首页 > 其他分享 >【SSM框架探索】第二篇——SSM整合与表现层数据封装优化

【SSM框架探索】第二篇——SSM整合与表现层数据封装优化

时间:2024-10-15 23:18:08浏览次数:3  
标签:封装 id SSM book Result Integer return 第二篇 public

目录

1 SSM整合配置

问题导入

1.1 SSM整合流程

1.2.2 Spring整合Mybatis

1.2.3 Spring整合SpringMVC

2.1 数据层开发(BookDao)

2.2 业务层开发(BookService/BookServiceImpl)

2.3 表现层开发(BookController)

3.1 Spring整合Junit测试业务层方法

3.2 postman测试表现层接口

问题导入

1 表现层响应数据的问题

2 定义Result类封装响应结果

2.1 Result类封装响应结果

2.2 Code类封装响应码

3 表现层数据封装返回Result对象


一、SSM整合【重点】

1 SSM整合配置

问题导入

请描述“SSM整合流程”中各个配置类的作用?

1.1 SSM整合流程
  1.  创建工程
  2.  SSM整合
  • Spring
    • SpringConfig
  • MyBatis
    • MybatisConfig
    • JdbcConfig
    • jdbc.properties
  • SpringMVC
    • ServletConfig
    • SpringMvcConfig

1.2.1 创建工程,添加依赖和插件

<dependencies>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>5.2.10.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.2.10.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>5.2.10.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>5.1.47</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>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.tomcat.maven</groupId>
            <artifactId>tomcat7-maven-plugin</artifactId>
            <version>2.1</version>
            <configuration>
                <port>80</port>
                <path>/</path>
            </configuration>
        </plugin>
    </plugins>
</build>
1.2.2 Spring整合Mybatis
  • 创建数据库和表 -- 创建ssm_db数据库
 CREATE DATABASE IF NOT EXISTS ssm_db CHARACTER SET utf8;  -- 使用ssm_db数据库
  USE ssm_db;  -- 创建tbl_book表
  CREATE TABLE tbl_book(
    id INT PRIMARY KEY AUTO_INCREMENT, -- 图书编号
    TYPE VARCHAR(100), -- 图书类型
    NAME VARCHAR(100), -- 图书名称
    description VARCHAR(100) -- 图书描述
  );
  -- 添加初始化数据
  INSERT INTO tbl_book VALUES(NULL,'计算机理论','Spring实战 第5版','Spring入门经典教材,深入理解Spring原理技术内幕');
  INSERT INTO tbl_book VALUES(NULL,'计算机理论','Spring 5核心原理与30个类手写实战','十年沉淀之作,手写Spring精华思想');
  INSERT INTO tbl_book VALUES(NULL,'计算机理论','Spring 5设计模式','深入Spring源码剖析,Spring源码蕴含的10大设计模式');
  INSERT INTO tbl_book VALUES(NULL,'市场营销','直播就该这么做:主播高效沟通实战指南','李子柒、李佳琦、薇娅成长为网红的秘密都在书中');
  INSERT INTO tbl_book VALUES(NULL,'市场营销','直播销讲实战一本通','和秋叶一起学系列网络营销书籍');
  INSERT INTO tbl_book VALUES(NULL,'市场营销','直播带货:淘宝、天猫直播从新手到高手','一本教你如何玩转直播的书,10堂课轻松实现带货月入3W+');
jdbc.properties属性文件  jdbc.driver=com.mysql.jdbc.Driver
  jdbc.url=jdbc:mysql://localhost:3306/ssm_db
  jdbc.username=root
  jdbc.password=root
  • JdbcConfig配置类
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;
    //配置连接池
    @Bean
    public DataSource dataSource(){
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(driver);
        dataSource.setUrl(url);
        dataSource.setUsername(username);
        dataSource.setPassword(password);
        return dataSource;
    }
    //Spring事务管理需要的平台事务管理器对象
    @Bean
    public PlatformTransactionManager transactionManager(DataSource dataSource){
        DataSourceTransactionManager ds = new DataSourceTransactionManager();
        ds.setDataSource(dataSource);
        return ds;
    }
}
  • MybatisConfig配置类
● public class MyBatisConfig {
  @Bean
  public SqlSessionFactoryBean sqlSessionFactory(DataSource dataSource){
      SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
      factoryBean.setDataSource(dataSource);
      factoryBean.setTypeAliasesPackage("com.itheima.domain");
      return factoryBean;
  }

