SpringMVC_SSM整合

一、回顾SpringMVC访问接口流程

1.容器加载分析

• 容器分析

  

• 手动注册WebApplicationContext

  public class ServletConfig extends AbstractDispatcherServletInitializer {
  
      @Override
      protected WebApplicationContext createServletApplicationContext() {
          //获取SpringMVC容器
          AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
          context.register(SpringMvcConfig.class);
          return context;
      }
  
      @Override
      protected String[] getServletMappings() {
          return new String[]{"/"};
      }
  
      @Override
      protected WebApplicationContext createRootApplicationContext() {
          return null;
      }
  }
  

2.容器加载过程分析

• tomcat 服务器启动的时候，加载ServletConfig类之后，做初始化web容器操作，相当于 web.xml

• 执行注册容器的方法,获取 SpringMVC容器 WebApplicationContext

  @Nullable
      protected WebApplicationContext createRootApplicationContext() {
          Class<?>[] configClasses = this.getRootConfigClasses();
          if (!ObjectUtils.isEmpty(configClasses)) {
              AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
              context.register(configClasses);
              return context;
          } else {
              return null;
          }
      }
  
      protected WebApplicationContext createServletApplicationContext() {
          AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
          Class<?>[] configClasses = this.getServletConfigClasses();
          if (!ObjectUtils.isEmpty(configClasses)) {
              context.register(configClasses);
          }
  
          return context;
      }
  

• 通过@ComponentScan(“cn.sycoder.controller”) 加载 Controller 下面的bean 进 WebApplicationContext

  @RestController
  public class TestController {
  
      @GetMapping("/test/{id}")
      public String test(@PathVariable Long id) {
          return "ok:" + id;
      }
  }
  

• 把使用了 RequestMapping 注解的方法的 value — 对应一个方法，建立起了一对一映射关系（可以想象hashmap）

  • /test/{id} ---- test 方法

3.请求接口过程

• 访问 http://localhost:8082/test/1
• 匹配 springmvc 的 / servletMapping 规则，交给 springmvc 处理
• 解析 /test/1路径找到对应的 test 方法
• 执行方法
• 因为使用 RestController ，所以返回方法的返回值作为响应体返回给浏览器

4.SSM整合会出现bean界定不清楚问题

• SpringMVC 需要加载哪些bean?
  • controller 层（表现层即可）
• Spring 加载哪些bean?
  • service
  • dao

4.1如何处理

• 将spring配置注入到 web 容器中

  @Configuration
  @ComponentScan(value={"cn.sycoder.service","cn.sycoder.dao"})
  public class SpringConfig {
  }
  
  

  public class ServletConfig  extends AbstractAnnotationConfigDispatcherServletInitializer {
      @Override
      protected Class<?>[] getRootConfigClasses() {
          return new Class[]{SpringConfig.class};
      }
  
      @Override
      protected Class<?>[] getServletConfigClasses() {
          return new Class[]{SpringMvcConfig.class};
      }
  
      @Override
      protected String[] getServletMappings() {
          return new String[]{"/"};
      }
  }
  

4.2验证两个容器的bean相互不干扰

• 验证代码

  @Test
  public void test(){
      AnnotationConfigApplicationContext applicationContext =
              new AnnotationConfigApplicationContext(SpringConfig.class);
      ITestService bean = applicationContext.getBean(ITestService.class);
      bean.get(1L);
  
      TestController bean1 = applicationContext.getBean(TestController.class);
      System.out.println(bean1.test(1L));
  }
  

二、SSM整合

1.SSM整合流程分析

• 概述SSM：Spring SpringMVC Mybatis

1.1创建工程

• 导入依赖

  • ssm 所需要的依赖包

• 配置 web 项目入口配置替换 web.xml（AbstractAnnotationConfigDispatcherServletInitializer）

  • 配置 Spring 配置类交给 web 容器管理

    @Override
        protected Class<?>[] getRootConfigClasses() {
            return new Class[]{SpringConfig.class};
        }
    

