Re: Tomcat 4.x and Database Connection Pooling
I don't understand why you need it to be abstract.
I don't think that Struts necessarily changes it either.
Remember that your servlets calling the class are multi-threaded. That's the
one thing that I completely misunderstood when I first started writing
servlets.
As I understand it, just say 3 simultaneous requests come in for the servlet
that uses your DatabaseManager class. The servlet will create 3 threads to
deal with these requests. Each thread will create an instance of your
DatabaseManager class (unless you make it a static class variable which
would probably be a bad idea). Each instance of the DatabaseManager class
(one instance for each servlet thread) will then grab a database connection
from the database pool manager using JNDI. Therefore, do not employ global
static variables or else you'll need to use synchronized and that will also
defeat the object of database pooling.
Please correct me if I'm wrong and sorry if I have not answered your
question. Be aware that I'm not a java maestro.
Soefara
From: Ric Searle [EMAIL PROTECTED]
Reply-To: Tomcat Users List [EMAIL PROTECTED]
To: Tomcat Users List [EMAIL PROTECTED]
Subject: Re: Tomcat 4.x and Database Connection Pooling
Date: Thu, 11 Apr 2002 20:17:32 +0100
Thanks to everyone who's commented on this - I can't believe that I
hadn't come across the JNDI solution, but it's working beautifully now.
So onto the next, closely related issue...
I'm accessing my database, via JNDI, using a class called
DatabaseManager. My aim is that this class abstracts the database
backend, so I can just call addUser(myUser), and it will take care of
the SQL stuff behind the scenes. At the moment, this DatabaseManager
contains code similar to Soefara's below to get a connection for itself
whenever it has to make a db request.
My confusion is what to do with this class - Should I declare it as
abstract? Does that ruin some of the pooling stuff? I would really
like to be able to create a global instance of this class, instantiated
when the server starts, since individual requests don't need their own
DatabaseManager. But I'm using Struts, and I don't know how to do
that! Arghh...
Any thoughts/experiences?
Ric Searle
Web Application Developer
--
Dialogue Communications Ltd
http://www.dialogue.co.uk
+44 (0) 114 221 0307
On Thursday, April 11, 2002, at 06:02 pm, Craig R. McClanahan wrote:
On Thu, 11 Apr 2002, Soefara Redzuan wrote:
Date: Thu, 11 Apr 2002 10:46:14 +0800
From: Soefara Redzuan [EMAIL PROTECTED]
Reply-To: Tomcat Users List [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: Re: Tomcat 4.x and Database Connection Pooling
Tomcat: As far as I'm concerned, JNDI support is a now and forever
more
feature of Tomcat 4 and later. It's the standard access mechanism
for J2EE
app servers as well.
This is what I love to hear. With so many changes (servlets to JSP to
Struts) over the last few years, future-proofing is so important.
Recommendation: If you can, you should use JNDI based access to data
sources. This is both portable across containers, and portable across
Struts versus non-Struts applications.
In addition, it can be used from
directly from within a JavaBean implementing your business logic,
without requiring a reference to ActionServlet or the servlet context
(or
the web layer at all).
Really ? This is incredibly important news to me. I've been acquiring
the
JNDI resource within my servlet then passing it as a parameter to my
Javabean which is a terrible mechanism because it makes my javabean
dependent on the servlet :(
So, are we saying that once we've set up a pooled database connection
JNDI
resource in server.xml and web.xml, any Javabean that is called by a
serlvet
or JSP can make use of this JNDI resource directly like this
In the javabean.
import javax.naming.NamingException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingEnumeration;
import javax.naming.directory.InitialDirContext;
class mybean() {
java.sql.Connection conn
get getPooledDatabaseConnection() {
Context ctx = new InitialContext();
Context envCtx = (Context) ctx.lookup(java:/comp/env/);
DataSource ds = (DataSource) envCtx.lookup(jdbc/dbpool);
conn = ds.getConnection();
}
...
