使用Eclipse或MyEclipse连接访问数…

使用Eclipse或MyEclipse连接访问数据库MySql的方法相同。

第一步：注册、连接

public final class JdbcUtils
{

private static
String url = "jdbc:mysql://localhost/jdbc";

private static String user = "root";

private static String password =
"123456";

private
JdbcUtils() {

}// 私有的构造方法，使该类不能在其他地方被实例化

static {//
静态代码块，类被加载的时候静态代码块被加载

try {

// 注册驱动

Class.forName("com.mysql.jdbc.Driver");

} catch (ClassNotFoundException
e) {

e.printStackTrace();

}

}

// 获得连接

public static Connection getConnection()
{

Connection
conn = null;

try {

conn =
DriverManager.getConnection(url, user, password);

} catch (SQLException e)
{

e.printStackTrace();

}

return
conn;

}

// 释放资源

public static void free(ResultSet rs, Statement
stmt, Connection conn) {

try {

if (rs !=
null) {

rs.close();

}

} catch (SQLException e)
{

e.printStackTrace();

} finally {

try {

if
(stmt != null) {

stmt.close();

}

} catch
(SQLException e) {

e.printStackTrace();

} finally
{

try
{

if
(conn != null) {

conn.close();

}

}
catch (SQLException e) {

e.printStackTrace();

}

}

}

}

}

第二步：创建实体类domain

public class User {

private int
id;

private String name;

private Date birthday;

private double 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 double
getMoney() {

return money;

}

public void
setMoney(double money) {

this.money = money;

}

public String
toString() {

return "学号="
+ id + "\t姓名=" + name + "\t生日=" + birthday + "\t工资="

+
money;

}

}

第三步：创建domain类的Dao接口

public interface UserDao
{

ArrayList
getAllUsers();

User getUserById(int id);

void create(User
u);

void update(User
u);

void delete(User
u);

}

第四步：编写Dao接口的实现类

public class UserDaoJdbcImpl
implements UserDao {

public void
create(User u) {

Connection
conn = null;

PreparedStatement ps =
null;

ResultSet rs = null;

try {

conn =
JdbcUtils.getConnection();

String
sql = "insert into user (name, birthday, money) values (?, ?,
?)";

ps
= conn.prepareStatement(sql);

ps.setString(1,
u.getName());

ps.setDate(2,
new java.sql.Date(u.getBirthday().getTime()));

ps.setDouble(3,
u.getMoney());

int
i = ps.executeUpdate();

System.out.println("成功向user表中插入"
+ i + "条记录");

} catch (SQLException e)
{

e.printStackTrace();

} finally {

JdbcUtils.free(rs,
ps, conn);

}

}

public void
delete(User u) {

Connection
conn = null;

PreparedStatement ps =
null;

ResultSet rs = null;

try {

conn =
JdbcUtils.getConnection();

String
sql = "delete from user where name = ?";

ps
= conn.prepareStatement(sql);

ps.setString(1,
u.getName());

int
i = ps.executeUpdate();

System.out.println("成功向user表中删除"
+ i + "条记录");

} catch (SQLException e)
{

e.printStackTrace();

} finally {

JdbcUtils.free(rs,
ps, conn);

}

}

public ArrayList
getAllUsers() {

Connection
conn = null;

PreparedStatement ps =
null;

ResultSet rs = null;

ArrayList
allUsers = new ArrayList();

User user = null;

try {

conn =
JdbcUtils.getConnection();

String
sql = "select * from user";

ps
= conn.prepareStatement(sql);

rs
= ps.executeQuery();

while
(rs.next()) {

user
= new User();

user.setId(rs.getInt("id"));

user.setName(rs.getString("name"));

user.setBirthday(rs.getDate("birthday"));

user.setMoney(rs.getDouble("money"));

allUsers.add(user);

}

} catch (SQLException e)
{

e.printStackTrace();

} finally {

JdbcUtils.free(rs,
ps, conn);

}

return allUsers;

}

public void
update(User u) {

Connection
conn = null;

PreparedStatement ps =
null;

ResultSet rs = null;

try {

conn =
JdbcUtils.getConnection();

String
sql = "update user set name = ?, birthday = ?, money = ? where
id=?";

ps
= conn.prepareStatement(sql);

User user =
getUserById(u.getId());

if
(u.getName() == null) {

u.setName(user.getName());

}

if
(u.getBirthday() == null) {

u.setBirthday(user.getBirthday());

}

if
(u.getMoney() == 0) {

u.setMoney(user.getMoney());

}

ps.setString(1,
u.getName());

ps.setDate(2,
new java.sql.Date(u.getBirthday().getTime()));

ps.setDouble(3,
u.getMoney());

ps.setInt(4,
u.getId());

int
i = ps.executeUpdate();

System.out.println("成功向user表中更新"
+ i + "条记录");

} catch (SQLException e)
{

e.printStackTrace();

} finally {

JdbcUtils.free(rs,
ps, conn);

}

}

public User
getUserById(int id) {

Connection
conn = null;

PreparedStatement ps =
null;

ResultSet rs = null;

User user =
null;

try {

conn =
JdbcUtils.getConnection();

String
sql = "select * from user where id = ?";

ps
= conn.prepareStatement(sql);

ps.setInt(1,
id);

rs
= ps.executeQuery();

if
(rs.next()) {

user
= new User();

user.setId(rs.getInt("id"));

user.setName(rs.getString("name"));

user.setBirthday(rs.getDate("birthday"));

user.setMoney(rs.getDouble("money"));

}

} catch (SQLException e)
{

e.printStackTrace();

} finally {

JdbcUtils.free(rs,
ps, conn);

}

return
user;

}

}

第五步：编写Dao测试类

public class UserDaoTest
{

public static
void main(String[] args) {

//
create();

//
update();

//
delete();

//
getAllUsers();

getUserById();

}

static void
getAllUsers() {

UserDao ud =
new UserDaoJdbcImpl();

ArrayList
allUsers = ud.getAllUsers();

for (User u :
allUsers) {

System.out.println(u);

}

}

static void
create() {

UserDao ud =
new UserDaoJdbcImpl();

User user =
new User();

user.setName("老师");

Date d =
null;

try {

SimpleDateFormat
sdf = new SimpleDateFormat("yyyy-MM-dd");

d =
sdf.parse("1999-2-3");

} catch (ParseException e)
{

e.printStackTrace();

}

user.setBirthday(d);

user.setMoney(123);

ud.create(user);

}

static void
update() {

UserDao ud =
new UserDaoJdbcImpl();

User user =
new User();

user.setId(9);

user.setName("老师");

Date d =
null;

try {

SimpleDateFormat
sdf = new SimpleDateFormat("yyyy-MM-dd");

d =
sdf.parse("1999-9-14");

} catch (ParseException e)
{

e.printStackTrace();

}

user.setBirthday(d);

user.setMoney(1234);

ud.update(user);

}

static void
delete() {

UserDao ud =
new UserDaoJdbcImpl();

User user =
new User();

user.setName("老师");

ud.delete(user);

}

static void
getUserById() {

UserDao ud =
new UserDaoJdbcImpl();

User user =
ud.getUserById(9);

System.out.println(user);

}

}