SSM 框架整合

1、环境

IDEA
MySQL 5.5.40
Tomcat 9
Maven 3.6

2、数据库环境

创建一个数据库表

CREATE DATABASE `ssmbuild`;

USE `ssmbuild`;

DROP TABLE IF EXISTS `books`;

CREATE TABLE `books` (
`bookID` INT(10) NOT NULL AUTO_INCREMENT COMMENT ‘书id‘,
`bookName` VARCHAR(100) NOT NULL COMMENT ‘书名‘,
`bookCounts` INT(11) NOT NULL COMMENT ‘数量‘,
`detail` VARCHAR(200) NOT NULL COMMENT ‘描述‘,
KEY `bookID` (`bookID`)
) ENGINE=INNODB DEFAULT CHARSET=utf8

INSERT  INTO `books`(`bookID`,`bookName`,`bookCounts`,`detail`)VALUES 
(1,‘Java‘,1,‘从入门到放弃‘),
(2,‘MySQL‘,10,‘从删库到跑路‘),
(3,‘Linux‘,5,‘从进门到进牢‘);

3、基本环境搭建

新建Maven项目，ssmbuild，添加web的支持（生成最新的 web.xml 文件）

导入相关的 pom 依赖 pom.xml

junit，数据库驱动，连接池，servlet，jsp，mybatis，mybatis-spring，spring，Lombok插件

<!--依赖：junit，数据库驱动，连接池，servlet，jsp，mybatis，mybatis-spring，spring-->
<dependencies>
    <!--Junit-->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
    </dependency>
    <!--数据库驱动-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.47</version>
    </dependency>
    <!-- 数据库连接池: c3p0、dbcp -->
    <dependency>
        <groupId>com.mchange</groupId>
        <artifactId>c3p0</artifactId>
        <version>0.9.5.2</version>
    </dependency>

    <!--Servlet - JSP -->
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>servlet-api</artifactId>
        <version>2.5</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet.jsp</groupId>
        <artifactId>jsp-api</artifactId>
        <version>2.2</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>

    <!--Mybatis-->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.2</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis-spring</artifactId>
        <version>2.0.2</version>
    </dependency>

    <!--Spring-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>5.1.9.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.1.9.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjweaver</artifactId>
        <version>1.8.13</version>
    </dependency>

    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.10</version>
        <scope>provided</scope>
    </dependency>
</dependencies>

Maven 资源过滤设置

<!--静态资源导出问题-->
<build>
    <resources>
        <resource>
            <directory>src/main/java</directory>
            <includes>
                <include>**/*.properties</include>
                <include>**/*.xml</include>
            </includes>
            <filtering>false</filtering>
        </resource>
        <resource>
            <directory>src/main/resources</directory>
            <includes>
                <include>**/*.properties</include>
                <include>**/*.xml</include>
            </includes>
            <filtering>false</filtering>
        </resource>
    </resources>
</build>

建立基本结构和配置框架

com.song.pojo
com.song.dao
com.song.service
com.song.controller
mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
          PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
          "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>

</configuration>

applicationContext.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">

</beans>

4、Mybatis 层

数据库配置文件 database.properties

jdbc.driver=com.mysql.jdbc.Driver
# 如果使用的是 MySQL8.0+，增加一个时区的配置 serverTimezone=Asia/Shanghai
jdbc.url=jdbc:mysql://localhost:3306/ssmbuild?useSSL=true&useUnicode=true&characterEncoding=utf8
jdbc.username=root
jdbc.password=root

IDEA关联数据库

编写 MyBatis 的核心配置文件 mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>

    <!-- 配置数据源交给 Spring 做-->

    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>

    <typeAliases>
        <package name="com.song.pojo"/>
    </typeAliases>

    <mappers>
        <mapper class="com.song.dao.BookMapper"/>
    </mappers>

</configuration>

编写数据库对应的实体类 com.kuang.pojo.Books （使用lombok插件）

@Data
@NoArgsConstructor
@AllArgsConstructor
public class Books {
    private int bookID;
    private String bookName;
    private int bookCounts;
    private String detail;
}

