SSM框架整合
1、环境要求(笔者自己的环境)
环境:
- IDEA 2019.03
- MySQL 8.0.22
- Tomcat 9
- Maven 3.6
要求:熟练掌握MySQL 数据库,Spring,JavaWeb及Mybatis知识,简单的前端知识
如果前端知识拿不出手,可以直接利用工具生成前端代码:BootStrap可视化布局
2、准备工作
创建一个存放书籍的数据库表
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
-
新建一个普通的Maven项目,添加web支持(也可以直接创建一个Maven web项目工程)并配置Tomcat
-
导入相关的pom依赖
<!-- 导入依赖: 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>4.11</version> </dependency> <!--mysql 数据库驱动--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.22</version> </dependency> <!--数据库连接池c3p0--> <!-- https://mvnrepository.com/artifact/com.mchange/c3p0 --> <dependency> <groupId>com.mchange</groupId> <artifactId>c3p0</artifactId> <version>0.9.5.2</version> </dependency> <!--servlet--> <dependency> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> <version>2.5</version> </dependency> <!--jsp--> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>jsp-api</artifactId> <version>2.2</version> </dependency> <!--jstl--> <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>5.2.0.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>5.2.0.RELEASE</version> </dependency> <!-- 导入lombok--> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.16.10</version> </dependency> </dependencies>
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pom.xml添加静态资源过滤配置
<!-- 静态资源导出问题--> <!--在build中配置resources,来防止我们资源导出失败的问题--> <build> <resources> <resource> <directory>src/main/resources</directory> <includes> <include>**/*.properties</include> <include>**/*.xml</include> </includes> <filtering>true</filtering> </resource> <resource> <directory>src/main/java</directory> <includes> <include>**/*.properties</include> <include>**/*.xml</include> </includes> <filtering>true</filtering> </resource> </resources> </build> <!-- 解决配置文件中有中文而导致的错误--> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties>
-
建立项目的包结构
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mybatis配置文件(初始)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>
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Spring配置文件(初始)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 https://www.springframework.org/schema/beans/spring-beans.xsd"> </beans>
4、Mybatis层整合
1、数据库配置文件db.properties
jdbc.driver=com.mysql.jdbc.Driver
# 如果使用的时mysql8.0+,需要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&serverTimezone=Asia/Shanghai
jdbc.username=root
jdbc.password=root
2、IDEA中打开指定的数据库
3、编写mybatis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资源配置-->
<configuration>
<!--设置日志-->
<settings>
<setting name="logImpl" value="STDOUT_LOGGING"/>
</settings>
<!--别名-->
<typeAliases>
<package name="com.liuxingwu.pojo"/>
</typeAliases>
<mappers>
<mapper class="com.liuxingwu.dao.BookMapper"/>
</mappers>
</configuration>
4、编写数据库对应的实体类(pojo包)
偷懒的方式:需要导入lombok依赖,如果idea没有事先下载lombok插件的话还需要下载后重启idea
package com.liuxingwu.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
/**
* @author saodisheng
* @Date 2021/3/5
*/
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Books {
private int bookID;
private String bookName;
private int bookCounts;
private String detail;
}
5、编写Dao层的Mapper接口
package com.liuxingwu.dao;
import com.liuxingwu.pojo.Books;
import org.apache.ibatis.annotations.Param;
import java.awt.print.Book;
import java.util.List;
/**
* @author saodisheng
* @Date 2021/3/5
*/
public interface BookMapper {
// 增加一本书
int addBook(Books books);
// 删除一本书
int deleteBook(int id);
// 更新一本书
int updateBook(Books books);
// 查询一本数据
Books queryBookById(@Param("bookId") int id);
// 查询全部书
List<Books> queryAllBooks();
}
6、编写接口对应的Mapper.xml文件
当然也可以通过注解实现,这里使用的是XML配置文件实现
<?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">
