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copied!<p>Let's decode the lines of your code block:</p> <pre><code>1. DriverManager.registerDriver 2. (new oracle.jdbc.driver.OracleDriver()); 3. conn = java.sql.DriverManager.getConnection( 4. "jdbc:oracle:thin:username/password@machine.us.company.com:1234:dbSID"); </code></pre> <p>Line 2: </p> <p>Creates a new instance of <code>oracle.jdbc.driver.OracleDriver</code>, a JDBC <code>Driver</code> for the Oracle database. A JDBC driver implements the interfaces and classes defined by the JDBC API that programmers use to connect to a database and perform queries. </p> <p>Line 1</p> <p>Registers the instance of the <code>oracle.jdbc.driver.OracleDriver</code> to the <a href="http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html" rel="nofollow noreferrer"><code>DriverManager</code></a> class which is the traditional management layer of JDBC, working between the user and the drivers. It handles establishing a connection between a database and the appropriate driver. </p> <p>Line 3:</p> <p>Now that the communication layer between the JDBC application and the database is ready, you can create a connection by calling <a href="http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html#getConnection%28java.lang.String%29" rel="nofollow noreferrer"><code>getConnection()</code></a> method of the <a href="http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html" rel="nofollow noreferrer"><code>DriverManager</code></a> class.</p> <p>Line 4:</p> <p>This is the "connection string" or "database URL". This <code>String</code> identifies the database you want to connect to. The scheme of this URL is specific to the database provider and/or the driver (here, Oracle and its "thin" driver). </p> <hr> <p>Note that prior to Java 6, calling <code>Class.forName</code> was the preferred way to load and register a JDBC Driver. It was the responsibility of the <code>Driver</code> to call <a href="http://java.sun.com/javase/6/docs/api/java/sql/DriverManager.html#registerDriver%28java.sql.Driver%29" rel="nofollow noreferrer"><code>DriverManager.registerDriver</code></a>. </p> <blockquote> <p>[...] All <code>Driver</code> classes should be written with a static section (a static initializer) that creates an instance of the class and then registers it with the <code>DriverManager</code> class when it is loaded. Thus, a user would not normally call <code>DriverManager.registerDriver</code> directly; it should be called automatically by a <code>Driver</code> class when it is loaded.</p> </blockquote> <p>Check the <a href="http://java.sun.com/j2se/1.5.0/docs/guide/jdbc/getstart/drivermanager.html" rel="nofollow noreferrer">Driver Manager</a> chapter from the JDBC documentation for more details.</p>

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