jdbc problem with multiple connections

From: Chris Thompson <chris(at)lightershade(dot)com>
To: <pgsql-jdbc(at)postgresql(dot)org>
Subject: jdbc problem with multiple connections
Date: 2002-10-06 12:27:02
Message-ID: Pine.LNX.4.33L2.0210061308280.30623-100000@boyce.ednet.co.uk
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Lists: pgsql-jdbc

Hi,
I am opening 3 different database connection all calling the same method, which returns a
Connection or throws an Exception.

The first 2 attempts connections work fine, the third fails with a
ClassNotFoundException for org.postgresq.Driver. They are all using the
same org.postgresql.Driver.

Has anyone any suggestions as to why this might happen?

Postgres is running, accepting tcp connections on all hosts and
configured appropriately, no firewalls are in the way.

Cheers for any help,
Chris

// DBMgr.java
import java.sql.*;
/**
* Example of problem code
* Opens 3 connections, the first 2 work, third fails?!
*
*/
public class DBMgr {

private String a_driver = "org.postgresql.Driver";
private String a_url = "jdbc:postgresql://server-a/a";
private String a_user = "a;
private String a_password = "a";

private String b_driver = "org.postgresql.Driver";
private String b_url = "jdbc:postgresql://server-b/b";
private String b_user = "b";
private String b_password = "b";

private String c_driver = "org.postgresq.Driver";
private String c_url = "jdbc:postgesql://server-c";
private String c_user = "c";
private String c_password = "c";

public DBMgr() {}

public Connection getAConn() throws ClassNotFoundException, SQLException {

return connectDB(a_driver, a_url, a_user, a_password);
}

public Connection getBConn() throws ClassNotFoundException, SQLException {

return connectDB(b_driver, b_url, b_user, b_password);
}

public Connection getCRMConn() throws ClassNotFoundException, SQLException {
return connectDB(c_driver, c_url, c_user, c_password);
}

public void closeConn(Connection conn) {
try {
conn.close();
} catch (SQLException e) {

System.out.println(e.getMessage());
}
}

/**
* Returns a connection to a database
* @param String db_driver
* @param String db_url
* @param String db_user
* @param String db_password
* @return Connection conn
*/
public Connection connectDB(String db_driver, String db_url, String db_user, String db_password) throws ClassNotFoundException, SQLException {

Connection connection;

// try to load the postgres driver
Class.forName(db_driver);

// Connect to the database
connection = DriverManager.getConnection(db_url, db_user, db_password);

System.out.println("Got connection to " + db_driver + ", " + db_url + ", " + db_user + ", ******");

return connection;
}

}

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