<!-- configuration资源配置-->
<mapper namespace="com.liuxingwu.dao.BookMapper">
<!-- 增加一本书-->
<insert id="addBook" parameterType="Books">
insert into ssmbuild.books (bookName, bookCounts, detail)
values (#{bookName}, #{bookCounts}, #{detail})
</insert>
<!-- 删除一本书-->
<delete id="deleteBook" >
delete from ssmbuild.books where bookID = #{bookId}
</delete>
<!-- 更新一本书-->
<update id="updateBook" parameterType="Books">
update ssmbuild.books
set bookName = #{bookName}, bookCounts = #{bookCounts}, detail = #{detail}
where bookID = #{bookID}
</update>
<!-- 查询一本书-->
<select id="queryBookById" resultType="Books">
select * from ssmbuild.books where bookID = #{bookId}
</select>
<!-- 查询全部书-->
<select id="queryAllBooks" resultType="Books">
select * from ssmbuild.books
</select>
</mapper>
7、业务层service层的接口及其实现类
接口
package com.liuxingwu.service;
import com.liuxingwu.pojo.Books;
import org.apache.ibatis.annotations.Param;
import java.util.List;
/**
* @author saodisheng
* @Date 2021/3/5
*/
public interface BookService {
// 增加一本书
int addBook(Books books);
// 删除一本书
int deleteBook(int id);
// 更新一本书
int updateBook(Books books);
// 查询一本数据
Books queryBookById(int id);
// 查询全部书
List<Books> queryAllBooks();
}
实现类
package com.liuxingwu.service;
import com.liuxingwu.dao.BookMapper;
import com.liuxingwu.pojo.Books;
import org.junit.Test;
import java.awt.print.Book;
import java.util.List;
/**
* @author saodisheng
* @Date 2021/3/5
*/
public class BookServiceImpl implements BookService {
// Service层要调用dao层的方法,因此需要将组合一个dao层的实例
private BookMapper bookMapper;
public void setBookMapper(BookMapper bookMapper) {
this.bookMapper = bookMapper;
}
public int addBook(Books books) {
return bookMapper.addBook(books);
}
public int deleteBook(int id) {
return bookMapper.deleteBook(id);
}
public int updateBook(Books books) {
System.out.println(books);
bookMapper.updateBook(books);
return 1;
}
public Books queryBookById(int id) {
return bookMapper.queryBookById(id);
}
public List<Books> queryAllBooks() {
return bookMapper.queryAllBooks();
}
}
5、Spring层整合
编写配置Spring配置文件,整合Mybatis
1、spring-dao.xml(整合dao层),这里使用的是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
https://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:db.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:
-->
<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的独有属性-->
<!--设置连接池的数量范围-->
<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"/>
<!--当获取连接失败时再重试次数-->
<property name="acquireRetryAttempts" value="2"/>
</bean>
<!-- 3.sqlSessionFactory-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<!--绑定Mybatis的配置文件-->
<property name="configLocation" value="classpath:mybatis-config.xml"/>
</bean>
<!--配置dao接口扫描包,动态地实现了Dao接口可以注入到Spring容器中-->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<!--注入sqlSessionFactory-->
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
<!--要扫描的包 dao层-->
<property name="basePackage" value="com.liuxingwu.dao"/>
</bean>
</beans>
2、spring-service.xml(整合Service层)
<?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
https://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
https://www.springframework.org/schema/context/spring-context.xsd">
<!--1.扫描service下的包 业务层-->
<context:component-scan base-package="com.liuxingwu.service"/>
<!--2.将所有的业务类注入到Spring,可以通过配置,或者注解-->
<bean id="BookServiceImpl" class="com.liuxingwu.service.BookServiceImpl">
<property name="bookMapper" ref="bookMapper"/>
</bean>
<!--3.声明式事务配置-->
<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-->
</beans>
6、SpringMVC层整合
1、SpringMVC配置文件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:cnntext="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
