Spring JDBC

1.Customer 表

CREATE TABLE `customer` (
  `CUST_ID` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `NAME` varchar(100) NOT NULL,
  `AGE` int(10) unsigned NOT NULL,
  PRIMARY KEY (`CUST_ID`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

2. Customer模型

public class Customer 
{
    int custId;
    String name;
    int age;
    //getter and setter methods
    
}

3.数据访问对象 (DAO) 模式

public interface CustomerDAO 
{
    public void insert(Customer customer);
    public Customer findByCustomerId(int custId);
}

public class JdbcCustomerDAO implements CustomerDAO
{
    private DataSource dataSource;
    
    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }
    
    public void insert(Customer customer){
        
        String sql = "INSERT INTO CUSTOMER " +
                "(CUST_ID, NAME, AGE) VALUES (?, ?, ?)";
        Connection conn = null;
        
        try {
            conn = dataSource.getConnection();
            PreparedStatement ps = conn.prepareStatement(sql);
            ps.setInt(1, customer.getCustId());
            ps.setString(2, customer.getName());
            ps.setInt(3, customer.getAge());
            ps.executeUpdate();
            ps.close();
            
        } catch (SQLException e) {
            throw new RuntimeException(e);
            
        } finally {
            if (conn != null) {
                try {
                    conn.close();
                } catch (SQLException e) {}
            }
        }
    }
    
    public Customer findByCustomerId(int custId){
        
        String sql = "SELECT * FROM CUSTOMER WHERE CUST_ID = ?";
        
        Connection conn = null;
        
        try {
            conn = dataSource.getConnection();
            PreparedStatement ps = conn.prepareStatement(sql);
            ps.setInt(1, custId);
            Customer customer = null;
            ResultSet rs = ps.executeQuery();
            if (rs.next()) {
                customer = new Customer(
                    rs.getInt("CUST_ID"),
                    rs.getString("NAME"), 
                    rs.getInt("Age")
                );
            }
            rs.close();
            ps.close();
            return customer;
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } finally {
            if (conn != null) {
                try {
                conn.close();
                } catch (SQLException e) {}
            }
        }
    }
}

4.Spring bean配置

5.main方法

public class App 
{
    public static void main( String[] args )
    {
        ApplicationContext context = 
            new ClassPathXmlApplicationContext("applicationContext.xml");
         
        CustomerDAO customerDAO = (CustomerDAO) context.getBean("customerDAO");
        Customer customer = new Customer(1, "小明",29);
        customerDAO.insert(customer);
        
        Customer customer1 = customerDAO.findByCustomerId(1);
        System.out.println(customer1);
        
    }
}