}
If so, this is going to make development much easier. :-)
Yep ... that is exactly the pattern you can use. Nice, isn't it?
Soefara.
Craig
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For additional
Re: Tomcat 4.x and Database Connection Pooling
On Thu, 11 Apr 2002, Soefara Redzuan wrote:
Date: Thu, 11 Apr 2002 10:46:14 +0800
From: Soefara Redzuan [EMAIL PROTECTED]
Reply-To: Tomcat Users List [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: Re: Tomcat 4.x and Database Connection Pooling
Tomcat: As far as I'm concerned, JNDI support is a now and forever more
feature of Tomcat 4 and later. It's the standard access mechanism for J2EE
app servers as well.
This is what I love to hear. With so many changes (servlets to JSP to
Struts) over the last few years, future-proofing is so important.
Recommendation: If you can, you should use JNDI based access to data
sources. This is both portable across containers, and portable across
Struts versus non-Struts applications.
In addition, it can be used from
directly from within a JavaBean implementing your business logic,
without requiring a reference to ActionServlet or the servlet context (or
the web layer at all).
Really ? This is incredibly important news to me. I've been acquiring the
JNDI resource within my servlet then passing it as a parameter to my
Javabean which is a terrible mechanism because it makes my javabean
dependent on the servlet :(
So, are we saying that once we've set up a pooled database connection JNDI
resource in server.xml and web.xml, any Javabean that is called by a serlvet
or JSP can make use of this JNDI resource directly like this
In the javabean.
import javax.naming.NamingException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingEnumeration;
import javax.naming.directory.InitialDirContext;
class mybean() {
java.sql.Connection conn
get getPooledDatabaseConnection() {
Context ctx = new InitialContext();
Context envCtx = (Context) ctx.lookup(java:/comp/env/);
DataSource ds = (DataSource) envCtx.lookup(jdbc/dbpool);
conn = ds.getConnection();
}
...
}
If so, this is going to make development much easier. :-)
Yep ... that is exactly the pattern you can use. Nice, isn't it?
Soefara.
Craig
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Re: Tomcat 4.x and Database Connection Pooling
Thanks to everyone who's commented on this - I can't believe that I
hadn't come across the JNDI solution, but it's working beautifully now.
So onto the next, closely related issue...
I'm accessing my database, via JNDI, using a class called
DatabaseManager. My aim is that this class abstracts the database
backend, so I can just call addUser(myUser), and it will take care of
the SQL stuff behind the scenes. At the moment, this DatabaseManager
contains code similar to Soefara's below to get a connection for itself
whenever it has to make a db request.
My confusion is what to do with this class - Should I declare it as
abstract? Does that ruin some of the pooling stuff? I would really
like to be able to create a global instance of this class, instantiated
when the server starts, since individual requests don't need their own
DatabaseManager. But I'm using Struts, and I don't know how to do
that! Arghh...
Any thoughts/experiences?
Ric Searle
Web Application Developer
--
Dialogue Communications Ltd
http://www.dialogue.co.uk
+44 (0) 114 221 0307
On Thursday, April 11, 2002, at 06:02 pm, Craig R. McClanahan wrote:
On Thu, 11 Apr 2002, Soefara Redzuan wrote:
Date: Thu, 11 Apr 2002 10:46:14 +0800
From: Soefara Redzuan [EMAIL PROTECTED]
Reply-To: Tomcat Users List [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: Re: Tomcat 4.x and Database Connection Pooling
Tomcat: As far as I'm concerned, JNDI support is a now and forever
more
feature of Tomcat 4 and later. It's the standard access mechanism
for J2EE
app servers as well.
This is what I love to hear. With so many changes (servlets to JSP to
Struts) over the last few years, future-proofing is so important.
Recommendation: If you can, you should use JNDI based access to data
sources. This is both portable across containers, and portable across
Struts versus non-Struts applications.
