- 
db.properties
<a name="Mybatis"></a>
## Mybatis
<a name="8b3dcf3d"></a>
### 1. 创建实体类
```java
package com.william.po;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Book {
    private int bookID;
    private String bookName;
    private int bookCounts;
    private String detail;
}

2. 创建Dao层Mapper接口和Mapper.xml文件

• Mapper.class

package com.william.dao;
import com.william.po.Book;
import java.util.List;
public interface BookMapper {
    //增加一个Book
    int addBook(Book book);
    //根据id删除一个Book
    int deleteBookById(int id);
    //更新Book
    int updateBook(Book book);
    //根据id查询,返回一个Book
    Book queryBookById(int id);
    //查询全部Book,返回list集合
    List<Book> queryAllBook();
}

• Mapper.xml

  <?xml version="1.0" encoding="UTF-8" ?>
  <!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
  <mapper namespace="com.william.dao.BookMapper">
    <!--增加一个Book-->
    <insert id="addBook" parameterType="Book">
      insert into ssmbuild.book(bookName,bookCounts,detail)
      values (#{bookName}, #{bookCounts}, #{detail})
   </insert>
    <!--根据id删除一个Book-->
    <delete id="deleteBookById" parameterType="int">
      delete from ssmbuild.book where bookID=#{bookID}
   </delete>
    <!--更新Book-->
    <update id="updateBook" parameterType="Book">
      update ssmbuild.book
      set bookName = #{bookName},bookCounts = #{bookCounts},detail = #{detail}
      where bookID = #{bookID}
   </update>
    <!--根据id查询,返回一个Book-->
    <select id="queryBookById" resultType="Book">
      select * from ssmbuild.book
      where bookID = #{bookID}
   </select>
    <!--查询全部Book-->
    <select id="queryAllBook" resultType="Book">
      SELECT * from ssmbuild.book
   </select>
  </mapper>

3. 创建Service层的接口和实现类，并在其中调用Dao层

• Service.class ```java package com.william.service;

import com.william.po.Book; import java.util.List;

public interface BookService { //增加一个Book int addBook(Book book); //根据id删除一个Book int deleteBookById(int id); //更新Book int updateBook(Book book); //根据id查询,返回一个Book Book queryBookById(int id); //查询全部Book,返回list集合 List queryAllBook(); }

- 
ServiceImpl.class
```java
package com.william.service;
import com.william.dao.BookMapper;
import com.william.po.Book;
import java.util.List;
public class BookServiceImpl implements BookService {
    // 持有Dao层
    public BookMapper bookMapper;
    // 方法均调用Dao层中同名方法
    @Override
    public int addBook(Book book) {
        return bookMapper.addBook(book);
    }
    @Override
    public int deleteBookById(int id) {
        return bookMapper.deleteBookById(id);
    }
    @Override
    public int updateBook(Book book) {
        return bookMapper.updateBook(book);
    }
    @Override
    public Book queryBookById(int id) {
        return bookMapper.queryBookById(id);
    }
    @Override
    public List<Book> queryAllBook() {
        return bookMapper.queryAllBook();
    }
    public void setBookMapper(BookMapper bookMapper) {
        this.bookMapper = bookMapper;
    }
}

Spring

• spring-dao.xml

  <?xml version="1.0" encoding="UTF-8"?>
  <beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
    <!--    1.关联数据库配置文件-->
    <context:property-placeholder location="classpath:jdbc.properties"/>
    <!-- 2.数据库连接池 -->
    <!--数据库连接池
        dbcp 半自动化操作 不能自动连接
        c3p0 自动化操作（自动的加载配置文件 并且设置到对象里面）
    -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <!-- 配置连接池属性 -->
        <property name="driverClass" value="${jdbc.driver}"/>
        <property name="jdbcUrl" value="${jdbc.url}"/>
        <property name="user" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
        <!-- c3p0连接池的私有属性 -->
        <property name="maxPoolSize" value="30"/>
        <property name="minPoolSize" value="10"/>
        <!-- 关闭连接后不自动commit -->
        <property name="autoCommitOnClose" value="false"/>
        <!-- 获取连接超时时间 -->
        <property name="checkoutTimeout" value="10000"/>
        <!-- 当获取连接失败重试次数 -->
        <property name="acquireRetryAttempts" value="2"/>
    </bean>
    <!-- 3.配置SqlSessionFactory对象 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <!-- 注入数据库连接池 -->
        <property name="dataSource" ref="dataSource"/>
        <!-- 配置MyBatis全局配置文件:mybatis-config.xml -->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
    </bean>
    <!-- 4.配置扫描Dao接口包，动态实现Dao接口注入到spring容器中 -->
    <!--解释 ：https://www.cnblogs.com/jpfss/p/7799806.html-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!-- 注入sqlSessionFactory -->
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <!-- 给出需要扫描Dao接口包 -->
        <property name="basePackage" value="com.william.dao"/>
    </bean>
  </beans>

