long start = System.currentTimeMillis();
PoolDataSource pds = PoolDataSourceFactory.getPoolDataSource();
System.out.println("getPoolDataSource: " + (System.currentTimeMillis() - start));
start = System.currentTimeMillis();
pds.setConnectionFactoryClassName("oracle.jdbc.pool.OracleDataSource");
pds.setURL("jdbc:oracle:thin:@//oraclewin:1521/MyDB");
pds.setUser("user");
pds.setPassword("pass");
pds.setInitialPoolSize(0);
System.out.println("Init DataSource: " + (System.currentTimeMillis() - start));
start = System.currentTimeMillis();
Connection con1 = pds.getConnection();
System.out.println("getConnection1: " + (System.currentTimeMillis() - start));
start = System.currentTimeMillis();
Connection con2 = pds.getConnection();
System.out.println("getConnection2: " + (System.currentTimeMillis() - start));

getPoolDataSource: 451
Init DataSource: 17
getConnection1: 3008
getConnection2: 123

getPoolDataSource: 2370
getConnection1: 26795
getConnection2: 10979