编写 Dao 层的 Mapper 接口

public interface BookMapper {

    //增加一本书
    int addBook(Books books);

    //根据 id 删除一本书
    int deleteBookById(@Param("bookId") int id);

    //更新一本书
    int updateBook(Books books);

    //根据 id 查询一本书
    Books queryBookById(@Param("bookId") int id);

    //查询全部书
    List<Books> queryAllBooks();

	//根据 name 查询一本书
    Books queryBookByName(@Param("bookName") String bookName);
}

编写接口对应的 Mapper.xml 文件 BookMapper.xml

需要配置到 MyBatis 的核心配置文件中

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.song.dao.BookMapper">

    <!--增加一个Book-->
    <insert id="addBook" parameterType="Books">
        insert into ssmbuild.books (bookName, bookCounts, detail)
        values (#{bookName}, #{bookCounts}, #{detail});
    </insert>

    <!--根据id删除一个Book-->
    <delete id="deleteBookById" parameterType="_int">
        delete from ssmbuild.books
        where bookID = #{bookId}
    </delete>

    <!--更新Book-->
    <update id="updateBook" parameterType="Books">
        update ssmbuild.books
        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="Books">
        select * from ssmbuild.books
        where bookID = #{bookId};
    </select>

    <!--查询全部Book-->
    <select id="queryAllBooks" resultType="Books">
        select * from ssmbuild.books;
    </select>

    <!--根据name查询,返回一个Book-->
    <select id="queryBookByName" resultType="Books">
        select * from ssmbuild.books where bookName = #{bookName};
    </select>

</mapper>

编写 Service 层的接口和实现类

接口 BookService

public interface BookService {
    //增加一本书
    int addBook(Books books);

    //删除一本书
    int deleteBookById(int id);

    //更新一本书
    int updateBook(Books books);

    //查询一本书
    Books queryBookById(int id);

    //查询全部书
    List<Books> queryAllBooks();

    Books queryBookByName(String bookName);
}

实现类 BookServiceImpl

public class BookServiceImpl implements BookService {

    // Service 调用 dao层: 把 dao 层组合进来
    private BookMapper bookMapper;

    public void setBookMapper(BookMapper bookMapper) {
        this.bookMapper = bookMapper;
    }

    public int addBook(Books books) {
        return bookMapper.addBook(books);
    }

    public int deleteBookById(int id) {
        return bookMapper.deleteBookById(id);
    }

    public int updateBook(Books books) {
        return bookMapper.updateBook(books);
    }

    public Books queryBookById(int id) {
        return bookMapper.queryBookById(id);
    }

    public List<Books> queryAllBooks() {
        return bookMapper.queryAllBooks();
    }

    public Books queryBookByName(String bookName) {
        return bookMapper.queryBookByName(bookName);
    }
}

5、Spring层

Spring 整合 Mybatis 的相关的配置文件 spring-dao.xml，这里的数据源使用 c3p0 连接池

<?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:database.properties"/>

    <!--2. 连接池
        dbcp：半自动化操作，不能自动连接
        c3p0：自动化操作（自动化的加载配置文件，并且可以自动设置到对象中）
        druid：
        hikari：springboot 2.x 默认集成
    -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <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. SqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <!--绑定配置文件-->
        <property name="configLocation" value="classpath:mabatis-config.xml"/>
    </bean>

    <!--4. 配置 dao 接口扫描包，动态的实现了 Dao接口可以接入到 Spring容器中-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!--注入 sqlSessionFactory-->
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <!--要扫描的dao包-->
        <property name="basePackage" value="com.song.dao"/>
    </bean>

</beans>

Spring 整合 service 层 spring-service.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"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       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
       http://www.springframework.org/schema/aop
       https://www.springframework.org/schema/aop/spring-aop.xsd
       http://www.springframework.org/schema/tx
       http://www.springframework.org/schema/tx/spring-tx.xsd">

    <!--1. 扫描 service下的包-->
    <context:component-scan base-package="com.song.service"/>

    <!--2. 将所有的业务类注入到 spring-->
    <bean id="BookServiceImpl" class="com.song.service.BookServiceImpl">
        <property name="bookMapper" ref="bookMapper"/>
    </bean>

