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From Dirk Verbeeck <dirk.verbe...@pandora.be>
Subject Re: help on DBCP
Date Tue, 12 Apr 2005 06:09:04 GMT
Having more then one connection open at a time is possible of course, 
the default configuration values allow 8 active connections.

In your example, how do you create/initialize the connectionPool variable?

-- Dirk

Arjen van der Weijden wrote:

> Hi,
> 
> Only if I close the connection after each SELECT the program runs fine, but
> the thing is: I want to have more than one connection open at a time. Do
> you know what could be the case?
> 
> 
> gr.
> 
> Arjen
> 
> 
> 
> 
>                                                                                     
                                                  
>                       Arjen van der                                                 
                                                  
>                       Weijden                     To:       "Jakarta Commons Users List"
<commons-user@jakarta.apache.org>             
>                       <Arjen.van.der.Weijd        cc:                            
                                                     
>                       en@rivm.nl>                 Subject:  Re: help on DBCP     
                                                     
>                                                                                     
                                                  
>                       04/11/2005 11:00 AM                                           
                                                  
>                       Please respond to                                             
                                                  
>                       "Jakarta Commons                                              
                                                  
>                       Users List"                                                   
                                                  
>                                                                                     
                                                  
>                                                                                     
                                                  
> 
> 
> 
> 
> Thanks Anshul,
> 
> Just returned from the weekend. I just replied to Dirk V. My problem seems
> to be somewhat transcendental.
> 
> Arjen
> 
> 
> 
> 
>                       "anshul khare"
> 
>                       <anshul.khare@tav        To:       "Jakarta Commons
> Users List" <commons-user@jakarta.apache.org>
>                       ant.com>                 cc:
> 
>                                                Subject:  Re: help on DBCP
> 
>                       04/08/2005 08:45
> 
>                       PM
> 
>                       Please respond to
> 
>                       "Jakarta Commons
> 
>                       Users List"
> 
> 
> 
> 
> 
> 
> 
> Hey,
> 
> I guess the problem lies with the order in which you close the ResultSet,
> Statement and Connection.
> 
> The "Statement"should be closed before the "ResultSet" followed  by
> "Connection". I had a similar problem and this fix worked for me.
> 
> Anshul
> 
> ----- Original Message -----
> From: "Arjen van der Weijden" <Arjen.van.der.Weijden@rivm.nl>
> To: <commons-user@jakarta.apache.org>
> Sent: Friday, April 08, 2005 7:08 AM
> Subject: help on DBCP
> 
> 
> 
>>Hi folks,
>>
>>Just started out examining DBCP, so I'm completely new to the subject.
>>I adapted the example given by Dirk V. (given below). I put some stuff in
> 
> a
> 
>>for loop.
>>
>>The PROBLEM is that after a few loops the program seems to hang (less
> 
> than
> 
>>10 connections).
>>
>>Can anybody help me on this, it must be someting trivial I guess?
>>
>>Configuration standard mysql installation on a redhat
>>
> 
> ____________________________________________________________________________
> 
> 
> _________________
> 
>>public class DataSourceExample {
>>
>>    public static void main(String[] args) {
>>      try {
>>            Class.forName("com.mysql.jdbc.Driver").newInstance();
>>        }
>>      catch (Exception ex) {
>>            ex.printStackTrace();
>>        }
>>
>>        DataSource dataSource =
>>
> 
> setupDataSource("jdbc:mysql://localhost/mysql?user=mysql&password=pizza");
> 
>>        Connection conn = null;
>>        Statement stmt = null;
>>        ResultSet rset = null;
>>
>>        for (int ii = 0; ii < 3; ii++) {
>>        try {
>>            for (int j = 0; j < 3; j++) {
>>            conn = dataSource.getConnection();
>>            stmt = conn.createStatement();
>>            String $query = "SELECT * FROM user";
>>            rset = stmt.executeQuery($query);
>>            System.out.println("Results:");
>>            int numcols = rset.getMetaData().getColumnCount();
>>            while(rset.next()) {
>>                for(int i=1;i<=numcols;i++) {
>>                    System.out.print("\t" + rset.getString(i));
>>                }
>>                System.out.println("");
>>            }
>>            }
>>        } catch(SQLException e) {
>>            e.printStackTrace();
>>        } finally {
>>            try { rset.close(); } catch(Exception e) { }
>>            try { stmt.close(); } catch(Exception e) { }
>>            try { conn.close(); } catch(Exception e) { }
>>        }
>>        }
>>    }
>>
>>    public static DataSource setupDataSource(String connectURI) {
>>            ConnectionFactory connectionFactory = new
>>DriverManagerConnectionFactory(connectURI,null);
>>            PoolableConnectionFactory poolableConnectionFactory = new \
>>
>>
> 
> PoolableConnectionFactory(connectionFactory,connectionPool,null,null,false,t
> 
> 
> rue);
> 
>>            PoolingDataSource dataSource = new
>>PoolingDataSource(connectionPool);
>>            return dataSource;
>>    }
>>}
>>
> 
> ____________________________________________________________________________
> 
> 
> 
>> DISCLAIMER:  http://www.rivm.nl/disclaimer
>>
>>
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