Loading JDBC Driver Class

JDBC for Oracle - Herong's Tutorial Examples

∟Loading JDBC Driver Class - ojdbc16.jar

This section describes how to load the Oracle JDBC driver class - ojdbc14.jar.

If you are using newer versions of JDK, it will automatically load the Oracle JDBC driver, as long as the JAR file is included in the classpath. There is no need to call Class.forName("oracle.jdbc.OracleDriver") to load the driver class explicitly.

Here is a tutorial program to show you how JDK loads the Oracle JDBC driver:

/* OracleLoadDriver.java
 * Copyright (c) HerongYang.com. All Rights Reserved.
 */
import java.sql.*;
import java.util.*;
public class OracleLoadDriver {
  public static void main(String [] args) {
    Connection con = null;
    try {

      System.out.println("Before loading OracleDriver:");
      listDrivers();

// Load the Oracle JDBC driver with forName()
      Class.forName("oracle.jdbc.OracleDriver") ;

      System.out.println("After loading OracleDriver:");
      listDrivers();

    } catch (Exception e) {
      e.printStackTrace();
    }
  }
  private static void listDrivers() {
    Enumeration driverList = DriverManager.getDrivers();
    while (driverList.hasMoreElements()) {
      Driver driverClass = (Driver) driverList.nextElement();
      System.out.println("   "+driverClass.getClass().getName());
    }
  }
}

The compilation and execution of the above program were recorded below. Notice the exception error I got without ojdbc11.jar in the classpath:

herong> javac OracleLoadDriver.java

herong> java OracleLoadDriver

Before loading OracleDriver:
java.lang.ClassNotFoundException: oracle.jdbc.OracleDriver
   ...

herong> java -cp .;ojdbc11.jar OracleLoadDriver

Before loading OracleDriver:
   oracle.jdbc.OracleDriver
After loading OracleDriver:
   oracle.jdbc.OracleDriver

Depending what versions of JDK and Oracle server you are using, you may need use different versions of Oracle JDBC driver JAR file in the class path option, "-cp ...".