<!-- 1.注解驱动-->
<mvc:annotation-driven/>
<!-- 2.打开静态资源过滤-->
<mvc:default-servlet-handler/>
<!-- 3.扫描包:Controller 控制层-->
<cnntext:component-scan base-package="com.liuxingwu.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>
2、合并资源配置文件 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
https://www.springframework.org/schema/beans/spring-beans.xsd">
<import resource="spring-dao.xml"/>
<import resource="spring-service.xml"/>
<import resource="spring-mvc.xml"/>
</beans>
3、配置web.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 SpringMVC控制中心 -->
<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>
<!--自定义session的失效时间-->
<session-config>
<session-timeout>15</session-timeout>
</session-config>
</web-app>
截止目前,基本的ssm框架已经整合完毕了。
7、Controller和视图层的编写
1、查询全部书籍
-
控制层:BookController
package com.liuxingwu.controller; import com.liuxingwu.pojo.Books; import com.liuxingwu.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; /** * @author saodisheng * @Date 2021/3/5 */ @Controller @RequestMapping("/book") public class BookController { // Controller调用Service层 @Autowired @Qualifier("BookServiceImpl") private BookService bookService ; // 查询全部的书籍,并且返回一个书籍展示页面 @RequestMapping("/allbook") public String list(Model model) { List<Books> list = bookService.queryAllBooks(); model.addAttribute("list", list); return "allBook"; } }
-
编写首页index.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>首页</title> <style> a{ text-decoration: none; /*去除链接的下划线*/ color: black; /*设置链接字体颜色为黑色*/ font-size: 18px; /*设置字体大小*/ } h3{ width: 180px; height: 38px; margin: 100px auto; /*设置外边距*/ text-align: center; /*居中*/ line-height: 38px; background: deepskyblue; border-radius: 5px; /*圆边框*/ } </style> </head> <body> <h3> <a href="${pageContext.request.contextPath}/book/allbook">进入书籍页面</a> </h3> </body> </html>
-
书籍列表界面allbook.jsp(也是主要界面)
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>书籍展示</title> <%-- 美化界面--%> <!-- 新 Bootstrap 核心 CSS 文件 --> <link href="https://cdn.staticfile.org/twitter-bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet"> </head> <body> <div class="container"> <div class="row clearfix"> <div class="col-md-12 column"> <h1> <small>书籍列表————显示所有书籍</small> </h1> </div> </div> <div class="row"> <div class="col-md-4 cloumn"> <!--toAddBook--> <a class="btn btn-primary" href="${pageContext.request.contextPath}/book/toAddBook">新增书籍</a> <a class="btn btn-primary" href="${pageContext.request.contextPath}/book/allbook">显示所有书籍</a> </div> <div class="col-md-8 cloumn"> <!--查询书籍--> <form class="form-inline" action="${pageContext.request.contextPath}/book/queryBook" method="post" style="float:right"> <span style="color: red">${error}</span> <input type="text" name="queryBookName" class="form-control" placeholder="请输入要查询的书籍名称"> <input type="submit" value="查询" class="btn btn-primary"> </form> </div> </div> <div class="row clearfix"> <div class="col-md-12 cloumn"> <table class="table table-hover table-striped"> <thead> <tr> <th>书籍编号</th> <th>书籍名称</th> <th>书籍数量</th> <th>书籍详情</th> <th>操作</th> </tr> </thead> <%-- 书籍从数据库查询出来,从这个list中遍历出来:foreach--%> <tbody> <c:forEach var="book" items="${list}"> <tr> <td>${book.bookID}</td> <td>${book.bookName}</td> <td>${book.bookCounts}</td> <td>${book.detail}</td> <td> <a href="${pageContext.request.contextPath}/book/toUpdateBook?bookID=${book.bookID}">修改</a> <%--添加空格--%> | <a href="${pageContext.request.contextPath}/book/deleteBook/${book.bookID}">删除</a> </td> </tr> </c:forEach> </tbody> </table> </div> </div> </div> <%--<h1>书籍展示</h1>--%> </body> </html>
2、添加数据
-
BookController
