下面提供一个完整的 MyBatis 基础使用案例,包含从项目构建到单元测试的全部代码和配置。
一、项目结构
mybatis-demo ├── pom.xml ├── src │ └── main │ ├── java │ │ └── com │ │ └── example │ │ ├── entity │ │ │ └── User.java │ │ ├── mapper │ │ │ └── UserMapper.java │ │ └── MyBatisUtil.java │ └── resources │ ├── mybatis-config.xml │ ├── log4j.properties │ └── mapper │ └── UserMapper.xml └── test └── java └── com └── example └── UserMapperTest.java二、Maven 依赖(pom.xml)
<?xml version="1.0" encoding="UTF-8"?><projectxmlns="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.example</groupId><artifactId>mybatis-demo</artifactId><version>1.0-SNAPSHOT</version><properties><maven.compiler.source>11</maven.compiler.source><maven.compiler.target>11</maven.compiler.target><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding></properties><dependencies><!-- MyBatis --><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.5.13</version></dependency><!-- H2 内存数据库(也可换成 MySQL) --><dependency><groupId>com.h2database</groupId><artifactId>h2</artifactId><version>2.1.214</version></dependency><!-- Log4j 日志 --><dependency><groupId>log4j</groupId><artifactId>log4j</artifactId><version>1.2.17</version></dependency><!-- 单元测试 --><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.13.2</version><scope>test</scope></dependency></dependencies><build><resources><resource><directory>src/main/resources</directory><filtering>false</filtering></resource></resources></build></project>三、日志配置(log4j.properties)
# 根日志级别,输出到控制台 log4j.rootLogger=DEBUG, console # 控制台输出配置 log4j.appender.console=org.apache.log4j.ConsoleAppender log4j.appender.console.Target=System.out log4j.appender.console.layout=org.apache.log4j.PatternLayout log4j.appender.console.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n # 显示 MyBatis SQL 语句 log4j.logger.com.example.mapper=DEBUG四、MyBatis 全局配置(mybatis-config.xml)
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