Connect to Oracle DB - Java

import java.sql.*;

public class OracleTest {

	String dbUrl = "jdbc:oracle:thin:@()";

	String theUser = "";

	String thePw = "";

	Connection conn = null;
	Statement stmt;
	ResultSet rs = null;

	public OracleTest() {
		try {
			Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();

			conn = DriverManager.getConnection(dbUrl, theUser, thePw);
			stmt = conn.createStatement();

			System.out.println("------------------------------");
			System.out.println("DatabaseProductVersion: "
					+ conn.getMetaData().getDatabaseProductVersion());
			System.out.println("DriverVersion: "
					+ conn.getMetaData().getDriverVersion());
			System.out.println("------------------------------");

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

	public ResultSet executeQuery(String sql) {
		rs = null;
		try {
			rs = stmt.executeQuery(sql);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return rs;
	}

	public void close() {
		try {
			conn.close();
			conn.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	public static void main(String[] args) {
		ResultSet newrs;
		OracleTest newjdbc = new OracleTest();
		newrs = newjdbc.executeQuery("select * from dual");

		try {
			while (newrs.next()) {
				System.out.print(newrs.getString(1));
			}

		} catch (Exception e) {
			e.printStackTrace();
		}
		newjdbc.close();
	}
}