destroy servlet database connection

hello guys

i am facing a problem regarding one of my servlet

i use init() method to initialize the connection to the database and after that i use destroy method to disconnect from the database.
like this

destroy() {
try {

connection.close();
}
catch (Exception e){

out.println(e);
}

but the problem is after a couple of hours and i think when the destroy method executed any request to the database failed.
this is the exception

java.sql.SQLException: No operations allowed after connection closed.

now i dont really know the solution for this matter but if there is a way to solve it please dont hasitate to response

thanks

can any one help

the second thing is the method destroy() shutdown all my connection to the server or the database so in case i request data from the database in the future should the database response.

thanks alot

Most likely the database is closing the connection due to inactivity well before your container unloads your servlet and calls destroy. This would be a timeout setting on the database config files. You should perhaps make database connections on a per request basis if there really is hours between requests or look into connection pooling support for your servlet container.

thank you joe

now what is connection pooling ? and how can i get one?

until now i cant connect to the database

and i get this message

unavailable invoker

strange