    <!--3. 声明式事务-->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <!--注入数据源-->
        <property name="dataSource" ref="dataSource"/>
    </bean>

    <!--4. aop 事务支持-->
    <!--结合AOP，实现事务的织入-->
    <!--配置事务通知-->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <!--给哪些方法配置事务-->
        <!--配置事务的传播特性  propagation-->
        <tx:attributes>
            <tx:method name="*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>

    <!--配置事务切入-->
    <aop:config>
        <aop:pointcut id="txPointCut" expression="execution(* com.song.dao.*.*(..))"/>
        <aop:advisor advice-ref="txAdvice" pointcut-ref="txPointCut"/>
    </aop:config>

</beans>

6、SpringMVC 层

**web.xml **中配置 DispatcherServlet 和乱码过滤

<?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>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:applicationContext.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <!--乱码过滤-->
    <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 version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       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/mvc
       http://www.springframework.org/schema/mvc/spring-mvc.xsd
       http://www.springframework.org/schema/context
       https://www.springframework.org/schema/context/spring-context.xsd">


    <!--1.开启SpringMVC注解驱动-->
    <mvc:annotation-driven/>
    <!--2.静态资源过滤-->
    <mvc:default-servlet-handler/>
    <!--3.扫描包：controller（扫描web相关的bean）-->
    <context:component-scan base-package="com.song.controller"/>


    <!--4.视图解析器-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

</beans>

Spring 配置整合文件，applicationContext.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="classpath:spring-dao.xml"/>
    <import resource="classpath:spring-service.xml"/>
    <import resource="classpath:spring-mvc.xml"/>

</beans>

配置文件结束，接下来要进行 Controller 和视图层编写，实现功能

7、Controller 和视图层（实现功能）

7.1 查询全部书籍

编写 BookController 类

@Controller
@RequestMapping("/book")
public class BookController {
    // Controller调service层
    @Autowired
    @Qualifier("BookServiceImpl")
    private BookService bookService;

    // 查询全部的书籍
    @RequestMapping("/allBook")
    public String list(Model model){
        List<Books> list = bookService.queryAllBooks();
        model.addAttribute("list", list);
        return "allBook";  // localhost:8080/book/allBook.jsp
    }
}

编写首页 index.jsp

点击首页的超链接 进入书籍页面 ，DispatcherServlet 会接收并拦截这个超链接的 url，通过 SpringMVC 中的处理器映射器和适配器，BookController 根据 /book/allBook 执行 list() 方法，进行业务处理并返回模型数据，最后通过视图解析器渲染视图，将结果显示在 allBook.jsp 页面

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
  <head>
    <title>首页</title>

    <style>
        a{
            text-decoration: none;
            color: black;
            font-size: 18px;
        }
        h3{
            width: 180px;
            heigh: 38px;
            margin: 100px auto;
            text-align: center;
            line-height: 38px;
            background: deepskyblue;
            border-radius: 5px;
        }
    </style>

  </head>
  <body>

  <h3>
    <a href="${pageContext.request.contextPath}/book/allBook">进入书籍页面</a>
  </h3>

  </body>
</html>

查询全部书籍后跳转到的页面 allBook.jsp，会将 Controller 中的 list 遍历出来放到一个表格中

使用 Bootstrap 美化界面

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>书籍展示页面</title>

    <%--Bootstrap美化界面--%>
    <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">

</head>
<body>

<div class="container">

    <div class="row clearfix">
        <div class="col-md-12 column">
            <div class="page-header">
                <h1>
                    <small>书籍列表 —————— 显示所有书籍</small>
                </h1>
            </div>
        </div>

        <div class="row">
            <div class="col-md-4 column">
                <%--toAddBook--%>
                <a class="btn btn-primary" href="${pageContext.request.contextPath}/book/toAddBook">新增书籍</a>
                <a class="btn btn-primary" href="${pageContext.request.contextPath}/book/allBook">显示全部书籍</a>
            </div>
            <div class="col-md-4 column"></div>
            <div class="col-md-4 column">
                <%--查询书籍--%>
                <form action="${pageContext.request.contextPath}/book/queryBook" method="post" style="float:right" class="form-inline">
                    <span style="color:red;font-weight:bold">${error}</span>
                    <input type="text" name="queryBookName" class="form-control" placeholder="请输入要查询的书籍名称">
                    <input type="submit" value="查询" class="btn btn-primary">
                </form>
            </div>
        </div>

