Java EE框架

1、表现层 springMVC

2、粘合剂 spring(IOC/控制反转 AOP/面向切面编程 DI/依赖注入)

3、持久层 mybatis

Dao模式创建mybatis项目过程

1、下载jar包

mybatis jar包下载地址：

链接：https://pan.baidu.com/s/1xvZauxhkAPYxWvoJuxlLFg

提取码：ia7w

复制这段内容后打开百度网盘手机App，操作更方便哦

mybatis中文手册地址：

http://www.dba.cn/book/mybatis/MYBATISZhongWenShouCe/MYBATISXMLPeiZhi.html

2、导入所需要的jar包

commons-logging-1.2.jar 用于日志处理

log4j-1.2.17.jar 日志系统，负责日志输出

mybatis-3.5.0.jar mybatis核心jar包

mysql-connector-java-5.1.46.jar MySQL数据库驱动jar包

将jar包部署到项目中

3、编写mybatis核心配置文件

创建mybatis核心配置文件mybatis-config.xml

创建Java属性配置文件jdbc.properties

创建日志属性配置文件log4j.properties

mybatis-config.xml

/p>

"mybatis-3-config.dtd" >

jdbc.properties

jdbc.DriverClassName=com.mysql.jdbc.Driver

jdbc.url=jdbc:mysql://localhost:3306/数据库名?characterEncoding=utf-8

jdbc.username=用户名

jdbc.password=密码

log4j.properties

log4j.rootLogger=DEBUG, Console

#Console

log4j.appender.Console=org.apache.log4j.ConsoleAppender

log4j.appender.Console.layout=org.apache.log4j.PatternLayout

log4j.appender.Console.layout.ConversionPattern=%d [%t] %-5p [%c] - %m%n

log4j.logger.java.sql.ResultSet=INFO

log4j.logger.org.apache=INFO

log4j.logger.java.sql.Connection=DEBUG

log4j.logger.java.sql.Statement=DEBUG

log4j.logger.java.sql.PreparedStatement=DEBUG

4、创建实体类

创建实体类并生成seter/geter方法重写toString方法。

User.java

package com.model;

public class User {

private int userId;

private String userName;

private String userPass;

private int userSex;

private int userAge;

public int getUserId() {

return userId;

}

public void setUserId(int userId) {

this.userId = userId;

}

public String getUserName() {

return userName;

}

public void setUserName(String userName) {

this.userName = userName;

}

public String getUserPass() {

return userPass;

}

public void setUserPass(String userPass) {

this.userPass = userPass;

}

public int getUserSex() {

return userSex;

}

public void setUserSex(int userSex) {

this.userSex = userSex;

}

public int getUserAge() {

return userAge;

}

public void setUserAge(int userAge) {

this.userAge = userAge;

}

@Override

public String toString() {

return "User [userId=" + userId + ", userName=" + userName + ", userPass=" + userPass + ", userSex=" + userSex

+ ", userAge=" + userAge + "]";

}

}

5、创建Dao接口

UserDao.java

package com.dao;

import com.model.User;

public interface UserDao {

public User findUserById(int Id);

//通过id查询用户信息

public void addUser(User user);

//向数据库中增加用户信息

public void deleteUser(int Id);

//删除用户信息

public void updateUser(User user);

//修改用户信息

}

userService.java

package com.service;

import com.model.User;

public interface userService {

public User findUserById(int Id);

public void addUser(User user);

public void deleteUser(int Id);

public void updateUser(User user);

}

6、创建 sql 映射文件

在dao包下创建sql映射文件 UserDao.xml。这里使用mapper动态代理所以映射文件必须和接口UserDao.java在同一个包下。

select * from userdb where userId=#{Id}

insert into userdb (userName,userPass,userSex,userAge)

values (#{userName},#{userPass},#{userSex},#{userAge})

delete from userdb where userId=#{value}

update userdb set userName=#{userName},userPass=#{userPass},userSex=#{userSex},userAge=#{userAge}

where userId=#{userId}

7、单例模式创建SqlSessionFactory工厂

MyBatisUtilsLazy.java

package com.utils;

import java.io.InputStream;

import org.apache.ibatis.io.Resources;

import org.apache.ibatis.session.SqlSessionFactory;

import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class MyBatisUtilsLazy {

public static SqlSessionFactory factory=null;

public static SqlSessionFactory getFactory() {

if (factory==null) {

InputStream in;

try {

synchronized(MyBatisUtilsLazy.class){

if (factory==null) {

in =Resources.getResourceAsStream("mybatis-config.xml");

factory = new SqlSessionFactoryBuilder().build(in);

}

}

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

return factory;

}

}

8、编写实现类

UserServiceImpl.java

package com.service.impl;

import org.apache.ibatis.session.SqlSession;

import com.dao.UserDao;

import com.model.User;

import com.service.userService;

import com.utils.MyBatisUtilsLazy;

public class UserServiceImpl implements userService {

SqlSession session = MyBatisUtilsLazy.getFactory().openSession();

UserDao mapper = session.getMapper(UserDao.class);

@Override

public User findUserById(int Id) {

// TODO Auto-generated method stub

return mapper.findUserById(Id);

}

@Override

public void addUser(User user) {

// TODO Auto-generated method stub

try {

mapper.addUser(user);

session.commit();

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}finally {

session.close();

}

}

@Override

public void deleteUser(int Id) {

// TODO Auto-generated method stub

try {

mapper.deleteUser(Id);

session.commit();

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}finally {

session.close();

}

}

@Override

public void updateUser(User user) {

// TODO Auto-generated method stub

try {

mapper.updateUser(user);

session.commit();

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}finally {

session.close();

}

}

}

9、编写测试类

TestAddUser.java

package com.test;

import org.junit.Test;

import com.model.User;

import com.service.impl.UserServiceImpl;

public class TestAddUser {

@Test

public void testAddUser() {

UserServiceImpl userServiceImpl = new UserServiceImpl();

User user = new User();

String userName="aaa";

String userPass="152425";

int userSex=0;

int userAge=28;

user.setUserName(userName);

user.setUserPass(userPass);

user.setUserSex(userSex);

user.setUserAge(userAge);

userServiceImpl.addUser(user);

System.out.println(user);

}

}

TestDeleteUser.java

package com.test;

import org.junit.Test;

import com.service.impl.UserServiceImpl;

public class TestDeleteUser {

@Test

public void testdeleteUser() {

UserServiceImpl userServiceImpl = new UserServiceImpl();

int Id=16;

userServiceImpl.deleteUser(Id);

}

}

TestFindUserById.java

package com.test;

import org.junit.jupiter.api.Test;

import com.model.User;

import com.service.impl.UserServiceImpl;

public class TestFindUserById {

@Test

public void testFindUserById(){

UserServiceImpl userServiceImpl = new UserServiceImpl();

int Id=17;

User user = userServiceImpl.findUserById(Id);

System.out.println(user);

}

}

TestUpdateUser.java

package com.test;

import org.junit.Test;

import com.model.User;

import com.service.impl.UserServiceImpl;

public class TestUpdateUser {

@Test

public void testupdateUser() {

UserServiceImpl userServiceImpl = new UserServiceImpl();

User user = new User();

String userName="张三";

String userPass="152425";

int userSex=0;

int userAge=25;

user.setUserId(18);

user.setUserName(userName);

user.setUserPass(userPass);

user.setUserSex(userSex);

user.setUserAge(userAge);

userServiceImpl.updateUser(user);

System.out.println(user);

}

}