重点！！！！

参考：https://blog.csdn.net/qq598535550/article/details/51703190?ops_request_misc=%7B%22request%5Fid%22%3A%22160359229319724842930227%22%2C%22scm%22%3A%2220140713.130102334..%22%7D&request_id=160359229319724842930227&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2top_click~default-4-51703190.pc_first_rank_v2_rank_v28&utm_term=ssm&spm=1018.2118.3001.4187

• spring-service.xml ```xml <?xml version=”1.0” encoding=”UTF-8”?>

<a name="SpringMVC"></a>
## SpringMVC
- 
web.xml
```xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    <!--DispatcherServlet-->
    <servlet>
        <servlet-name>DispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <!--一定要注意:我们这里加载的是总的配置文件，之前被这里坑了！-->
            <param-value>classpath:applicationContext.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>DispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
    <!--encodingFilter-->
    <filter>
        <filter-name>encodingFilter</filter-name>
        <filter-class>
            org.springframework.web.filter.CharacterEncodingFilter
        </filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>utf-8</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    <!--Session过期时间-->
    <session-config>
        <session-timeout>15</session-timeout>
    </session-config>
</web-app>

• spring-mvc.xml ```xml <?xml version=”1.0” encoding=”UTF-8”?>

<a name="dc53819c"></a>
## 配置文件的整合
<a name="bbce0330"></a>
### 1.使用IDEA
![](https://gitee.com/qinweilong/cloudimage/raw/master/img/image-20201025154842299.png#alt=image-20201025154842299)
<a name="3e2ce77f"></a>
### 2.applicationContext.xml中配置
```xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd">
   <import resource="spring-dao.xml"/>
   <import resource="spring-service.xml"/>
   <import resource="spring-mvc.xml"/>
</beans>

Controller层

• bookController.class ```java package com.william.controller;

import com.william.po.Book; import com.william.service.BookService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping;

import java.util.List;

@Controller @RequestMapping(“/book”) public class BookController {

// 查询
@Autowired
@Qualifier("BookServiceImpl")
private BookService bookService;
@RequestMapping("/allBook")
public String list(Model model) {
    List<Book> list = bookService.queryAllBook();
    model.addAttribute("list", list);
    return "allBook";
}
// 增加
@RequestMapping("/toAddBook")
public String toAddPaper() {
    return "addBook";
}
@RequestMapping("/addBook")
public String addPaper(Book book) {
    System.out.println(book);
    bookService.addBook(book);
    // 重定向
    return "redirect:/book/allBook";
}
// 修改
@RequestMapping("/toUpdateBook")
public String toUpdateBook(Model model, int id) {
    Book book = bookService.queryBookById(id);
    System.out.println(book);
    model.addAttribute("book", book);
    return "updateBook";
}
@RequestMapping("/updateBook")
public String updateBook(Model model, Book book) {
    System.out.println(book);
    bookService.updateBook(book);
    Book books = bookService.queryBookById(book.getBookID());
    model.addAttribute("books", book);
    return "redirect:/book/allBook";
}
// 删除
@RequestMapping("/del/{bookId}")
public String deleteBook(@PathVariable("bookId") int id) {
    bookService.deleteBookById(id);
    return "redirect:/book/allBook";
}

} ```

另外编写对应前端页面

• allBook.jsp
• addBook.jsp
• updateBook.jsp