JDBCとHibernate方式によるデータベースへのアクセスの簡単な例

1/jdbc方式でデータベースにアクセス

//        
Class.forName("com.mysql.jdbc.Driver");   
//        
Connection con = DriverManager.getConnection(   
  "jdbc:mysql://localhost:3306/demo", "test", "test");   
//        
Statement stmt = con.createStatement();   
//   SQL  ，        
ResultSet rs = stmt.executeQuery("SELECT * FROM person");   
//            
while (rs.next()) {   
 int id = rs.getInt("id");   
 String name = rs.getString("name");   
 Integer age = rs.getObject("age") == null ? null : rs.getInt("age");   
 System.out.println(id + ": " + name + " " + age);   
}   
//        
stmt.close();   
con.close();  

2/hibernate方式でデータベースにアクセス

sessionFactory = new Configuration().configure().buildSessionFactory();
		Session session=sessionFactory.openSession();
		Transaction trans=session.beginTransaction();
		trans.begin();
		//    HQL  
		Query query=session.createQuery("from Bike");
		Bike bike1=new Bike();
		bike1.setSerialNo(1);
		bike1.setFrame(2);
		bike1.setManufacturer("a");
		bike1.setModel("b");
		bike1.setStatus("7");
		bike1.setWeight(123.0);
		
		session.save(bike1);
		Iterator iterator=query.iterate();
		while(iterator.hasNext()){
			Bike bike=(Bike)iterator.next();
			System.out.println(bike);
		}
		trans.commit();
		session.close();