How to achieve Connection polling in JDBC

In my app code i am, for each and every method i am taking a Jdbc Connection( defined as a singleton class) using it and at the end of every method i am closing it.
Overall there is lots og conection opening and closing in that file. How can i get rid ofthis frequent opening and closing of connection.

Don't reinvent the wheel. Most application servers provide a mechanism for creating and managing connection pools. In such a scenario, you then request a connection from the data store and it will give you one if its open. Check the documentation for whatever application server you are using to see how to establish connection pools.

Scott,

Could you please tell me if the application is POJO (simple java class). We can't use application server datasource. In this case how to make use of Connection and data source.

As of my knowledge we can achieve this by Apache commons rite
by using
1. commons-dbcp.jar
2. commons-pooljar
3. commons-collections.jar

Is their any other alternative for connection pool and datasource usage in standalone Java application.