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Java > Open Source Codes > org > apache > cayenne > dba > mysql > MySQLSniffer


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19
20 package org.apache.cayenne.dba.mysql;
21
22 import java.sql.DatabaseMetaData JavaDoc;
23 import java.sql.ResultSet JavaDoc;
24 import java.sql.SQLException JavaDoc;
25 import java.sql.Statement JavaDoc;
26
27 import org.apache.cayenne.dba.DbAdapter;
28 import org.apache.cayenne.dba.DbAdapterFactory;
29
30 /**
31  * Detects MySQL database from JDBC metadata.
32  *
33  * @since 1.2
34  * @author Andrus Adamchik
35  */
36 public class MySQLSniffer implements DbAdapterFactory {
37
38     public DbAdapter createAdapter(DatabaseMetaData JavaDoc md) throws SQLException JavaDoc {
39         String JavaDoc dbName = md.getDatabaseProductName();
40         if (dbName == null || dbName.toUpperCase().indexOf("MYSQL") < 0) {
41             return null;
42         }
43
44         // if InnoDB is used as a default engine, allow PK
45 Statement JavaDoc statement = md.getConnection().createStatement();
46         boolean supportFK = false;
47
48         try {
49             ResultSet JavaDoc rs = statement.executeQuery("SHOW VARIABLES LIKE 'table_type'");
50             try {
51                 if (rs.next()) {
52                     String JavaDoc tableType = rs.getString(2);
53                     supportFK = tableType != null
54                             && tableType.toUpperCase().equals("INNODB");
55                 }
56             }
57             finally {
58                 rs.close();
59             }
60         }
61         finally {
62             statement.close();
63         }
64
65         MySQLAdapter adapter = new MySQLAdapter();
66         adapter.setSupportsFkConstraints(supportFK);
67         return adapter;
68     }
69 }
70
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