// 跳转到添加书籍页面 @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") }
-
添加书籍页面:addBook.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>新增书籍</title> <%-- 美化界面--%> <!-- 新 Bootstrap 核心 CSS 文件 --> <link href="https://cdn.staticfile.org/twitter-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"> <h1> <small>新增书籍</small> </h1> </div> </div> <form action="${pageContext.request.contextPath}/book/addBook" method="post"> <div class="form-group"> <label>书籍名称:</label> <input type="text" name="bookName" class="form-control" required> </div> <div class="form-group"> <label>书籍数量:</label> <input type="text" name="bookCounts" class="form-control" required> </div> <div class="form-group"> <label>书籍描述:</label> <input type="text" name="detail" class="form-control" required> </div> <div class="form-group"> <input type="submit" class="form-control" value="添加"> </div> </form> </div> </body> </html>
3、修改书籍
-
BookController
// 跳转到修改书籍页面 // 接收前端传来的bookID,通过bookID查询指定的书籍 @RequestMapping("/toUpdateBook") public String toUpdatePage(int bookID, Model model) { Books books = bookService.queryBookById(bookID); model.addAttribute("QBook", books); return "updateBook"; } // 修改书籍的请求 @RequestMapping("/updateBook") public String updateBook(Books books) { System.out.println("updateBook=>" + books); bookService.updateBook(books); // System.out.println("修改成功"); return "redirect:/book/allbook"; // 重定向到@RequestMapping("/allbook") }
-
修改页面:updateBook.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>修改书籍</title> <%-- 美化界面--%> <!-- 新 Bootstrap 核心 CSS 文件 --> <link href="https://cdn.staticfile.org/twitter-bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet"> </head> <body> <div class="container"> <div class="row clearfix"> <div class="col-md-12 column"> <h1> <small>修改书籍</small> </h1> </div> </div> <form action="${pageContext.request.contextPath}/book/updateBook" method="post"> <%--出现的问题:提交了修改请求,但修改失败 原因是修改需要主键,但之前没有传递相应的主键 --%> <%--前端传递隐藏于,这点容易忽略,从而造成500错误--%> <input type="hidden" name="bookID" value="${QBook.bookID}"> <div class="form-group"> <label>书籍名称:</label> <input type="text" name="bookName" class="form-control" value="${QBook.bookName}" required> </div> <div class="form-group"> <label>书籍数量:</label> <input type="text" name="bookCounts" class="form-control" value="${QBook.bookCounts}" required> </div> <div class="form-group"> <label>书籍描述:</label> <input type="text" name="detail" class="form-control" value="${QBook.detail}" required> </div> <div class="form-group"> <input type="submit" class="form-control" value="修改"> </div> </form> </div> </body> </html>
4、删除书籍
-
BookController
// 删除书籍 @RequestMapping("/deleteBook/{bookid}") public String deleteBook(@PathVariable("bookid") int bookID) { bookService.deleteBook(bookID); return "redirect:/book/allbook"; // 重定向到@RequestMapping("/allbook") }
8、体会一下在搭建好的ssm框架中添加新功能的步骤
添加一个图书查询的功能
1、dao接口BookMapper
之所以考虑返回一个列表是因为查询的实现采用的是模糊查询
// 通过书籍名称查询一本书名
List<Books> queryBook(String bookName);
2、BookMapper接口对应的配置文件BookMapper.xml
模糊查询
<!--通过书名查询书籍-->
<select id="queryBook" parameterType="string" resultType="Books">
select * from ssmbuild.books where bookName like "%"#{bookName}"%"
</select>
3、业务层service接口BookService
// 通过书名查询书籍
List<Books> queryBook(String bookName);
4、业务层接口实现类
public List<Books> queryBook(String bookName) {
return bookMapper.queryBook(bookName);
}
5、控制层BookController
// 查询书籍
@RequestMapping("/queryBook")
public String queryBook(String queryBookName, Model model) {
List<Books> booksList = bookService.queryBook(queryBookName);
model.addAttribute("list", booksList);
if (booksList.size() == 0) {
model.addAttribute("error", "为找到相关书籍");
}
return "allBook";
}