Re: R: JDBC Servlet Problems

> I wrote several servlets that access a MySQL database using a single,
> persistent, sychronized connection.

>    public static synchronized MySQLConnection getInstance(){
>       return theConnection;
>    }

There's no use for synchronized keyword in that method. The method is
synchronized, NOT the returned connection.

If you want to use a synchronized connection, you should do something
like (maybe you do it already):

MySQLConnection mConn = MySQLConnection.getInstance();
synchronized ( mConn ) {
  ...
}


I've seen somewhere simple conn-pools that are used like this:

List connList = new Vector(); //List holding the connections

doXXX, service etc...:
1. remove the last element (connection) from the list.
  1.1 if list was empty, create new connection.
2. use database with that connection.
3. put the connection back to list.

//1. :
conn = null;
synchronized ( connList ) {
 if ( connList.isEmpty() ) {
   //1.1
   conn = ...
 }
 else {
   conn = (Connection) connList.remove( connList.size() - 1 );
 }
}

//2. :
//Do the DB

//3. :
connList.add( conn );


1.1 should also contain some sort of maxConnection -limitation.

I hope this gave you some idea...

-clapu

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