 }
135
136 public synchronized void createImpl(String key, String driver, String url, String username, String password)
137 throws SQLException , ClassNotFoundException {
138
139 Vector pool = new Vector ();
140
141 JDBCConnectionSettings settings = new JDBCConnectionSettings();
142 settings.driver = driver;
143 settings.url = url;
144 settings.username = username;
145 settings.password = password;
146
147 poolDictionary.put(key, pool);
148 poolSettings.put(key, settings);
149
150 pool.addElement(new JDBCConnectionImpl(key, settings));
151
152 }
153
154 public Map getPools() {
155 return poolDictionary;
156 }
157
158 public synchronized void closeAll() {
159 for (Iterator i = poolDictionary.entrySet().iterator(); i.hasNext();) {
160 Map.Entry entry = (Map.Entry ) i.next();
161 if (log.isInfoEnabled())
162 log.info("Closing connections for " + entry.getKey());
163 Vector pool = (Vector ) entry.getValue();
164 for (Iterator j = pool.iterator(); j.hasNext();) {
165 JDBCConnectionImpl conx = (JDBCConnectionImpl) j.next();
166 try {
167 conx.conn.close();
168 } catch (SQLException sqle) {
169 log.warn("Failed to close pooled connection. ", sqle);
170 }
171 }
172 }
173 poolDictionary.clear();
174
175 }
176
177 public synchronized JDBCConnectionImpl acquireImpl(String key) throws SQLException , ClassNotFoundException {
179 if (log.isDebugEnabled())
180 log.debug("Aquiring connection for " + key);
181
182 Vector pool = (Vector ) poolDictionary.get(key);
184 if (pool != null) {
185 while (pool.size() > 0) {
186 if (log.isDebugEnabled())
187 log.debug(pool.size() + " connections in pool.");
188 JDBCConnectionImpl impl = null;
189 impl = (JDBCConnectionImpl) pool.elementAt(pool.size() - 1);
191 pool.removeElementAt(pool.size() - 1);
193
194 if (impl.isClosed()) {
197 if (log.isDebugEnabled())
198 log.debug("Connecting for " + key + " is closed, get the next one");
199 continue;
200 }
201
202 if (log.isDebugEnabled())
203 log.debug("Found connection " + impl.toString());
204
205 return impl;
206 }
207 }
208 if (log.isDebugEnabled())
209 log.debug("Pool is empty, getting ");
210
211 JDBCConnectionSettings settings = (JDBCConnectionSettings) poolSettings.get(key);
212 return new JDBCConnectionImpl(key, settings);
214 }
215
216 public synchronized void releaseImpl(JDBCConnectionImpl impl) {
218 String key = impl.getKey();
219 Vector pool = (Vector ) poolDictionary.get(key);
220 if (pool == null) {
221 pool = new Vector ();
222 poolDictionary.put(key, pool);
223 }
224
225 pool.addElement(impl);
226 }
227 }
228
229 static class JDBCConnectionSettings {
230 String url;
231 String driver;
232 String cls;
233 String username;
234 String password;
235 }
236
237 public void rollback() throws SQLException {
238 conn.rollback();
239 }
240
241 public void commit() throws SQLException {
242 conn.commit();
243 }
244 }
245 |
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