In addition, it can be used from
directly from within a JavaBean implementing your business logic,
without requiring a reference to ActionServlet or the servlet context
(or
the web layer at all).
Really ? This is incredibly important news to me. I've been acquiring
the
JNDI resource within my servlet then passing it as a parameter to my
Javabean which is a terrible mechanism because it makes my javabean
dependent on the servlet :(
So, are we saying that once we've set up a pooled database connection
JNDI
resource in server.xml and web.xml, any Javabean that is called by a
serlvet
or JSP can make use of this JNDI resource directly like this
In the javabean.
import javax.naming.NamingException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingEnumeration;
import javax.naming.directory.InitialDirContext;
class mybean() {
java.sql.Connection conn
get getPooledDatabaseConnection() {
Context ctx = new InitialContext();
Context envCtx = (Context) ctx.lookup(java:/comp/env/);
DataSource ds = (DataSource) envCtx.lookup(jdbc/dbpool);
conn = ds.getConnection();
}
...
}
If so, this is going to make development much easier. :-)
Yep ... that is exactly the pattern you can use. Nice, isn't it?
Soefara.
Craig
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Re: Tomcat 4.x and Database Connection Pooling
In the javabean.
import javax.naming.NamingException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingEnumeration;
import javax.naming.directory.InitialDirContext;
class mybean() {
java.sql.Connection conn
get getPooledDatabaseConnection() {
Context ctx = new InitialContext();
Context envCtx = (Context) ctx.lookup(java:/comp/env/);
DataSource ds = (DataSource) envCtx.lookup(jdbc/dbpool);
conn = ds.getConnection();
}
...
}
If so, this is going to make development much easier. :-)
Yep ... that is exactly the pattern you can use. Nice, isn't it?
It's so good we're updating all of our code to use this.
Now the whole MVC framework finally makes sense :-)
At least in a webapp, that is. I'm not sure how a standalone application
would be able to provide the JNDI environment to the same Javabeans but I'll
check the Sun JNDI mailing list.
Thank you for all the great work on Tomcat,
Soefara.
_
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Tomcat 4.x and Database Connection Pooling
Hi, I'm developing a web application using the Struts framework, running on Tomcat 4.0.3, from which I need to access a MySQL database. I've read various mailing lists etc looking for the best way to achieve this, but not had much luck. Struts provides a basic Connection Pool, but user comments suggest that this is not suitable for large-scale, high-traffic applications, and also that it will soon be removed from Struts in favour of a container-managed connection pool. I've found references to DbConnectionBroker and Jakarta's commons-dbcp module. It seems to make sense to use the latter, to keep the entire project neatly under the Jakarta project, but I'd appreciate comments on either. I'm fairly new to Tomcat (and Servlets), and I can't find any simple examples of how to use one of these connection pools. I suspect that I need to add something to my server.xml, and instantiate the pool in the servlet's init() method. It would be greatly appreciated if someone could provide some simple instructions to get me started - sample code would be fantastic. I hope to write about my experiences with this once I understand it - there seems to be a need for documentation in this area. Regards, Ric Searle Web Application Developer -- Dialogue Communications Ltd http://www.dialogue.co.uk +44 (0) 114 221 0307 -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
if performance is a critical requirement, than I would suggest writing a custom bean specific to the jdbc driver you intend to use. If Jakarta common provides all the features you need, than go with it. If your application needs to support multiple databases and jdbc drivers, be warned that not all jdbc drivers implement pooling, nor do they implement it the same way. In particular, jdbc drivers for SQLserver vary significantly in implementation, so doing real world benchmarks of each driver is critical. If commons doesn't provide the features you need, like scrollable resultsets, you may want to implement jdbc 2.0 compliant pooling driver using javax.sql api. good luck peter lin Ric Searle wrote: Hi, I'm developing a web application using the Struts framework, running on Tomcat 4.0.3, from which I need to access a MySQL database. I've read various mailing lists etc looking for the best way to achieve this, but not had much luck. Struts