无法通过Java与Oracle 11g连接

我试图通过Java与Oracle 11g进行连接，并且添加了o​​jdbc14和ojdbc6，但在编译时仍然出现此错误。请提供帮助。

        java.lang.ClassNotFoundException: com.oracle.jdbc.Driver
         Goodbye!
            at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
            at java.net.URLClassLoader.findClass(Unknown Source)
            at java.lang.ClassLoader.loadClass(Unknown Source)
            at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
            at java.lang.ClassLoader.loadClass(Unknown Source)
            at java.lang.Class.forName0(Native Method)
            at java.lang.Class.forName(Unknown Source)
            at JDBC.main(JDBC.java:21)

我的代码是

        import java.sql.*;


        public class JDBC {

         public static void main(String[] args) {
           Connection conn = null;
            Statement stmt = null;

打开连接

           try{
        Class.forName("com.oracle.jdbc.Driver");


          System.out.println("Connecting to database...");

           conn = DriverManager.getConnection
          ("jdbc:oracle:thin:@172.16.209.169:1521:heritage", "USERNAME", "PASSWORD");

     }catch(SQLException se){

          se.printStackTrace();
       }catch(Exception e){

处理Class.forName的错误

          e.printStackTrace();
       }finally{

         try{
             if(conn!=null)
                conn.close();
          }catch(SQLException se){
             se.printStackTrace();
          }
       }
       System.out.println("Goodbye!");
    }