JDBC for Oracle - Herong's Tutorial Examples - v3.13, by Herong Yang
Connection Pooling with Commons DBCP BasicDataSource
This section provides a tutorial example that shows you how to use the Commons DBCP BasicDataSource class to manage the connection pool with JavaBean style properties.
The easiest way to use Commons DBCP package for connection pooling is to use the org.apache.commons.dbcp2.BasicDataSource class. It implements the standard JDBC javax.sql.DataSource interface to manage the connection pool with JavaBean style properties.
The BasicDataSource class uses set*() and get*() methods to configure and manage the connection pool. Here is my sample Java program, DbcpBasicDataSourceTest.java against my local Oracle server.
/* DbcpBasicDataSourceTest.java * Copyright (c) HerongYang.com. All Rights Reserved. */ import java.sql.Connection; import java.sql.DatabaseMetaData; import javax.sql.DataSource; import org.apache.commons.dbcp2.BasicDataSource; public class DbcpBasicDataSourceTest { static java.io.PrintStream out = System.out; public static void main(String[] args) throws Exception { String url = "jdbc:oracle:thin:Herong/TopSecret@//localhost:1521/XE"; // Get a DataSource with pooled connections DataSource ds = getDataSource(url); // Get a pooled connection Connection con = ds.getConnection(); checkDataSource(ds); // Verify the pooled connection DatabaseMetaData meta = con.getMetaData(); out.println(); out.println("Database Connection Info: "); out.println(" Server name: "+meta.getDatabaseProductName()); out.println(" Server version: "+meta.getDatabaseProductVersion()); out.println(" Driver name: "+ meta.getDriverName()); out.println(" Driver version: "+ meta.getDriverVersion()); out.println(" JDBC major version: "+ meta.getJDBCMajorVersion()); out.println(" JDBC minor version: "+ meta.getJDBCMinorVersion()); // Close the pooled connection con.close(); // Wait for 3 minutes to check the server side out.println(); out.println("Go and count connections on the database server ..."); Thread.sleep(3*60*1000); // Close the DataSource closeDataSource(ds); } public static DataSource getDataSource(String url) throws Exception { BasicDataSource bds = new BasicDataSource(); bds.setUrl(url); bds.setInitialSize(10); DataSource ds = (DataSource) bds; return ds; } public static void closeDataSource(DataSource ds) throws Exception { BasicDataSource bds = (BasicDataSource) ds; bds.close(); } public static void checkDataSource(DataSource ds) { BasicDataSource bds = (BasicDataSource) ds; out.println(); out.println("DBCP BasicDataSource Info: "); out.println(" Active Connections: " + bds.getNumActive()); out.println(" Idle Connections: " + bds.getNumIdle()); out.println(" Connection URL: " + bds.getUrl()); out.println(" Driver Class: " + bds.getDriverClassName()); out.println(" User Name: " + bds.getUsername()); out.println(" Password: " + bds.getPassword()); } }
To run this test program, I need 4 JAR files. See other tutorials to download them.
Let's run it:
herong> java -cp .:\ commons-dbcp2-2.8.0.jar:\ commons-pool2-2.10.0.jar:\ commons-logging-1.2.jar:\ ojdbc11.jar \ DbcpBasicDataSourceTest.java DBCP BasicDataSource Info: Active Connections: 1 Idle Connections: 7 Connection URL: jdbc:oracle:thin:Herong/TopSecret@//localhost:1521/XE Driver Class: null User Name: null Password: null Database Connection Info: Server name: Oracle Server version: Oracle Database 21c Express Edition Release ... Driver name: Oracle JDBC driver Driver version: 21.4.0.0.0 JDBC major version: 4 JDBC minor version: 3 Go and count connections on the database server ...
On the Oracle server, log in as "root". I see 8 connections:
SQL> SELECT sid, SUBSTR(username,0,8) FROM v$session WHERE username IS NOT NULL; SID SUBSTR(USERNAME,0,8) ---------- -------------------------------- 12 HERONG 137 HERONG 263 HERONG 379 SYS 380 HERONG 507 HERONG 630 HERONG 754 HERONG 874 HERONG 9 rows selected.
So, what we can see from this tutorial:
Table of Contents
JDBC (Java Database Connectivity) Introduction
Oracle Express Edition Installation on Windows
Oracle - Reference Implementation of JdbcRowSet
Oracle - JBDC CallableStatement
Oracle CLOB (Character Large Object) - TEXT
Oracle BLOB (Binary Large Object) - BLOB
►Using Connection Pool with JDBC
What Is Database Connection Pool
Commons DBCP for Connection Pooling
►Connection Pooling with Commons DBCP BasicDataSource
Connection Pooling with Commons DBCP PoolingDriver
Connection Pooling with C3P0 ComboPooledDataSource