Mybatis(1) 创建Mybatis HelloWorld

简介：

MyBatis 是一款优秀的持久层框架，它支持定制化 SQL、存储过程以及高级映射。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以使用简单的 XML 或注解来配置和映射原生信息，将接口和 Java 的 POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录。　　　　　　——百度百科

创建maven工程:

项目结构：

pom.xml文件：

 1 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 2   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 3   <modelVersion>4.0.0</modelVersion>
 4 
 5   <groupId>com.itdoc.mybatis</groupId>
 6   <artifactId>mybatis-01</artifactId>
 7   <version>1.0-SNAPSHOT</version>
 8   <packaging>jar</packaging>
 9 
10   <name>mybatis-01</name>
11   <url>http://maven.apache.org</url>
12 
13   <properties>
14     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
15   </properties>
16 
17   <dependencies>
18     <!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-core -->
19     <dependency>
20       <groupId>org.apache.logging.log4j</groupId>
21       <artifactId>log4j-core</artifactId>
22       <version>2.8.2</version>
23     </dependency>
24 
25     <!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
26     <dependency>
27       <groupId>org.mybatis</groupId>
28       <artifactId>mybatis</artifactId>
29       <version>3.4.1</version>
30     </dependency>
31 
32     <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
33     <dependency>
34       <groupId>mysql</groupId>
35       <artifactId>mysql-connector-java</artifactId>
36       <version>5.1.38</version>
37     </dependency>
38 
39     <!-- https://mvnrepository.com/artifact/junit/junit -->
40     <dependency>
41       <groupId>junit</groupId>
42       <artifactId>junit</artifactId>
43       <version>4.12</version>
44     </dependency>
45 
46   </dependencies>
47 </project>

pom.xml

全局配置文件(mybatis-config.xml)：此配置文件不是必须的。

 1 <?xml version="1.0" encoding="UTF-8" ?>
 2 <!DOCTYPE configuration
 3  PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
 4  "http://mybatis.org/dtd/mybatis-3-config.dtd">
 5 <configuration>
 6     <environments default="development">
 7         <environment id="development">
 8             <transactionManager type="JDBC" />
 9             <dataSource type="POOLED">
10                 <property name="driver" value="com.mysql.jdbc.Driver" />
11                 <property name="url" value="jdbc:mysql://localhost:3306/mybatis" />
12                 <property name="username" value="root" />
13                 <property name="password" value="root" />
14             </dataSource>
15         </environment>
16     </environments>
17     <!-- 将写好的sql映射文件（EmployeeMapper.xml）一定要注册到全局配置文件(mybatis-config.xml)中 -->
18     <mappers>
19         <mapper resource="mapper/EmployeeMapper.xml" />
20     </mappers>
21 </configuration>

mybatis-config.xml

Mybatis中配置中相应的对应关系：

github源码：https://github.com/wcd19901010/Mybatis/tree/master/mybatis-01