provides a basic Connection Pool, but user comments suggest that this is not suitable for large-scale, high-traffic applications, and also that it will soon be removed from Struts in favour of a container-managed connection pool. I've found references to DbConnectionBroker and Jakarta's commons-dbcp module. It seems to make sense to use the latter, to keep the entire project neatly under the Jakarta project, but I'd appreciate comments on either. I'm fairly new to Tomcat (and Servlets), and I can't find any simple examples of how to use one of these connection pools. I suspect that I need to add something to my server.xml, and instantiate the pool in the servlet's init() method. It would be greatly appreciated if someone could provide some simple instructions to get me started - sample code would be fantastic. I hope to write about my experiences with this once I understand it - there seems to be a need for documentation in this area. Regards, Ric Searle Web Application Developer -- Dialogue Communications Ltd http://www.dialogue.co.uk +44 (0) 114 221 0307 -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED] -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
Performance isn't so important as future-proofing - I don't want to have to re-write the db interface when struts drops it's connection pool provision, for example. I believe that mm.mysql does support pooling, although I take your point that others may not. I can't see us moving away from MySQL at the moment, so that's fine. My use of the database is really quite simple, so I'm sure that commons would be fine, but at the moment I don't know where to start integrating it with my Struts project. Does the container manage the pool (i.e. some server.xml configuration needed)? Or do I instantiate and manage the pool from within my application, and if so, how? Regards, Ric Searle Web Application Developer -- Dialogue Communications Ltd http://www.dialogue.co.uk +44 (0) 114 221 0307 On Wednesday, April 10, 2002, at 02:44 pm, peter lin wrote: if performance is a critical requirement, than I would suggest writing a custom bean specific to the jdbc driver you intend to use. If Jakarta common provides all the features you need, than go with it. If your application needs to support multiple databases and jdbc drivers, be warned that not all jdbc drivers implement pooling, nor do they implement it the same way. In particular, jdbc drivers for SQLserver vary significantly in implementation, so doing real world benchmarks of each driver is critical. If commons doesn't provide the features you need, like scrollable resultsets, you may want to implement jdbc 2.0 compliant pooling driver using javax.sql api. good luck peter lin -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
Hi Ric, Struts provides a basic Connection Pool, but user comments suggest that this is not suitable for large-scale, high-traffic applications, and also that it will soon be removed from Struts in favour of a container-managed connection pool So what will Tomcat Users do? Will Tomcat get a container manages connection pool? What is the reason for removing it form Struts? R. -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
Not sure - probably a little out of my depth here, but poolman (www.codestudio.com), which used to do connection pooling stuff is no longer available, and it's author claims that: If you are looking for connection and object pooling mechanisms, they can now be found in application servers such as JRun, Tomcat and the Jakarta Project, and other J2EE products and servers. Which is where my journey started...! Ric Searle Web Application Developer -- Dialogue Communications Ltd http://www.dialogue.co.uk +44 (0) 114 221 0307 On Wednesday, April 10, 2002, at 04:18 pm, rainer jünger wrote: Hi Ric, Struts provides a basic Connection Pool, but user comments suggest that this is not suitable for large-scale, high-traffic applications, and also that it will soon be removed from Struts in favour of a container-managed connection pool So what will Tomcat Users do? Will Tomcat get a container manages connection pool? What is the reason for removing it form Struts? R. -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