  @Bean
  public MapperScannerConfigurer mapperScannerConfigurer(){
      MapperScannerConfigurer msc = new MapperScannerConfigurer();
      msc.setBasePackage("com.itheima.dao");
      return msc;
  }
  }
  • SpringConfig配置类
  @Configuration
  @ComponentScan({"com.itheima.service"})
  @PropertySource("classpath:jdbc.properties")
  @Import({JdbcConfig.class,MyBatisConfig.class})
  @EnableTransactionManagement //开启Spring事务管理
  public class SpringConfig {
  }
1.2.3 Spring整合SpringMVC
  • SpringMvcConfig配置类
@Configuration
  @ComponentScan("com.itheima.controller")
  @EnableWebMvc
  public class SpringMvcConfig {
  }
  • ServletConfig配置类,加载SpringMvcConfig和SpringConfig配置类
public class ServletConfig extends AbstractAnnotationConfigDispatcherServletInitializer {
    protected Class<?>[] getRootConfigClasses() {
        return new Class[]{SpringConfig.class};
    }

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

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

2 功能模块开发

2.1 数据层开发(BookDao)
  • Book实体类
public class Book {
  private Integer id;
  private String type;
  private String name;
  private String description;
  //同学们自己添加getter、setter、toString()方法
  }
  • BookDao接口
public interface BookDao {

  //@Insert("insert into tbl_book values(null,#{type},#{name},#{description})")
  @Insert("insert into tbl_book (type,name,description) values(#{type},#{name},#{description})")
  public int save(Book book);  //返回值表示影响的行数

  @Update("update tbl_book set type = #{type}, name = #{name}, description = #{description} where id = #{id}")
  public int update(Book book);

  @Delete("delete from tbl_book where id = #{id}")
  public int delete(Integer id);

  @Select("select * from tbl_book where id = #{id}")
  public Book getById(Integer id);

  @Select("select * from tbl_book")
  public List<Book> getAll();
}
2.2 业务层开发(BookService/BookServiceImpl)
  • BookService接口
@Transactional //表示所有方法进行事务管理
public interface BookService {

    /**
     * 保存
     * @param book
     * @return
     */
    public boolean save(Book book);

    /**
     * 修改
     * @param book
     * @return
     */
    public boolean update(Book book);

    /**
     * 按id删除
     * @param id
     * @return
     */
    public boolean delete(Integer id);

    /**
     * 按id查询
     * @param id
     * @return
     */
    public Book getById(Integer id);

    /**
     * 查询全部
     * @return
     */
    public List<Book> getAll();
}
  • BookServiceImpl实现类
@Service
public class BookServiceImpl implements BookService {
    @Autowired
    private BookDao bookDao;

    public boolean save(Book book) {
        bookDao.save(book);
        return true;
    }

    public boolean update(Book book) {
        bookDao.update(book);
        return true;
    }

    public boolean delete(Integer id) {
        bookDao.delete(id);
        return true;
    }

    public Book getById(Integer id) {
        return bookDao.getById(id);
    }

    public List<Book> getAll() {
        return bookDao.getAll();
    }
}
2.3 表现层开发(BookController)
@RestController
@RequestMapping("/books")
public class BookController {

    @Autowired
    private BookService bookService;

    @PostMapping
    public boolean save(@RequestBody Book book) {
        return bookService.save(book);
    }

    @PutMapping
    public boolean update(@RequestBody Book book) {
        return bookService.update(book);
    }

    @DeleteMapping("/{id}")
    public boolean delete(@PathVariable Integer id) {
        return bookService.delete(id);
    }