  • 配置 SpringMVC 配置类交给 web 容器管理

    @Override
        protected Class<?>[] getServletConfigClasses() {
            return new Class[]{SpringMvcConfig.class};
        }
    

  • 配置请求拦截规则,交给 springmvc 处理

    @Override
        protected String[] getServletMappings() {
            return new String[]{"/"};
        }
    

1.2配置 Spring

• SpringConfig
  • @Configuration 标记Spring配置类，替换Spring-config-xml
  • @ComponetScan 扫描需要被Spring 管理的bean
  • @EnableTransactionManagment 启动管理事务支持
  • @PropertySource 引入db.properties 配置文件
• 配置 JdbcConfig 配置类
  • 使用德鲁伊 DataSource 数据源
  • 构建平台事务管理器 DataSourceTransactionManager
• 配置 MyBatis 配置类
  • 构建 SqlSessionFactoryBean
  • 指定 MapperScanner 设置 mapper 包扫描寻找 mapper.xml 文件

1.3配置 SpringMVC

• 配置SpringMvcConfig
  • @Configuration
  • @ComponentScan 只扫描 Controller
  • 开启SpringMVC 注解支持 @EnableWebMvc

1.4开发业务

• 使用注解
  • 注入bean 注解
    • @Autowired
  • @RestController
    • @GetMapping
      • @RequestParam
    • @PostMapping
      • @RequestBody
    • @DeleteMapping
      • @PathVariable
    • @PutMapping
  • @Service
    • @Transactional
  • junit
    • @RunWith
    • @ContextConfiguration
    • @Test

2.SSM整合

2.1导入依赖

• 依赖

  <dependencies>
      <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>5.2.17.RELEASE</version>
      </dependency>
  
      <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.2.17.RELEASE</version>
      </dependency>
  
      <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>5.2.17.RELEASE</version>
      </dependency>
  
      <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.6</version>
      </dependency>
  
      <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis-spring</artifactId>
        <version>1.3.0</version>
      </dependency>
  
      <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.29</version>
      </dependency>
  
      <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>1.1.16</version>
      </dependency>
  
      <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
      </dependency>
  
      <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
        <scope>provided</scope>
      </dependency>
  
      <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.9.0</version>
      </dependency>
    </dependencies>
  

2.2创建各目录结构

• 目录如下

  

2.3创建SpringConfig

• SpringConfig(在整合项目的时候不能扫描mvc的类，否则会出现创建容器失败)

  @Configuration
  @ComponentScan(value = {"cn.sycoder.service","cn.sycoder.dao"})
  @EnableTransactionManagement
  @PropertySource("classpath:db.properties")
  @Import({DbConfig.class,MybatisConfig.class})
  public class SpringConfig {
  }
  

2.4创建DbConfig配置类

• 创建数据库配置文件

  jdbc.url=jdbc:mysql://localhost:3306/ssm
  jdbc.driver=com.mysql.cj.jdbc.Driver
  jdbc.username=root
  jdbc.password=123456
  

• 创建DbConfig

  public class DbConfig {
      
      @Value("${jdbc.url}")
      private String url;
      @Value("${jdbc.driver}")
      private String driver;
      @Value("${jdbc.username}")
      private String username;
      @Value("${jdbc.password}")
      private String password;
  
      /**
       * 配置德鲁伊连接池
       * @return
       */
      @Bean
      public DataSource dataSource(){
          DruidDataSource source = new DruidDataSource();
          source.setUrl(url);
          source.setDriverClassName(driver);
          source.setPassword(password);
          source.setUsername(username);
          return source;
      }
      
      @Bean
      public PlatformTransactionManager transactionManager(DataSource dataSource){
          DataSourceTransactionManager manager = new DataSourceTransactionManager();
          manager.setDataSource(dataSource);
          return manager;
      }
      
