SSM注解方式搭建

安装相关 maven 依赖

<dependencies>
    <!--  Spring MVC  -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>6.2.1</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>6.1.14</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>6.1.14</version>
        <scope>test</scope>
    </dependency>
    <!-- 引入 mybatis 依赖库-->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis-spring</artifactId>
        <version>3.0.4</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.16</version>
    </dependency>
    <!-- jdbc 驱动库 -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.33</version>
    </dependency>
    <!-- 连接池 -->
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>1.2.23</version>
    </dependency>
    <!-- servlet依赖 -->
    <dependency>
        <groupId>jakarta.servlet</groupId>
        <artifactId>jakarta.servlet-api</artifactId>
        <version>6.1.0</version>
        <scope>provided</scope>
    </dependency>
    <!--  测试库  -->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.13.1</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.18.0</version>
    </dependency>
</dependencies>

安装的依赖中的 jakarta.servlet 当 tomcat 运行时会加载执行 ServletConfig 类，然后需要在 ServletConfig 类中加载其他配置。

package com.example.config;

import jakarta.servlet.Filter;
import org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;

// 当 Web 容器启动时，加载Spring、SpringMVC 配置
public class ServletConfig extends AbstractAnnotationConfigDispatcherServletInitializer {
    // 加载 Spring 配置
    protected Class<?>[] getRootConfigClasses() {
        return new Class[]{SpringConfig.class};
    }

    // 加载 SpringMVC 配置
    protected Class<?>[] getServletConfigClasses() {
        return new Class[]{SpringMvcConfig.class};
    }

    // 初始化根路径
    protected String[] getServletMappings() {
        return new String[]{"/"};
    }

    @Override
    protected Filter[] getServletFilters() {
        CharacterEncodingFilter filter = new CharacterEncodingFilter();
        filter.setEncoding("utf-8");
        return new Filter[]{filter};
    }
}

SpringConfig 类相关配置

package com.example.config;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.context.annotation.PropertySource;
import org.springframework.transaction.annotation.EnableTransactionManagement;

// Spring 配置
@Configuration
@ComponentScan({"com.example.service"})
// 加载 jdbc.properties 配置文件
@PropertySource("classpath:db.properties")
// 导入 JdbcConfig、MybatisConfig 配置
@Import({JdbcConfig.class,MybatisConfig.class})
//开启事务注解扫描
@EnableTransactionManagement
public class SpringConfig {

}

JdbcConfig 类配置

package com.example.config;

import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;

import javax.sql.DataSource;

public class JdbcConfig {
    @Value("${jdbc.driver}")
    private String driver;
    @Value("${jdbc.url}")
    private String url;
    @Value("${jdbc.username}")
    private String username;
    @Value("${jdbc.password}")
    private String password;

    /**
     * 配置数据源
     */
    @Bean
    public DataSource dataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(driver);
        dataSource.setUrl(url);
        dataSource.setUsername(username);
        dataSource.setPassword(password);
        return dataSource;
    }

    /**
     * 配置事务管理器
     */
    @Bean
    public PlatformTransactionManager transactionManager(DataSource dataSource) {
        DataSourceTransactionManager ds = new DataSourceTransactionManager();
        ds.setDataSource(dataSource);
        return ds;
    }
}

MybatisConfig 类相关配置

package com.example.config;

import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.mapper.MapperScannerConfigurer;
import org.springframework.context.annotation.Bean;

import javax.sql.DataSource;

public class MybatisConfig {
    /**
     * 注入 JDBC 的 数据源 类
     * 然后创建 SqlSessionFactoryBean 类返回
     */
    @Bean
    public SqlSessionFactoryBean sqlSessionFactory(DataSource dataSource) {
        SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
        factoryBean.setDataSource(dataSource);
        factoryBean.setTypeAliasesPackage("com.example.domain"); // 扫描的 domain 实体类
        return factoryBean;
    }

    @Bean
    public MapperScannerConfigurer mapperScannerConfigurer() {
        MapperScannerConfigurer msc = new MapperScannerConfigurer();
        msc.setBasePackage("com.example.dao"); // 扫描 mapper
        return msc;
    }
}

SpringMvcConfig 类配置

package com.example.config;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;

// SpringMVC 配置
@Configuration
@ComponentScan({"com.example.controller", "com.example.config" })
@EnableWebMvc
public class SpringMvcConfig {
}

db.properties 文件的相关配置

# jdbc config
jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/company
jdbc.username=root
jdbc.password=root123