mybatis实现CRUD操作和优化代码及调试（mysql数据库）

Posted 2020-10-07 鲲鹏展翅

继续（二）说

1.工程结构

2.新建db.properties文件（我的数据库没有设置密码）

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/mybatis
name=root
password=

3.log4j.jar加入工程并添加log4j.xml文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
	<appender name="STDOUT" class="org.apache.log4j.ConsoleAppender">
		<layout class="org.apache.log4j.PatternLayout">
			<param name="ConversionPattern" value="%-5p %d{MM-dd HH:mm:ss,SSS} %m  (%F:%L) \\n" />
		</layout>
	</appender>
	<logger name="java.sql">
		<level value="debug" />
	</logger>
	<logger name="org.apache.ibatis">
		<level value="debug" />
	</logger>
	<root>
		<level value="debug" />
		<appender-ref ref="STDOUT" />
	</root>
</log4j:configuration>

4.conf.xml添加了起别名，添加了db.propreties的配置

<?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>

<properties resource="db.properties"/>
	
	<!-- 配置实体类的别名 -->
	<typeAliases>
		<!-- <typeAlias type="com.atguigu.day03_mybaits.test2.User" alias="User"/> -->
		<package name="com.kpzc.bean"/>
	</typeAliases>
<!-- 
	development : 开发模式
	work : 工作模式
 -->
	<environments default="development">
		<environment id="development">
			<transactionManager type="JDBC" />
			<dataSource type="POOLED">
				<property name="driver" value="${driver}" />
				<property name="url" value="${url}" />
				<property name="username" value="${name}" />
				<property name="password" value="${password}" />
			</dataSource>
		</environment>
	</environments>
	
	<mappers>
	<!-- 写mapper所在的包的路径 -->
		<mapper resource="com/kpzc/test1/userMapper.xml"/>
		 <mapper resource="com/kpzc/test2/userMapper.xml"/>
		<!--<mapper class="com.atguigu.day03_mybaits.test3.UserMapper"/>
		<mapper resource="com/atguigu/day03_mybaits/test4/orderMapper.xml"/>
		<mapper resource="com/atguigu/day03_mybaits/test5/ClassMapper.xml"/>
		<mapper resource="com/atguigu/day03_mybaits/test6/ClassMapper.xml"/>
		<mapper resource="com/atguigu/day03_mybaits/test7/userMapper.xml"/>
		<mapper resource="com/atguigu/day03_mybaits/test8/userMapper.xml"/>
		<mapper resource="com/atguigu/day03_mybaits/test9/userMapper.xml"/> -->
	</mappers>
</configuration>

5.运行查询就有log输出