On Wed, 10 Apr 2002, rainer jünger wrote: Date: Wed, 10 Apr 2002 17:18:34 +0200 From: rainer jünger [EMAIL PROTECTED] Reply-To: Tomcat Users List [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Subject: Re: Tomcat 4.x and Database Connection Pooling Hi Ric, Struts provides a basic Connection Pool, but user comments suggest that this is not suitable for large-scale, high-traffic applications, and also that it will soon be removed from Struts in favour of a container-managed connection pool So what will Tomcat Users do? Will Tomcat get a container manages connection pool? http://jakarta.apache.org/tomcat/tomcat-4.0-doc/jndi-resources-howto.html What is the reason for removing it form Struts? That was a hypothetical example of a possible future situation that would cause the need to change your code. R. Craig McClanahan -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
RE: Tomcat 4.x and Database Connection Pooling
If you are looking for connection pooling which will work with any database check out DbConnectionBroker at http://www.javaexchange.com/ Jim -Original Message- From: Ric Searle [mailto:[EMAIL PROTECTED]] Sent: Wednesday, April 10, 2002 10:23 AM To: Tomcat Users List Subject: Re: Tomcat 4.x and Database Connection Pooling Not sure - probably a little out of my depth here, but poolman (www.codestudio.com), which used to do connection pooling stuff is no longer available, and it's author claims that: If you are looking for connection and object pooling mechanisms, they can now be found in application servers such as JRun, Tomcat and the Jakarta Project, and other J2EE products and servers. Which is where my journey started...! Ric Searle Web Application Developer -- Dialogue Communications Ltd http://www.dialogue.co.uk +44 (0) 114 221 0307 On Wednesday, April 10, 2002, at 04:18 pm, rainer jünger wrote: Hi Ric, Struts provides a basic Connection Pool, but user comments suggest that this is not suitable for large-scale, high-traffic applications, and also that it will soon be removed from Struts in favour of a container-managed connection pool So what will Tomcat Users do? Will Tomcat get a container manages connection pool? What is the reason for removing it form Struts? R. -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED] -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
Hi Craig, So what will Tomcat Users do? Will Tomcat get a container manages connection pool? http://jakarta.apache.org/tomcat/tomcat-4.0-doc/jndi-resources-howto.html What is the reason for removing it form Struts? That was a hypothetical example of a possible future situation that would cause the need to change your code. Sorry somehow I don't understand your answer. Did you wont to give me a hint that I can avoid to change the code in future by using JNDI? Still, what will happen to the Connection Pooling in future in Struts or in Tomcat? thanks, rainer juenger -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
Hi Jim, If you are looking for connection pooling which will work with any database check out DbConnectionBroker at http://www.javaexchange.com/ DbConnectionBroker is only providing as the developer calls it a 2 Tier model. So there is not actually a Connection Pool that manages the connection independently and the application is only taking and giving back connections. rainer juenger -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
On Wed, 10 Apr 2002, rainer jünger wrote: Date: Wed, 10 Apr 2002 18:42:39 +0200 From: rainer jünger [EMAIL PROTECTED] Reply-To: Tomcat Users List [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Subject: Re: Tomcat 4.x and Database Connection Pooling Hi Craig, So what will Tomcat Users do? Will Tomcat get a container manages connection pool? http://jakarta.apache.org/tomcat/tomcat-4.0-doc/jndi-resources-howto.html What is the reason for removing it form Struts? That was a hypothetical example of a possible future situation that would cause the need to change your code. Sorry somehow I don't understand your answer. Struts is ***NOT*** going to remove its own connection pool :-). However, the internal implementation is changing in Struts 1.1 to use the commons-dbcp implementation underneath. The person who made this comment was illustrating a *possible* scenario: - You write your app against the Struts APIs - Struts removed its connection pool - You now have to rewrite your apps Although this particular scenario won't happen, it does illustrate the potential for problems of reliance on specific APIs versus standardized approaches (when they exist). Did you wont to give me a hint that I can avoid to change the code in future by using JNDI? Struts developers who are writing apps for J2EE app servers, or servlet containers that support JNDI, should definitely use JNDI based data sources. This is the standard, portable, API for accessing resources. Still, what will happen to the Connection Pooling in future in Struts or in Tomcat? Struts: The connection pool API (org.apache.struts.util.GenericDataSource), the