SSM框架是Spring、Spring MVC和MyBatis三个开源框架的整合，常用于构建数据源较简单的web项目。该框架是Java EE企业级开发的主流技术，也是每一个java开发者必备的技能。下面通过查询书籍列表的案例演示SSM整合的过程.

新建项目

创建文件目录

完整文件结构

引入依赖 

  <dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>4.0.1</version><scope>provided</scope></dependency><!--spring和springMVC环境依赖--><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>5.2.18.RELEASE</version></dependency><!--servlet依赖--><dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>3.1.0</version><scope>provided</scope></dependency><!--spring事务管理依赖--><dependency><groupId>org.springframework</groupId><artifactId>spring-jdbc</artifactId><version>5.2.18.RELEASE</version></dependency><!--mybatis依赖--><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.5.6</version></dependency><!--spring整合mybatis依赖--><dependency><groupId>org.mybatis</groupId><artifactId>mybatis-spring</artifactId><version>2.0.6</version></dependency><!--spring整合数据源依赖--><dependency><groupId>com.alibaba</groupId><artifactId>druid</artifactId><version>1.2.6</version></dependency><!--mysql数据库连接--><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>5.1.38</version></dependency><!--spring整合Junit依赖--><dependency><groupId>org.springframework</groupId><artifactId>spring-test</artifactId><version>5.2.18.RELEASE</version><scope>test</scope></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.12</version><scope>test</scope></dependency><!--lombok插件--><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.16.10</version></dependency><!--日志支持--><dependency><groupId>log4j</groupId><artifactId>log4j</artifactId><version>1.2.17</version></dependency><dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-databind</artifactId><version>2.9.0</version></dependency>

创建数据库表

jdbc属性文件

在resources目录下的props包中创建jdbc.properties文件

jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/mydb?useUnicode=true&characterEncoding=utf-8&useSSL=false
jdbc.username=root
jdbc.password=mysqlpass

创建配置类

jdbcConfig

import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;import javax.sql.DataSource;
@Configuration
//加载资源路径
@PropertySource("classpath:props/jdbc.properties")
public class JdbcConfig {@Value("${jdbc.driverClass}")private String driverClass;@Value("${jdbc.username}")private String username;@Value("${jdbc.password}")private String password;@Value("${jdbc.url}")private String url;/**配置Druid数据源*//**@Bean将返回的dataSource标识为被Spring管理的bean对象*/@Beanpublic DataSource dataSource(){DruidDataSource dataSource = new DruidDataSource();dataSource.setDriverClassName(driverClass);dataSource.setUsername(username);dataSource.setPassword(password);dataSource.setUrl(url);return dataSource;}
}

MyBatisConfig

import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.mapper.MapperScannerConfigurer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;import javax.sql.DataSource;
import java.io.IOException;@Configuration
@Import(JdbcConfig.class)
public class MyBatisConfig {@Beanpublic SqlSessionFactoryBean sqlSessionFactoryBean(DataSource dataSource) throws IOException {SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean();sessionFactoryBean.setDataSource(dataSource);//加载全局配置文件Resource configResource = new ClassPathResource("mybatis/mybatis-config.xml");sessionFactoryBean.setConfigLocation(configResource);//映射文件加载ResourcePatternResolver resourceResolver= new PathMatchingResourcePatternResolver();sessionFactoryBean.setMapperLocations(resourceResolver.getResources("classpath*:mybatis/mapper/*Mapper.xml"));return sessionFactoryBean;}@Beanpublic MapperScannerConfigurer mapperScannerConfigurer(){MapperScannerConfigurer scannerConfigurer = new MapperScannerConfigurer();//扫描mapper接口所在的包scannerConfigurer.setBasePackage("com.yaorange.ssm.mapper");return scannerConfigurer;}
}

SpringConfig

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;import javax.sql.DataSource;@Configuration
//扫描业务类实现类所在的包
@ComponentScan("com.yaorange.ssm.service.impl")
//加载MyBatisConfig和JdbcConfig配置类的字节码文件
@Import({MyBatisConfig.class, JdbcConfig.class})
//开启事务管理器
@EnableTransactionManagement
public class SpringConfig {@Bean/**配置事务管理器*/public PlatformTransactionManager transactionManager(DataSource dataSource){DataSourceTransactionManager transactionManager = new DataSourceTransactionManager();transactionManager.setDataSource(dataSource);return transactionManager;}
}

