import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.SQLException;
 
public class OracleJDBC {
 
        public static void main(String[] argv) {
 
                DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
                System.out.println("-------- Oracle JDBC Connection Testing ------");
 
                try {
 
                        Class.forName("oracle.jdbc.driver.OracleDriver");
 
                } catch (ClassNotFoundException e) {
 
                        System.out.println("Where is your Oracle JDBC Driver?");
                        e.printStackTrace();
                        return;
 
                }
 
                System.out.println("Oracle JDBC Driver Registered!");
 
                Connection connection = null;
 
                try {
 
                        connection = DriverManager.getConnection(
                                        "jdbc:oracle:thin:@localhost:1521:mkyong", "username",
                                        "password");
 
                } catch (SQLException e) {
 
                        System.out.println("Connection Failed! Check output console");
                        e.printStackTrace();
                        return;
 
                }
 
                if (connection != null) {
                        System.out.println("You made it, take control your database now!");
                } else {
                        System.out.println("Failed to make connection!");
                }
        }
 
}

import java.sql.*; 
import oracle.jdbc.driver.*; 
import java.io.*;

class JdbcTest { 

 public static void main (String args []) throws SQLException { 

      final String PrepearedQuery = "SELECT rpad(id, 5, ' '), val FROM JTTable";

      // Load Oracle driver
      DriverManager.registerDriver (new oracle.jdbc.driver.OracleDriver());

      // Connect to the database
      Connection conn = DriverManager.getConnection 
                ("jdbc:oracle:thin:@127.0.0.1:1521:SID","USER","PASSWORD");
    
      // Query the test table 
      Statement stmt = conn.createStatement (); 
      ResultSet rset = stmt.executeQuery (PrepearedQuery);

      // Print the result set out 
      System.out.println();
      System.out.println("ID   VAL");

      while (rset.next ())
      {
         System.out.print   (rset.getString (1));
         System.out.println (rset.getString (2));
      }

      //close the result set, statement, and the connection
      rset.close();
      stmt.close();
      conn.close();
   } 
}