构建Mybatis架构

构建Mybatis架构

1，点击新建model，选择maven不适用骨架，直接next，创建并加载文件
2，在pom.xml文件中导入

    <dependencies>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.22</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.3</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.14</version>
        </dependency>
    </dependencies>

3，src/main/java目录下创建domain和dao包并写入方法

package domain;

import java.io.Serializable;
import java.util.Date;

public class User implements Serializable {
    private Integer id;
    private String username;
    private Date birthday;
    private String sex;
    private String address;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id=id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username=username;
    }

    public Date getBirthday() {
        return birthday;
    }

    public void setBirthday(Date birthday) {
        this.birthday=birthday;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex=sex;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address=address;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", username='" + username + '\'' +
                ", birthday=" + birthday +
                ", sex='" + sex + '\'' +
                ", address='" + address + '\'' +
                '}';
    }
}

package dao;
import domain.User;
import java.util.List;
public interface UserDao {
    List<User> findAll();
}

4，在src项目下导入配置文件SqlMapConfig.xml，log4j.properties

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <!--配置环境-->
    <environments default="mysql">
        <!--配置mysql环境-->
        <environment id="mysql">
            <!--配置事务类型-->
            <transactionManager type="JDBC"></transactionManager>
           <!--配置数据源(连接池)-->
            <dataSource type="POOLED">
                <!--配置连接数据库的基本信息-->
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis?serverTimezone=Asia/Shanghai"/>
                <property name="username" value="root"/>
                <property name="password" value="root"/>
            </dataSource>
        </environment>
    </environments>
    <!--指定映射配置文件的位置，映射配置文件指的是每个dao独立的配置文件-->
    <mappers>
        <mapper resource="dao/UserDao.xml/"/>
    </mappers>
</configuration>

### 设置###
log4j.rootLogger = debug,stdout,D,E
 
### 输出信息到控制抬 ###
log4j.appender.stdout = org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target = System.out
log4j.appender.stdout.layout = org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern = [%-5p] %d{yyyy-MM-dd HH:mm:ss,SSS} method:%l%n%m%n
 
### 输出DEBUG 级别以上的日志到=E://logs/error.log ###
log4j.appender.D = org.apache.log4j.DailyRollingFileAppender
log4j.appender.D.File = E://logs/log.log
log4j.appender.D.Append = true
log4j.appender.D.Threshold = DEBUG 
log4j.appender.D.layout = org.apache.log4j.PatternLayout
log4j.appender.D.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss}  [ %t:%r ] - [ %p ]  %m%n
 
### 输出ERROR 级别以上的日志到=E://logs/error.log ###
log4j.appender.E = org.apache.log4j.DailyRollingFileAppender
log4j.appender.E.File =E://logs/error.log 
log4j.appender.E.Append = true
log4j.appender.E.Threshold = ERROR 
log4j.appender.E.layout = org.apache.log4j.PatternLayout
log4j.appender.E.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss}  [ %t:%r ] - [ %p ]  %m%n

5，在配置文件下创建dao的配置文件
注意：在resources下创建文件一层一层创建

<?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="dao.UserDao">
    <!--配置查询所有-->
    <select id="findAll" resultType="domain.User">
        select * from user;
    </select>
</mapper>

6，在test的Java文件目录下创建测试文件

/*
* Mybatis的入门案例
* */
public class MybatisTest {
    public static void main(String[] args) throws Exception {
        //1，读取配置文件
        InputStream in=Resources.getResourceAsStream("SqlMapConfig.xml");
        //2，创建SqlSessionFactory工厂
        SqlSessionFactoryBuilder builder=new SqlSessionFactoryBuilder();
        SqlSessionFactory factory=builder.build(in);
        //3，使用工厂生产SqlSession对象
        SqlSession session=factory.openSession();
        //4，使用SqlSession创建Dao接口的代理对象
        UserDao userDao=session.getMapper(UserDao.class);
        //5，使用代理对象执行方法
        List<User> users=userDao.findAll();
        for (User user : users) {
            System.out.println(user);
        }
        //6，释放资源
        session.close();
        in.close();
    }
}

基本就这样！