JDBC的基本操作

package com.lxf.domain:

package com.lxf.domain;

import java.util.Date;

public class User {
    private int id;
    private String name;
    private Date birthday;
    private float money;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public Date getBirthday() {
        return birthday;
    }
    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }
    public float getMoney() {
        return money;
    }
    public void setMoney(float money) {
        this.money = money;
    }
    public String toString(){
	String information = getId()+"    "+getName()+"    "+getBirthday()+"    "+getMoney();
	return information;
    }
}

package com.lxf.dao:
异常类：

package com.lxf.dao;

public class DaoException extends RuntimeException{
    private static final long serialVersionUID = 1L;
    public DaoException(){}
    public DaoException(String message){
	super(message);
    }
    public DaoException(Throwable cause){
	super(cause);
    }
    public DaoException(String message,Throwable cause){
	super(message,cause);
    }
}

工厂模式工厂类：

package com.lxf.dao;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

public class DaoFactory {
    private static UserDao userDao = null;
    private static DaoFactory instance = new DaoFactory();

    private DaoFactory() {
	try (InputStream inStream = DaoFactory.class.getClassLoader()
		.getResourceAsStream("daoconfig.properties")) {

	    Properties prop = new Properties();
	    prop.load(inStream);

	    String userDaoClass = prop.getProperty("userDaoClass");
	    userDao = (UserDao) Class.forName(userDaoClass).newInstance();

	} catch (ClassNotFoundException | InstantiationException
		| IllegalAccessException | IOException e) {
	    throw new ExceptionInInitializerError(e);
	}
    }

    public static DaoFactory getInstance() {
	return instance;
    }

    public UserDao getUserDao() {
	return userDao;
    }
}

工厂类的daoconfig.properties文件：

userDaoClass=com.lxf.dao.impl.UserDaoJdbcImpl

接口:

package com.lxf.dao;

import com.lxf.domain.User;

public interface UserDao {
    //增加用户
    public void addUser(User user);
    //根据Id获取用户
    public User getUser(int userId);
    //根据用户名获取用户
    public User findUser(String loginName);
    //更新用户
    public void update(User user);
    //删除用户
    public boolean delete(User user);
}

package com.lxf.dao.impl:
接口的实现：

package com.lxf.dao.impl;

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

import com.lxf.dao.DaoException;
import com.lxf.dao.UserDao;
import com.lxf.domain.User;
import com.lxf.jdbc.JdbcUtils;

public class UserDaoJdbcImpl implements UserDao {

    @Override
    public void addUser(User user) {
	String sql = "insert into user(name,birthday,money)values(?,?,?)";
	try (Connection conn = JdbcUtils.getConnection();
		PreparedStatement ps = conn.prepareStatement(sql)) {
	    ps.setString(1, user.getName());
	    ps.setDate(2, new java.sql.Date(user.getBirthday().getTime()));
	    ps.setFloat(3, user.getMoney());
	    ps.executeUpdate();
	} catch (SQLException e) {
	    throw new DaoException(e.getMessage(), e);
	}
    }

    @Override
    public User getUser(int userId) {
	User user = null;
	String sql = "select id,name,birthday,money from user where id=?";
	try (PreparedStatement ps = JdbcUtils.getConnection().prepareStatement(
		sql);) {
	    // 处理结果
	    ps.setInt(1, userId);
	    try (ResultSet rs = ps.executeQuery();) {
		while (rs.next()) {
		    user = mappingUser(rs);
		}
	    } catch (SQLException e) {
		throw new DaoException(e.getMessage(), e);
	    }
	} catch (SQLException e) {
	    throw new DaoException(e.getMessage(), e);
	}
	return user;
    }

    @Override
    public User findUser(String loginName) {
	User user = null;
	String sql = "select id,name,birthday,money from user where name=?";
	try (PreparedStatement ps = JdbcUtils.getConnection().prepareStatement(
		sql);) {
	    ps.setString(1, loginName);
	    try (ResultSet rs = ps.executeQuery()) {
		while (rs.next()) {
		    user = mappingUser(rs);
		}
	    } catch (SQLException e) {
		throw new DaoException(e.getMessage(), e);
	    }
	} catch (SQLException e) {
	    throw new DaoException(e.getMessage(), e);
	}
	return user;
    }

    @Override
    public void update(User user) {
	String sql = "update user set name=?,birthday=?,money=? where id=?";
	try (PreparedStatement ps = JdbcUtils.getConnection().prepareStatement(
		sql);) {
	    ps.setString(1, user.getName());
	    ps.setDate(2, new java.sql.Date(user.getBirthday().getTime()));
	    ps.setFloat(3, user.getMoney());
	    ps.setInt(4, user.getId());
	    ps.executeUpdate();// 执行语句,返回受影响的行数
	} catch (Exception e) {
	    throw new DaoException(e.getMessage(), e);
	}
    }

    @Override
    public boolean delete(User user) {
	boolean flag = false;
	String sql = "delete from user where id=" + user.getId();
	try (Connection conn = JdbcUtils.getConnection();
		Statement st = conn.createStatement();) {
	    int i = st.executeUpdate(sql); // 执行语句,返回受影响的行数
	    if (i >= 0) {
		flag = true;
	    }
	} catch (SQLException e) {
	    throw new DaoException(e.getMessage(), e);
	}
	return flag;
    }

    private User mappingUser(ResultSet rs) throws SQLException {
	User user;
	user = new User();
	user.setId(rs.getInt("id"));
	user.setName(rs.getString("name"));
	user.setBirthday(rs.getDate("birthday"));
	user.setMoney(rs.getFloat("money"));
	return user;
    }
}

一个简单的测试类：

package com.lxf.dao;

import java.util.Date;

import com.lxf.dao.impl.UserDaoJdbcImpl;
import com.lxf.domain.User;

public class UserDaoTest {
    public static void main(String[]args){
	UserDao userDao = DaoFactory.getInstance().getUserDao();
	sop(userDao.getUser(1));
    }
    public static void sop(Object obj){
	System.out.println(obj);
    }
}

代码有点基础，贴出来怕自己忘记，没有贴出数据库连接代码。在上一篇博客。
如果发现有需要更改的地方，请及时指出，我不胜感激。