Establishing Connections from JDBC to Databases

This section provides some quick information on establishing connections from JDBC to databases.

JDBC API offers two different ways to establish a connection to the database server:

1. Using DrirverManager Class: DriverManager.getConnection(connection_url) - The driver manager passes the connection URL to all loaded JDBC drivers, hoping that one of them will recognize the URL and creates a connection. See sample code below:

   // Loading a JDBC driver
   Class.forName("acme.db.Driver");

   // Creating a connection
   String url = "jdbc:odbc:fred";
   Connection con = DriverManager.getConnection(url,"user","pass");

2. Using DataSource Object: ds.getConnection() - A DataSource object should be configured and registered with a JNDI (Java Naming and Directory Interface) directory service only once. When a connection is needed, the registered DataSource object can be retrieved back from JNDI. A connection can be then created from the retrieved DataSource object.

   // Registering a DataSource
   VendorDataSource vds = new VendorDataSource();
   vds.setServerName("my_database_server");
   vds.setDatabaseName("my_database");
   vds.setDescription("the data source for inventory and personnel");
   Context ctx = new InitialContext();
   ctx.bind("jdbc/AcmeDB", vds);

   // Creating a connection
   Context ctx = new InitialContext();
   DataSource ds = (DataSource)ctx.lookup("jdbc/AcmeDB");
   Connection con = ds.getConnection("genius", "abracadabra");

JDK documentation suggests to use DataSource object to create connection objects whenever possible.

Table of Contents

 About This Book

JDBC (Java Database Connectivity) Introduction

 What Is JDBC?

 JDBC Version and History

 JDBC Driver Types

Establishing Connections from JDBC to Databases

 DriverManager - Loading JDBC Driver

 DriverManager - Connection URL

 JDK (Java SE) Installation

 Installing and Running Java DB - Derby

 Derby (Java DB) JDBC Driver

 Derby (Java DB) JDBC DataSource Objects

 Java DB (Derby) - DML Statements

 Java DB (Derby) - ResultSet Objects of Queries

 Java DB (Derby) - PreparedStatement

 Summary of JDBC Drivers and Database Servers

 Using Connection Pool with JDBC

 Archived Tutorials

 References

 Full Version in PDF/EPUB