Name: gm110360 Date: 09/12/2001


java version "1.3.1"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.1-b24)
Java HotSpot(TM) Client VM (build 1.3.1-b24, mixed mode)

We have found a serious memory leak using the Sun JDBC/ODBC bridge to access
values of type DATE. Running under a normal load on a small test server our
Web application will run out of memory in less than 12 hours.

///////////////////////////////////////////////////////////////////////////////
/** This class demonstrates a memory leak in the JDBC-ODBC bridge.
 **/

import java.sql.*;

///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
public final class Example
{
    ///////////////////////////////////////////////////////////////////////////
    private static final String JDBC_DRIVER =
        "sun.jdbc.odbc.JdbcOdbcDriver";
    // Example JDBC URL's - note that the site specific info has been stripped
    private static final String JDBC_URL =
        "jdbc:odbc:;driver=Oracle ODBC Driver;server=;dbq=;uid=;pwd=";
// "jdbc:odbc:;driver=Microsoft ODBC for Oracle;server=;uid=;pwd=";
// "jdbc:odbc:;driver=SQL Server;server=;database=;uid=;pwd=";
    private static final String JDBC_QUERY =
        "SELECT SYSDATE FROM DUAL";
// "SELECT GETDATE()";
    private static final long ITERATION_COUNT = 30000;
    
    ///////////////////////////////////////////////////////////////////////////
    public static void main(String[] arguments)
    {
        try {
            Class.forName(JDBC_DRIVER);
            Connection connection = DriverManager.getConnection(JDBC_URL);
            for (long i = 0; i < ITERATION_COUNT; ++i) {
                Statement statement = connection.createStatement();
                ResultSet resultSet = statement.executeQuery(JDBC_QUERY);
                int columnCount = resultSet.getMetaData().getColumnCount();
                while (resultSet.next()) {
                    for (int c = 1; c <= columnCount; ++c) {
                        Object value = resultSet.getObject(c);
                    }
                }
                resultSet.close();
                statement.close();
            }
            connection.close();
        } catch (Exception ex) {
            System.err.println("Exception: " + ex);
        }
    }

    ///////////////////////////////////////////////////////////////////////////
}

///////////////////////////////////////////////////////////////////////////////

We have demonstrated the leak on systems with the following configurations:

System 1:

OS: Windows NT version 4.00.1381
Java VM(s): HotSpot Client VM 1.3.1-b24
              HotSpot Client VM 1.3.0-C
              HotSpot Client VM 1.4.0-beta2-b77
ODBC: 3.510.4202.0
ODBC drivers: Microsoft ODBC for Oracle 2.573.4202.0
              Oracle ODBC Driver 8.01.06.00
              SQL Server 3.70.06.90
                              
System 2:
                                  
OS: Windows NT 4.00.1381
Java VM: HotSpot Client VM 1.3.1-b24
ODBC: 3.510.4202.0
ODBC drivers: Microsoft ODBC for Oracle 2.573.4202.0
              Oracle ODBC Driver 8.00.05.00
              SQL Server 3.70.06.90
                              
System 3:
                              
OS: Windows 2000 5.00.2195
Java VM: HotSpot Client VM 1.3.1-b24
ODBC: 3.520.5303.2
ODBC drivers: Microsoft ODBC for Oracle 2.573.5303.00
              Oracle ODBC Driver 8.00.05.00
              SQL Server 3.70.08.21
(Review ID: 131434)
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