    @GetMapping("/{id}")
    public Book getById(@PathVariable Integer id) {
        return bookService.getById(id);
    }

    @GetMapping
    public List<Book> getAll() {
        return bookService.getAll();
    }
}

3 接口测试

3.1 Spring整合Junit测试业务层方法
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = SpringConfig.class)
public class BookServiceTest {

    @Autowired
    private BookService bookService;

    @Test
    public void testGetById(){
        Book book = bookService.getById(1);
        System.out.println(book);
    }

    @Test
    public void testGetAll(){
        List<Book> all = bookService.getAll();
        System.out.println(all);
    }
}
3.2 postman测试表现层接口

该篇博客有讲过psotman的下载跟使用

  • 测试保存图书

这里就以保存图书为例

二、表现层数据封装【重点】

问题导入

目前我们表现层响应给客户端的数据有哪几种?

1 表现层响应数据的问题

问题:我们表现层增删改方法返回true或者false表示是否成功,getById()方法返回一个json对象,getAll()方法返回一个json对象数组,这里就出现了三种格式的响应结果,极其不利于前端解析。

解决:我们需要统一响应结果的格式

2 定义Result类封装响应结果

2.1 Result类封装响应结果
public class Result {
    //描述统一格式中的数据
    private Object data;
    //描述统一格式中的编码,用于区分操作,可以简化配置0或1表示成功失败
    private Integer code;
    //描述统一格式中的消息,可选属性
    private String msg;

    public Result() {
    }
    public Result(Integer code,Object data) {
        this.data = data;
        this.code = code;
    }
    public Result(Integer code, Object data, String msg) {
        this.data = data;
        this.code = code;
        this.msg = msg;
    }
     //自己添加getter、setter、toString()方法
}

注意事项:

Result类中的字段并不是固定的,可以根据需要自行增减

2.2 Code类封装响应码
//状态码
public class Code {
    public static final Integer SAVE_OK = 20011;
    public static final Integer DELETE_OK = 20021;
    public static final Integer UPDATE_OK = 20031;
    public static final Integer GET_OK = 20041;

    public static final Integer SAVE_ERR = 20010;
    public static final Integer DELETE_ERR = 20020;
    public static final Integer UPDATE_ERR = 20030;
    public static final Integer GET_ERR = 20040;
}

注意事项:

Code类的常量设计也不是固定的,可以根据需要自行增减,例如将查询再进行细分为GET_OK,GET_ALL_OK,GET_PAGE_OK

3 表现层数据封装返回Result对象

@RestController
@RequestMapping("/books")
public class BookController {

@Autowired
private BookService bookService;

@PostMapping
public Result save(@RequestBody Book book) {
boolean flag = bookService.save(book);
return new Result(flag ? Code.SAVE_OK:Code.SAVE_ERR,flag);
}

@PutMapping
public Result update(@RequestBody Book book) {
boolean flag = bookService.update(book);
return new Result(flag ? Code.UPDATE_OK:Code.UPDATE_ERR,flag);
}

@DeleteMapping("/{id}")
public Result delete(@PathVariable Integer id) {
boolean flag = bookService.delete(id);
return new Result(flag ? Code.DELETE_OK:Code.DELETE_ERR,flag);
}

@GetMapping("/{id}")
public Result getById(@PathVariable Integer id) {
Book book = bookService.getById(id);
Integer code = book != null ? Code.GET_OK : Code.GET_ERR;
String msg = book != null ? "" : "数据查询失败,请重试!";
return new Result(code,book,msg);
}

@GetMapping
public Result getAll() {
List<Book> bookList = bookService.getAll();
Integer code = bookList != null ? Code.GET_OK : Code.GET_ERR;
String msg = bookList != null ? "" : "数据查询失败,请重试!";
return new Result(code,bookList,msg);
}
}

标签:封装,id,SSM,book,Result,Integer,return,第二篇,public
From: https://blog.csdn.net/2301_80237574/article/details/142963409

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