    </div>

    <div class="row clearfix">
        <div class="col-md-12 column">
            <table class="table table-hover table-striped">
                <thead>
                    <tr>
                        <th>书籍编号</th>
                        <th>书籍名称</th>
                        <th>书籍数量</th>
                        <th>书籍详情</th>
                        <th>操作</th>
                    </tr>
                </thead>

                <%--书籍从数据库查询出来，从list中遍历出来：foreach--%>
                <tbody>
                    <c:forEach var="book" items="${list}">
                        <tr>
                            <td>${book.bookID}</td>
                            <td>${book.bookName}</td>
                            <td>${book.bookCounts}</td>
                            <td>${book.detail}</td>
                            <td>
                                <a href="${pageContext.request.contextPath}/book/toUpdate?id=${book.bookID}">修改</a>
                                &nbsp; | &nbsp;
                                <a href="${pageContext.request.contextPath}/book/deleteBook/${book.bookID}">删除</a>
                            </td>
                        </tr>
                    </c:forEach>
                </tbody>
            </table>
        </div>
    </div>
</div>


</body>
</html>

7.2 添加书籍

前面的 BookController 类中添加【跳转到增加书籍页面】和【添加书籍的请求】的方法。

在 allBook.jsp 页面添加一个 新增书籍 超链接，点击这个按钮之后根据请求路径 /book/toAddBook 跳转到 addBook.jsp 界面。

添加完书籍之后，根据请求路径 /book/addBook 会重定向到 显示全部书籍 allBook.jsp 页面。

<a class="btn btn-primary" href="${pageContext.request.contextPath}/book/toAddBook">新增书籍</a>

// 跳转到增加书籍页面
@RequestMapping("/toAddBook")
public String toAddPage(){
    return "addBook";
}

// 添加书籍的请求
@RequestMapping("/addBook")
public String addBook(Books books){
    System.out.println("addBook=>"+ books);
    bookService.addBook(books);
    return "redirect:/book/allBook"; //重定向到@RequestMapping("/allBook")请求
}

添加书籍页面：addBook.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>

    <%--Bootstrap美化界面--%>
    <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>

<div class="container">

    <div class="row clearfix">
        <div class="col-md-12 column">
            <div class="page-header">
                <h1>
                    <small>新增书籍</small>
                </h1>
            </div>
        </div>
    </div>

    <form action="${pageContext.request.contextPath}/book/addBook" method="post">
        <div class="form-group">
            <label>书籍名称：</label>
            <input type="text" name="bookName" class="form-control" required>
        </div>
        <div class="form-group">
            <label>书籍数量：</label>
            <input type="text" name="bookCounts" class="form-control" required>
        </div>
        <div class="form-group">
            <label>书籍详情：</label>
            <input type="text" name="detail" class="form-control" required>
        </div>
        <div class="form-group">
            <input type="submit" class="form-control" value="添加">
        </div>
    </form>

</div>

</body>
</html>

7.3 修改书籍信息

前面的 BookController 类中添加【跳转到修改书籍页面】和【修改书籍的请求】的方法。

在 allBook.jsp 页面的表格中添加一列【操作】的选项，每一行有【修改和删除】的超链接，点击之后会对某个对象进行相应操作。

对于【修改】操作，点击之后根据 /book/toUpdate 跳转到修改页面 updateBook.jsp。注意：要在点击按钮时自动获取 bookID 参数，并将其作为请求参数传入控制器，这样，可以根据 bookID 查询出对应书籍的信息显示在修改页面。

修改后根据请求 /book/updateBook 会将新的 book 对象传入 updateBook，该方法会调用业务层和 dao 层的 update 方法和数据库进行交互，执行完这些操作后重定向到 allBook.jsp

