基于mybatis框架的maven访问MySQL数据库
时间: 2024-09-20 20:12:56 浏览: 33
基于MyBatis框架并利用Maven构建项目时,访问MySQL数据库通常包含以下几个步骤:
1. **添加依赖**:
在`pom.xml`文件中添加MyBatis及其数据源(如Spring Boot集成的是JPA的HikariCP)的相关依赖:
```xml
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- 如果使用Spring Boot,还需添加Spring Data JPA或Spring JDBC相关依赖 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
</dependencies>
```
2. **配置数据源**:
Spring Boot项目中,可以在application.properties或application.yml文件里设置数据库连接信息:
```properties
spring.datasource.url=jdbc:mysql://localhost:3306/mydb?useSSL=false
spring.datasource.username=myuser
spring.datasource.password=mypassword
spring.jpa.hibernate.ddl-auto=update
```
3. **创建Mapper接口**:
在`src/main/java`目录下,创建Mapper接口,例如UserMapper.java,它会映射到数据库表操作:
```java
public interface UserMapper {
List<User> getAllUsers();
User getUserById(@Param("id") int id);
}
```
4. **编写XML映射文件**:
创建mapper文件夹,如`src/main/resources/mapper/UserMapper.xml`,这里定义SQL语句和其对应的接口方法:
```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">
<mapper namespace="com.example.mapper.UserMapper">
<select id="getAllUsers" resultType="com.example.entity.User">
SELECT * FROM users;
</select>
<select id="getUserById" parameterType="int" resultType="com.example.entity.User">
SELECT * FROM users WHERE id = #{id};
</select>
</mapper>
```
5. **注入和使用Mapper**:
在业务层(Service、Controller等)中通过SqlSessionFactory获取Mapper实例并进行数据库操作。