  }
  

2.5创建MybatisConfig配置类

• MyBatisConfig

  public class MybatisConfig {
      
      @Bean
      public SqlSessionFactoryBean sessionFactoryBean(DataSource dataSource){
          SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
          bean.setDataSource(dataSource);
          bean.setTypeAliasesPackage("cn.sycoder.domain");
          return bean;
      }
      
      @Bean
      public MapperScannerConfigurer mapperScannerConfigurer(){
          MapperScannerConfigurer configurer = new MapperScannerConfigurer();
          configurer.setBasePackage("cn.sycoder.dao");
          return configurer;
      }
  }
  

2.6创建SpringMVC配置类

• SpringMvcConfig

  @Configuration
  @ComponentScan("cn.sycoder.controller")
  @EnableWebMvc
  public class SpringMvcConfig {
  }
  

2.7创建Web项目入口配置类

• ServletConfig

  public class ServletConfig extends AbstractAnnotationConfigDispatcherServletInitializer {
      @Override
      protected Class<?>[] getRootConfigClasses() {
          return new Class[]{SpringConfig.class};//配置Spring交给Web 管理
      }
  
      @Override
      protected Class<?>[] getServletConfigClasses() {
          return new Class[]{SpringMvcConfig.class};
      }
  
      @Override
      protected String[] getServletMappings() {
          return new String[]{"/"};
      }
  }
  

3.功能开发

3.1创建数据库及表

• 创建 ssm 数据库

• 创建 item 表

  create table item
  (
  	id bigint auto_increment,
  	type varchar(64) null,
  	name varchar(64) null,
  	remark text null,
  	constraint item_pk
  		primary key (id)
  );
  
  

3.2编写模型类

• 添加 lombok 依赖

  <dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.18.22</version>
  </dependency>
  

• 模型类

  @Data
  public class Item {
      private Long id;
      private String name;
      private String type;
      private String remark;
  }
  

3.3编写Mapper接口

• Mapper 接口

  @Repository
  public interface ItemMapper {
      @Insert("insert into item(name,type,remark) value(#{name},#{type},#{remark})")
      public int save(Item item);
      @Delete("delete from item where id = #{id}")
      public int delete(Long id);
      @Update("update item set name = #{name},type = #{type},remark=#{remark} where id=#{id}")
      public int update(Item item);
      @Select("select * from item where id = #{id}")
      public Item getById(Long id);
      @Select("select * from item")
      public List<Item> list();
  
  }
  

3.4编写Service接口和实现类

• Service 接口

  public interface IItemService {
      /**
       * 添加闲置物品方法
       * @param item
       * @return
       */
      public boolean save(Item item);
  
      /**
       * 删除闲置物品
       * @param id
       * @return
       */
      public boolean delete(Long id);
  
      /**
       * 更新闲置物品
       * @param item
       * @return
       */
      public boolean update(Item item);
  
      /**
       * 查询闲置物品通过id
       * @param id
       * @return
       */
      public Item getById(Long id);
  
      /**
       * 查询所有闲置商品
       * @return
       */
      public List<Item> lists();
  }
  

• 定义接口实现类

  @Service
  public class ItemServiceImpl implements IItemService {
      
      @Autowired
      ItemMapper mapper;
      
      @Override
      @Transactional
      public boolean save(Item item) {
          return mapper.save(item) > 0;
      }
  
      @Override
      @Transactional
      public boolean delete(Long id) {
          return mapper.delete(id) >0;
      }
  
      @Override
      @Transactional
      public boolean update(Item item) {
          return mapper.update(item) >0;
      }
  
      @Override
      public Item getById(Long id) {
          return mapper.getById(id);
      }
  
      @Override
      public List<Item> lists() {
          return mapper.list();
      }
  }
  

3.5编写Contorller类

• Controller

  @RestController
  @RequestMapping("/item")
  public class ItemController {
  
      @Autowired
      IItemService service;
  
      @PostMapping
      public boolean save(@RequestBody Item item){
          return service.save(item);
      }
  
