8-----spring整合mybatis

直接上手

导包

　　<dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>5.2.1.RELEASE</version>
        </dependency>
        
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.10.RELEASE</version>
        </dependency>
        
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.2</version>
        </dependency>
        
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
        </dependency>
        
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13</version>
        </dependency>
        
    </dependencies>

 写一下实体类

package com.sicheng.pojo;

public class User {

    private int id;
    private String name;
    private String pwd;

    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 String getPwd() {
        return pwd;
    }

    public void setPwd(String pwd) {
        this.pwd = pwd;
    }

    public User(int id, String name, String pwd) {
        this.id = id;
        this.name = name;
        this.pwd = pwd;
    }

    public User() {
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", pwd='" + pwd + '\'' +
                '}';
    }
}

 

建立数据库

配置mybatis

原来的配置

现在的配置-----除了设置，就基本不配置

 

 

 编写映射文件usermapper

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.sicheng.dao.UserMapper">
    <select id="selectUser" resultType="User">
        select * from user;
    </select>
</mapper> 

编写UserMapper接口

package com.sicheng.dao;

import com.sicheng.pojo.User;

import java.util.List;

public interface UserMapper {

    public List<User> selectUser();
}

编写UserMapper的实现类

package com.sicheng.dao;

import com.sicheng.pojo.User;
import org.apache.ibatis.session.SqlSession;
import org.mybatis.spring.SqlSessionTemplate;

import java.util.List;

public class UserDaoImpl implements UserMapper {

    private SqlSessionTemplate sqlSession;

    public void setSqlSession(SqlSessionTemplate sqlSession) {
        this.sqlSession = sqlSession;
    }

    public List<User> selectUser() {
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.selectUser();
    }

}

 

你应该看到了注入吧！！！！！

回顾一下mybatis的流程

1. 创建SqlSessionFactory对象
2. 开启一个会话，也就是返回一个SQLSession对象

那么：

• SqlsessionFactory是通过mybatis-config文件建立的，那么就需要一个datasource类，还有配置的mapper路径；配置的时候注入一下就完事了
• SqlSession对象是通过SqlSessionFactory构造的。
• UserDao中注入了一个SqlSession

所以配置文件spring

 

 除了删除过程

Spring提供了一个类，SqlSessionDaoSupport，这个类是默认注册了的。

接收一个SqlSessionFactory，然后就可以返回一个SqlSession

public class UserDaoImpl extends SqlSessionDaoSupport implements UserMapper {
   public List<User> selectUser() {
       UserMapper mapper = getSqlSession().getMapper(UserMapper.class);
       return mapper.selectUser();
  }
}

配置文件