JDBC 4.0 and Oracle JDeveloper for J2EE Development
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Automatic SQL Driver Loading

JDBC 4.0 has facilitated the loading of a JDBC driver. In JDBC 3.0, a JDBC driver is loaded with the Class.forName(String) method. The Oracle JDBC driver is loaded in the following manner:

Class.forName("oracle.jdbc.OracleDriver");

In JDBC 4.0, a JDBC driver is loaded automatically with the Java Standard Edition Service Provider mechanism. The JDBC driver is loaded when the java.sql.DriverManager.getConnection() method is invoked. To load a JDBC driver with the Service Provider mechanism, JDBC 4.0 drivers should include the META-INF/services/java.sql.Driver file. In the java.sql.Driver file, specify the JDBC driver class to load. If the oracle.jdbc.OracleDriver is to be loaded then specify the following line in the java.sql.Driver file:

oracle.jdbc.OracleDriver

Multiple driver classes can be specified in a java.sql.Driver file, each on a separate line. A list of JDBC drivers available to a DriverManager can be obtained with the getDrivers() method:

Enumeration<Driver> drivers=DriverManager.getDrivers();

A JDBC connection can be obtained using the getConnection() method of the DriverManager class:

String url="jdbc:oracle:thin:@localhost:1521:ORCL";
Connection connection = DriverManager.getConnection(url,"oe", "pw");