Connection Pooling Creating a Connection object is one of the most expensive operations ConnectionPooling optimizes the time required to establish a connection with a database. Use the Connection objects more efficiently by creating a pool of connections Request for a Connection ObjectPool of Connection ObjectsDatabase ClientconnectionServlet, JSP, etc Connection Object returned to the Pool Initially consumes time but never spend time for establishing new connections.

Creating a Connection object is one of the most expensive operations

Use the Connection objects more efficiently by creating a pool of connections

Initially consumes time but never spend time for establishing new connections.

Connection PoolingConnection PoolingInternal Clients ( e.g., Servlets) Lookup DataSource Lookup DataSourceConnectionPoolDatabaseExternal ClientsConnection Type 2,3,or 4 JDBC DriverDataSourceConnectionConnectionDataSourceConnectionJNDI Tree

Connection Pooling Using the interfaces in the javax.sql package Contextcontext = newInitialContext(); DataSourceds = (DataSource)context.lookup("jdbc/wingsDB"); Connection con = ds.getConnection(username, password); Connection object that will automatically participate in the connection pooling

Using the interfaces in the javax.sql package

Connection object that will automatically participate in the connection pooling

Connection Pooling Classic way to achieve connection poolingRequest for a ConnectionPool of Connection ObjectsConnectionReturned Still-Open ConnectionWhich doesn’t support Connection PoolingCustom ConnectionCustom ConnectionCustom ConnectionCustom DataSourceCustom ConnectionVendor’s DataSourceVendor’s ConnectionVendor’s ConnectionVendor’s ConnectionVendor’s Connection

Classic way to achieve connection pooling

Connection PoolingMost JDBC vendors already have connection pooling facilities Connection pooling Utilities Jakarta Commons DBCPhttp://jakarta.apache.org/commons/dbcp/ Part of Jakarta’s Commons Designed to pool JDBC connections JakartaCommons Pool http://jakarta.apache.org/commons/pool/ A general-purpose set of APIs used to pool any type of object Under the Apache’s liberal license, it is available to learn and use Connection pools are configured by the Java EE server administrator Must be supported by the database driverDeveloped by Apache

Most JDBC vendors already have connection pooling facilities

Connection pooling Utilities

Jakarta Commons DBCP

http://jakarta.apache.org/commons/dbcp/

Part of Jakarta’s Commons

Designed to pool JDBC connections

JakartaCommons Pool

http://jakarta.apache.org/commons/pool/

A general-purpose set of APIs used to pool any type of object

Under the Apache’s liberal license, it is available to learn and use

Connection pools are configured by the Java EE server administrator

Must be supported by the database driver

Connection PoolingExplicitly close all connection objects try, catch and finally blockConnection con = null;Context context= new InitialContext(); try { DataSource ds = (DataSource)context.lookup("jdbc/wingsDB"); con = ds.getConnection(username, password)// here we write our codes } catch (Exception e) { System.out.println(“Exception Caught”);} Note: Codes are continuing in the Next Slide

Explicitly close all connection objects

try, catch and finally block

Connection Poolingfinally { if(con != null)con.close( ); }