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1
18
19 package org.apache.jmeter.protocol.jdbc.util;
20
21 import java.sql.Connection  ;
22 import java.sql.DatabaseMetaData ;
23 import java.sql.DriverManager ;
24 import java.sql.SQLException ;
25 import java.util.Hashtable ;
26 import java.util.Map ;
27
28 import org.apache.jmeter.protocol.jdbc.sampler.JDBCSampler;
29 import org.apache.jmeter.testelement.property.JMeterProperty;
30 import org.apache.jorphan.logging.LoggingManager;
31 import org.apache.log.Logger;
32
33
34
38 public class JMeter19ConnectionPool implements ConnectionPool
39 {
40 private static Logger log = LoggingManager.getLoggerForClass();
41 private static final int ABSOLUTE_MAX_CONNECTIONS = 100;
42
43 public static final String CONNECTIONS =
44 JDBCSampler.JDBCSAMPLER_PROPERTY_PREFIX + "connections";
45 public static final String MAXUSE =
46 JDBCSampler.JDBCSAMPLER_PROPERTY_PREFIX + "maxuse";
47
48 private final ConnectionObject connectionArray[];
49 private final Hashtable rentedConnections = new Hashtable ();
50
51 private final DBKey key;
52 private int maxConnections;
53
54 public JMeter19ConnectionPool(DBKey key, Map properties)
55 throws ConnectionPoolException
56 {
57 this.key = key;
58
59 this.maxConnections =
60 ((JMeterProperty) properties.get(CONNECTIONS)).getIntValue();
61 int maxUsage =
62 ((JMeterProperty) properties.get(MAXUSE)).getIntValue();
63
64 validateMaxConnections();
65
66 connectionArray = new ConnectionObject[maxConnections];
67 try
68 {
69 for (int i = 0; i < maxConnections; i++)
70 {
71 connectionArray[i] = new ConnectionObject(key, maxUsage);
72 }
73 }
74 catch (SQLException e)
75 {
76 log.error("Error initializing JDBC connection pool", e);
77 throw new ConnectionPoolException(
78 "Error initializing JDBC connection pool: " + e);
79 }
80 }
81
82
83 private void validateMaxConnections()
84 {
85 try
87 {
88 DatabaseMetaData md =
89 DriverManager
90 .getConnection(
91 key.getUrl(),
92 key.getUsername(),
93 key.getPassword())
94 .getMetaData();
95
96 int dbMax = md.getMaxConnections();
97 if (dbMax > 0 && maxConnections > dbMax)
98 {
99 log.warn(
100 "Connection pool configured for "
101 + maxConnections
102 + " but database claims to allow only "
103 + dbMax
104 + ". Reducing the pool size, but problems may occur "
105 + "if multiple connection pools are in use for the "
106 + "same database.");
107 maxConnections = dbMax;
108 }
109 else if (maxConnections > ABSOLUTE_MAX_CONNECTIONS)
110 {
111 maxConnections = ABSOLUTE_MAX_CONNECTIONS;
112 }
113 }
114 catch (Exception e)
115 {
116 log.error("Couldn't get connection to database", e);
117 maxConnections = 0;
118 return;
119 }
120 finally
121 {
122 }
134 }
135
136
140 public Connection getConnection() throws ConnectionPoolException
141 {
142 if (connectionArray.length == 0)
143 {
144 throw new NoConnectionsAvailableException();
145 }
146
147 Connection c = null;
148 int attempts = 0;
149 while (attempts < 20 && (c = attemptGetConnection()) == null)
150 {
151 try
152 {
153 Thread.sleep(10);
154 }
155 catch (Exception err)
156 {
157 attempts++;
158 }
159 }
160
161 return c;
162 }
163
164 private Connection attemptGetConnection()
165 {
166 Connection c = null;
167 int index = (int) (100 * Math.random());
168 int count = -1;
169 while (++count < maxConnections && c == null)
170 {
171 index++;
172 c = connectionArray[index % maxConnections].grab();
173 }
174
175 if (c != null)
176 {
177 rentedConnections.put(c, connectionArray[index % maxConnections]);
178 }
179
180 return c;
181 }
182
186 public void returnConnection(Connection c)
187 {
188 if (c == null)
189 {
190 return;
191 }
192
193 ConnectionObject connOb = (ConnectionObject) rentedConnections.get(c);
194 if (connOb != null)
195 {
196 rentedConnections.remove(c);
197 connOb.release();
198 }
199 else
200 {
201 log.warn("DBConnectionManager: Lost a connection connection='" + c);
202 c = null;
203 }
204 }
205
206
209 public Connection newConnection(DBKey key) throws SQLException
210 {
211 return DriverManager.getConnection(
212 key.getUrl(),
213 key.getUsername(),
214 key.getPassword());
215 }
216
217
220 public void close()
221 {
222 for (int i = 0; i < connectionArray.length; i++)
223 {
224 connectionArray[i].close();
225 connectionArray[i] = null;
226 }
227 }
228 }
229 |
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