<th>操作</th>

<td>
    <a href="${pageContext.request.contextPath}/book/toUpdate?id=${book.bookID}">修改</a>
    &nbsp; | &nbsp;
    <a href="${pageContext.request.contextPath}/book/deleteBook/${book.bookID}">删除</a>
</td>

// 跳转到修改页面
@RequestMapping("/toUpdate")
public String toUpdatePage(int id, Model model){
    Books books = bookService.queryBookById(id);
    model.addAttribute("QBooks",books);  // QBooks信息会显示在前端
    return "updateBook";
}

// 修改书籍
@RequestMapping("/updateBook")
public String updateBook(Books books){  // 前端修改后的数据传入
    System.out.println("updateBook=>" + books);
    int i = bookService.updateBook(books);
    if(i>0){
        System.out.println("添加books成功" + books);
    }
    return "redirect:/book/allBook";
}

修改书籍页面 updateBook.jsp

注意：别忘了传递 bookID，否则会传递 bookID=0 修改不成功

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>修改书籍</title>

    <%--Bootstrap美化界面--%>
    <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>

<div class="container">

    <div class="row clearfix">
        <div class="col-md-12 column">
            <div class="page-header">
                <h1>
                    <small>修改书籍</small>
                </h1>
            </div>
        </div>
    </div>

    <form action="${pageContext.request.contextPath}/book/updateBook" method="post">
        <%--出现的问题：提交了修改的SQL请求，但是修改失败，初次考虑是事务问题，配置完毕，依旧失败
            看SQL语句能否执行成功：SQL执行失败，修改未完成--%>、、
        <%--前端传递隐藏域--%>
        <input type="hidden" name="bookID" value="${QBooks.bookID}">

        <div class="form-group">
            <label>书籍名称：</label>
            <input type="text" name="bookName" class="form-control" value="${QBooks.bookName}" required>
        </div>
        <div class="form-group">
            <label>书籍数量：</label>
            <input type="text" name="bookCounts" class="form-control" value="${QBooks.bookCounts}" required>
        </div>
        <div class="form-group">
            <label>书籍详情：</label>
            <input type="text" name="detail" class="form-control" value="${QBooks.detail}" required>
        </div>
        <div class="form-group">
            <input type="submit" class="form-control" value="修改">
        </div>
    </form>

</div>

</body>
</html>

7.4 删除书籍

allBook.jsp 页面添加删除的超链接，点击之后会发送 /book/deleteBook/${book.bookID} 请求
```
<a href="${pageContext.request.contextPath}/book/deleteBook/${book.bookID}">删除</a>
```

前面的 BookController 类中添加【根据 id 删除书籍】的方法。

该方法接收到请求参数，调用 service 和 dao 层执行删除操作，最后重定向到 allBook.jsp

// 删除书籍 这里使用了RestFul风格
@RequestMapping("/deleteBook/{bookId}")
public String deleteBook(@PathVariable("bookId") int id){
    bookService.deleteBookById(id);
    return "redirect:/book/allBook";
}

7.5 搜索书籍（根据名称查询书籍）

在 allBook.jsp 页面添加一个 form 表单，输入书籍名称后点击查询会发送 /book/queryBook 请求，Controller 会根据这个请求做出相应处理。

<%--查询书籍--%>
<form action="${pageContext.request.contextPath}/book/queryBook" method="post" style="float:right" class="form-inline">
    <span style="color:red;font-weight:bold">${error}</span>
    <input type="text" name="queryBookName" class="form-control" placeholder="请输入要查询的书籍名称">
    <input type="submit" value="查询" class="btn btn-primary">
</form>

前面的 BookController 类中添加【根据名称查询书籍】的方法。

查询完成之后转发到 allBook.jsp 页面，输入为空或者输入不匹配会显示“未查到”，仍显示全部书籍。

// 查询书籍
@RequestMapping("/queryBook")
public String queryBook(String queryBookName, Model model){
    Books books = bookService.queryBookByName(queryBookName);
    List<Books> list = new ArrayList<Books>();
    list.add(books);

    //查询优化
    if(books == null){
        list = bookService.queryAllBooks();
        model.addAttribute("error", "未查到");
    }

    model.addAttribute("list", list);
    return "allBook";
}