SpringMvcConfig

@Configuration
//扫描controller所在的包
@ComponentScan("com.yaorange.ssm.controller")
@EnableWebMvc
public class SpringMvcConfig {
}

ServletConfig配置类(用于加载Spring和SpringMVC配置类)

import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;public class ServletConfig extends AbstractAnnotationConfigDispatcherServletInitializer {@Override/**加载Spring配置,创建Spring容器*/protected Class<?>[] getRootConfigClasses() {return new Class[] {SpringConfig.class};}@Override/**加载SpringMVC配置,创建SpringMVC容器*/protected Class<?>[] getServletConfigClasses() {return new Class[] {SpringMvcConfig.class};}@Overrideprotected String[] getServletMappings() {//所有请求都交给SpringMVC处理return new String[] {"/"};}
}

功能模块开发

数据层开发

Book实体类

@Data
public class Books implements Serializable {/*** 书籍编号*/private Integer bId;/*** 书籍名称*/private String bName;/*** 作者*/private String authers;/*** 价格*/private BigDecimal price;/*** 出版年份*/private Object pubdate;/*** 备注*/private String note;/*** 数量*/private Integer num;}

mapper层BookMapper接口

public interface BooksMapper {  /**查询所有书籍*/List<Books> selectAll();
}

BookMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.yaorange.ssm.mapper.BooksMapper"><resultMap id="BaseResultMap" type="com.yaorange.ssm.entity.Books"><id property="bId" column="b_id" jdbcType="INTEGER"/><result property="bName" column="b_name" jdbcType="VARCHAR"/><result property="authers" column="authers" jdbcType="VARCHAR"/><result property="price" column="Price" jdbcType="DECIMAL"/><result property="pubdate" column="pubdate" jdbcType="OTHER"/><result property="note" column="note" jdbcType="VARCHAR"/><result property="num" column="num" jdbcType="INTEGER"/></resultMap><sql id="Base_Column_List">b_id,b_name,authers,Price,pubdate,note,num</sql><select id="selectAll" resultMap="BaseResultMap">SELECT<include refid="Base_Column_List"/>FROMbooks</select></mapper>

业务层开发

BookService接口

public interface BookService {List<Books> selectAll();
}

BookServiceImpl实现类

@Service
//开启事务管理
@Transactional(rollbackFor = Exception.class)
public class BookServiceImpl implements BookService {@Autowiredprivate BooksMapper booksMapper;@Overridepublic List<Books> selectAll() {return booksMapper.selectAll();}
}

控制层开发

@Controller
@ResponseBody
//根路径
@RequestMapping("/book")
public class BookController {@Autowiredprivate BookService bookService;@RequestMapping("/list")public Result selectAll(){List<Books> books = bookService.selectAll();return Result.ok(books);}
}

common包中的响应结果类和响应码常量

修改Tomcat中的访问路径

将多余的删除后点击apply

/**定义响应结果类*/
@Data
public class Result {//响应码private int code;//响应信息private String msg;//响应数据private Object data;public Result(int code, String msg) {this.code = code;this.msg = msg;}public Result(int code, String msg, Object data) {this.code = code;this.msg = msg;this.data = data;}public Result(String msg, Object data) {this.msg = msg;this.data = data;}public Result(Object data) {this.data = data;}public static Result success (){return new Result(HttpCode.SUCCESS_CODE,HttpMsg.SYS_OK_MSG);}public static Result ok(Object data){return new Result(data);}public static Result ok(String msg,Object data){return new Result(msg, data);}
}

public interface HttpCode {//成功响应码int SUCCESS_CODE=200;//失败响应码int ERROR_CODE=500;
}

public class HttpMsg {public static final String SYS_ERROR_MSG="操作失败";public static final String SYS_OK_MSG="操作成功";
}

postman接口测试结果