javaweb基础之引入maven+mybatis

69 阅读 0 评论 46 点赞

我是靠谱客的博主忐忑长颈鹿，最近开发中收集的这篇文章主要介绍javaweb基础之引入maven+mybatis，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

1、首先引入maven和创建Javaweb项目

可以通过Maven官网直接下载

两个中任意一个都可以，然后直接解压到磁盘里。

由于maven默认的下载远程仓库是国外的，下载比较慢，所以需要改成阿里云镜像。

<!--默认依赖jar包下载位置 -->  
<localRepository>F:Maven.m2repository</localRepository>

  <!-- 阿里云镜像 -->
<mirrors>
       <mirror>
            <id>nexus-aliyun</id>
            <mirrorOf>*,!jeecg,!jeecg-snapshots,!getui-nexus</mirrorOf>
            <name>Nexus aliyun</name>
            <url>http://maven.aliyun.com/nexus/content/groups/public</url>
        </mirror> 
 </mirrors>

然后在需要配置下idea

新版的idea可能不叫other setting直接就是Setting for New projects 都是一样的这种设置是以后创建新项目都会采用这种配置。

然后就是创建maven版的javaweb项目

2、在pom.xml文件中添加依赖

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>com.gzh</groupId>
  <artifactId>maven02</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>


  <dependencies>
    <!--mysql驱动依赖-->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>8.0.28</version>
    </dependency>
     <!--单元测试依赖-->
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.12</version>
    </dependency>
      <!--引入mybatis依赖-->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.4.6</version>
    </dependency>
     <!--引入日志依赖-->
    <dependency>
      <groupId>log4j</groupId>
      <artifactId>log4j</artifactId>
      <version>1.2.16</version>
    </dependency>

  </dependencies>
</project>

3、配置mybatis配置文件

采用两种方式

第一种 xml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>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.cj.jdbc"/>
                <property name="url" value="jdbc:mysql://localhost:3306/dbName?serverTimezone=Asia/Shanghai"/>
                <property name="username" value="root"/>
                <property name="password" value="root"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="mapper/userMapper.xml"/>
    </mappers>
</configuration>

第二种 xml+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>
    <properties resource="db.properties"/>
    <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="${username}"/>
                <property name="password" value="${password}"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <!--注册映射文件userMapper-->
        <mapper resource="mapper/userMapper.xml"/>
    </mappers>
</configuration>

db.properties

driver=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/test?serverTimezone=Asia/Shanghai
username=root
password=123456

目录结构

4、配置userMapper.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">
<!--namespace对映着java中的mapper接口-->
<mapper namespace="com.gzh.element.mapper.UserMapper">
<!--id对应着接口中的方法名  parameterType 参数类型 resultType 返回类型  -->
    <select id="getUser" parameterType="int" resultType="com.gzh.element.entity.User">
        select * from user where id = #{id}
    </select>

    <insert id="insert" parameterType="com.gzh.element.entity.User">
        insert into user(id,uname,upassword) values (null,#{uname},#{upassword})
    </insert>

    <select id="selectAll" resultType="com.gzh.element.entity.User">
        select *from user
    </select>
</mapper>

5、配置下log4j日志文件

一、xml文件配置

<?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>

二、properties文件配置

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

6、测试执行

Reader reader;
	SqlSessionFactory sql;
	SqlSession sqlSession;
//实例代码块 当对象创建实例时执行
	{
		try{
			reader = Resources.getResourceAsReader("conf.xml");
			sql = new SqlSessionFactoryBuilder().build(reader);
			sqlSession = sql.openSession(true);
		}catch (Exception e){
			e.printStackTrace();
		}
	}

	@Test
	public void test(){
		List<User> list = sqlSession.selectList("com.gzh.mapper.UserMapper.getAllUser");
		for(User i : list){
			System.out.println(i);
		}
	}

结果