corresponding configuration in struts-config.xml, and the way to retrieve data sources from ActionServlet, will remain in Struts -- backwards compatibility is a key Struts feature. The internal implementation will change, but the APIs will not. Tomcat: As far as I'm concerned, JNDI support is a now and forever more feature of Tomcat 4 and later. It's the standard access mechanism for J2EE app servers as well. Recommendation: If you can, you should use JNDI based access to data sources. This is both portable across containers, and portable across Struts versus non-Struts applications. In addition, it can be used from directly from within a JavaBean implementing your business logic, without requiring a reference to ActionServlet or the servlet context (or the web layer at all). thanks, rainer juenger Craig -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
Hi Craig, Sorry somehow I don't understand your answer. Struts is ***NOT*** going to remove its own connection pool :-). Thanks thats an answer even I can understand ; ). However, the internal implementation is changing in Struts 1.1 to use the commons-dbcp implementation underneath. this might answer the primar question form Ric as well. Recommendation: If you can, you should use JNDI thanks I 'll consider it! Craig Your answer helped me now a lot. Rainer -- To unsubscribe: mailto:[EMAIL PROTECTED] For additional commands: mailto:[EMAIL PROTECTED] Troubles with the list: mailto:[EMAIL PROTECTED]
Re: Tomcat 4.x and Database Connection Pooling
Tomcat: As far as I'm concerned, JNDI support is a now and forever more
feature of Tomcat 4 and later. It's the standard access mechanism for J2EE
app servers as well.
This is what I love to hear. With so many changes (servlets to JSP to
Struts) over the last few years, future-proofing is so important.
Recommendation: If you can, you should use JNDI based access to data
sources. This is both portable across containers, and portable across
Struts versus non-Struts applications.
In addition, it can be used from
directly from within a JavaBean implementing your business logic,
without requiring a reference to ActionServlet or the servlet context (or
the web layer at all).
Really ? This is incredibly important news to me. I've been acquiring the
JNDI resource within my servlet then passing it as a parameter to my
Javabean which is a terrible mechanism because it makes my javabean
dependent on the servlet :(
So, are we saying that once we've set up a pooled database connection JNDI
resource in server.xml and web.xml, any Javabean that is called by a serlvet
or JSP can make use of this JNDI resource directly like this
In the javabean.
import javax.naming.NamingException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingEnumeration;
import javax.naming.directory.InitialDirContext;
class mybean() {
java.sql.Connection conn
get getPooledDatabaseConnection() {
Context ctx = new InitialContext();
Context envCtx = (Context) ctx.lookup(java:/comp/env/);
DataSource ds = (DataSource) envCtx.lookup(jdbc/dbpool);
conn = ds.getConnection();
}
...
}
If so, this is going to make development much easier. :-)
Soefara.
_
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Re: Tomcat 4.x and Database Connection Pooling
Performance isn't so important as future-proofing - I don't want to have to re-write the db interface when struts drops it's connection pool provision, for example. I believe that mm.mysql does support pooling, although I take your point that others may not. I can't see us moving away from MySQL at the moment, so that's fine. My use of the database is really quite simple, so I'm sure that commons would be fine, but at the moment I don't know where to start integrating it with my Struts project. Does the container manage the pool (i.e. some server.xml configuration needed)? Or do I instantiate and manage the pool from within my application, and if so, how? I believe the correct approach is to let container handle setting up the pool. Look at JNDI-Resources HOWTO in Tomcat's docs. Nix.
Re: Tomcat 4.x and Database Connection Pooling
Struts provides a basic Connection Pool, but user comments suggest that this is not suitable for large-scale, high-traffic applications, and also that it will soon be removed from Struts in favour of a container-managed connection pool So what will Tomcat Users do? Will Tomcat get a container manages connection pool? What is the reason for removing it form Struts? Struts, as I see it, is just an application framework. Connection pooling is a job for the JEE container, be it Tomcat or JBoss (or any other commercial). Nix.