      @PutMapping
      public boolean update(@RequestBody Item item){
          return service.update(item);
      }
  
      @DeleteMapping("/{id}")
      public boolean delete(@PathVariable Long id){
          return service.delete(id);
      }
  
      @GetMapping("/{id}")
      public Item getById(@PathVariable Long id){
          return service.getById(id);
      }
  
      @GetMapping
      public List<Item> list(){
          return service.lists();
      }
  }
  

4.验证 ssm 整合结果

• 启动项目并且解决问题

  

• 修改Spring配置类

  @Configuration
  @ComponentScan(value = {"cn.sycoder.service","cn.sycoder.dao"})
  @EnableTransactionManagement
  @PropertySource("classpath:db.properties")
  @Import({DbConfig.class,MybatisConfig.class})
  public class SpringConfig {
  }
  

4.1添加item 数据

• 准备 item 数据

  {"name":"键盘","type":"电脑外设","remark":"9成新，半价卖"}
  

  {"name":"笔记本","type":"电脑","remark":"9成新，8折出售"}
  

  {"name":"鞋子","type":"收藏鞋","remark":"科比签名的，独一无二"}
  

• 添加数据

  

4.2修改数据

• 准备数据

  {"id":4,"name":"二手鞋子","type":"废鞋","remark":"破鞋子"}
  

• 修改操作

  

4.3查询单个数据

• 查询id=4的物品

  

4.4删除单个数据

• 删除id=4的物品

  

4.5查询全部数据操作

• 查询全部

  

5.整合单元测试

• 目录结构

  

• 新建测试类

  @RunWith(SpringJUnit4ClassRunner.class)
  @ContextConfiguration(classes = SpringConfig.class)
  public class ItemTest {
  
      @Autowired
      IItemService service;
  
  
      @Test
      public void save(){
          Item item = new Item();
          item.setName("单元测试");
          item.setRemark("单元测试");
          item.setType("单元测试");
          boolean save = service.save(item);
          System.out.println(save);
      }
  
      @Test
      public void update(){
          Item item = new Item();
          item.setId(5L);
          item.setName("单元测试");
          item.setRemark("单元测试");
          item.setType("单元测试");
          boolean save = service.update(item);
          System.out.println(save);
      }
  
      @Test
      public void getById(){
          Item byId = service.getById(5L);
          System.out.println(byId);
      }
  
      @Test
      public void list(){
          List<Item> lists = service.lists();
          System.out.println(lists);
      }
  }
  

三、项目实战中细节问题

1.导入前端资源

1.1静态资源拦截处理

• 设置访问 index 访问主页

  @Controller
  public class IndexController {
      @RequestMapping("/index")
      public String index(){
          System.out.println("----------------");
          return "/pages/items.html";
      }
  
  }
  

• 出现静态资源被拦截问题

  @Configuration
  public class StaticSupport extends WebMvcConfigurationSupport {
  
      @Override
      protected void addResourceHandlers(ResourceHandlerRegistry registry) {
          registry.addResourceHandler("/pages/**").addResourceLocations("/pages/");
          registry.addResourceHandler("/js/**").addResourceLocations("/js/");
          registry.addResourceHandler("/css/**").addResourceLocations("/css/");
          registry.addResourceHandler("/plugins/**").addResourceLocations("/plugins/");
  
      }
  }
  

• 将 staticSupport 交给 SpringMvc 管理

  @Configuration
  @ComponentScan(value = {"cn.sycoder.controller","cn.sycoder.config"})
  @EnableWebMvc
  public class SpringMvcConfig {
  }
  

1.2项目实现

• 保存方法

  handleAdd () {
      console.log("========")
      axios.post("/item",this.formData).then((res)=>{
          //todo
      })
  },
  

• 列表查询

  getAll() {
      axios.get("/item",).then((res)=>{
          this.dataList = res.data;
      })
  },
  

• 删除操作

  handleDelete(row) {
      axios.delete("/item/"+row.id).then((res)=>{
          //todo
      })
  }