1. mybatis 的入门实例

mybatis 的入门实例

1.创建一个普通的Java项目

1.加入jar包（所有mybatis 和mysql）

2.加入配置文件

src 目录下

(1) db.properties

mysql.user = root

mysql.password = root

mysql.driver = com.mysql.jdbc.Driver

mysql.url = jdbc:mysql:///blog

(2)log4j.properties

### direct log messages to stdout ###

log4j.appender.stdout=org.apache.log4j.ConsoleAppender

log4j.appender.stdout.Target=System.err

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

log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

### direct messages to file mylog.log ###

log4j.appender.file=org.apache.log4j.FileAppender

log4j.appender.file.File=c\:mylog.log

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

log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

### set log levels - for more verbose logging change 'info' to 'debug' ###

log4j.rootLogger=debug, stdout

(3)mybatis-config.xml 核心配置文件

<?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>

<!-- 引入数据库连接配置 -->

<properties resource="db.properties"></properties>

<!-- 定义数据源 -->

<environments default="development">

<environment id="development">

<transactionManager type="JDBC"></transactionManager>

<dataSource type="POOLED">

<property name="user" value="${mysql.user}"/>

<property name="password" value="${mysql.password}"/>

<property name="driver" value="${mysql.driver}"/>

<property name="url" value="${mysql.url}"/>

</dataSource>

</environment>

</environments>

 

<!-- mapper 定义映射文件 -->

<mappers>

<!-- <mapper resource="com/xms/mybatis/mapper/BlogMapper.xml"/>-->

<package name="com.xms.mybatis.mapper"/>

</mappers>

</configuration>

(4)mapper.xml

<?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">

<!-- 该文件编写mybatis中的mapper接口里面的方法提供对应的sql语句 -->

<mapper namespace="com.xms.mybatis.mapper.BlogMapper">

<select id=""></select>

<insert id=""></insert>

<delete id=""></delete>

<update id=""></update>

</mapper>

3.编写接口

package com.xms.mybatis.mapper;

import com.xms.mybatis.pojo.Blog;

public interface BlogMapper {

 

Blog selectBlog(Integer id);

}

4.创建工具类

package com.xms.mybatis.utils;

import java.io.IOException;

import java.io.InputStream;

import org.apache.ibatis.io.Resources;

import org.apache.ibatis.session.SqlSession;

import org.apache.ibatis.session.SqlSessionFactory;

import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class MybatisUtil {

 

private MybatisUtil(){}

private static SqlSessionFactory sqlsessionFactory = null;

 

static{

 

try {

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

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

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

public static SqlSession getSqlSession(){

 

return sqlsessionFactory.openSession();

}

}

5.创建pojo

package com.xms.mybatis.pojo;

 

public class Blog {

 

private Integer id;

private String title;

@Override

public String toString() {

return "Blog [id=" + id + ", title=" + title + ", authorId=" + authorId + ", state=" + state + ", featured="

+ featured + ", ]";

}

public Integer getId() {

return id;

}

public void setId(Integer id) {

this.id = id;

}

public String getTitle() {

return title;

}

public void setTitle(String title) {

this.title = title;

}

public Integer getAuthorId() {

return authorId;

}

public void setAuthorId(Integer authorId) {

this.authorId = authorId;

}

public String getState() {

return state;

}

public void setState(String state) {

this.state = state;

}

public Boolean getFeatured() {

return featured;

}

public void setFeatured(Boolean featured) {

this.featured = featured;

}

public String getStyle() {

return style;

}

public void setStyle(String style) {

this.style = style;

}

private Integer authorId;

private String state;

private Boolean featured;

private String style;

 

}

6.测试类Test

package com.xms.mybatis.mapper;

 

import org.apache.ibatis.session.SqlSession;

import org.junit.Test;

 

import com.xms.mybatis.pojo.Blog;

import com.xms.mybatis.utils.MybatisUtil;

 

public class BlogMaperTest {

 

@Test

public void testSelectBlog(){

 

SqlSession session = MybatisUtil.getSqlSession();

BlogMapper blogMapper = session.getMapper(BlogMapper.class);

Blog blog = blogMapper.selectBlog(1);

session.close();

System.out.println("<<<<<------------>>>>>:"+blog);

 

}

 

}

 

mybatis 简单的入门 哈哈哈

希望对入门的道友有帮助

欢迎各位道友吐槽