Voici un petit exemple ;-) :

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import oracle.jdbc.pool.OracleDataSource;

public class AccesBD {
	
	private Connection connexion;
	private OracleDataSource ods;
	private static final String url = "jdbc:oracle:thin:USER/MDP@ADRESSE_BD";
	
	public AccesBD(){
		try{
			ods = new OracleDataSource();
	        ods.setURL(url);
	        connexion = ods.getConnection();
		}
		catch(SQLException se){
			System.out.println("Connexion impossible : "+se.getMessage());
		}
	}
	
	private void executeQuery(String query){
		try{
		Statement stmt = connexion.createStatement ();

		ResultSet rset = stmt.executeQuery (query);

		// Dump the result
		while (rset.next ())
		  System.out.println(rset.getString(1));
		}catch(Exception e){
			e.printStackTrace();
		}
	}
	
	public static void main(String[] args){
		AccesBD acces = new AccesBD();
		acces.executeQuery("select 'Hello JDBC: ' || sysdate from dual");
	}