Spring MVC
参考视频:B站狂神,写这个只是方便个人复习,怎么写是我自己的事,我能看懂就行,没要求非要让你看!白嫖还挑刺,是很没有风度的事情。希望做个有风度的“五好青年”!
7、整合SSM框架
环境要求:
- IDEA 2020.2
- MySQL 5.7.19
- Tomcat 8.5
- Maven 3.6
技术要求:
- 需要熟练掌握MySQL数据库,Spring,JavaWeb及MyBatis知识,简单的前端知识;
数据库环境:
创建一个存放书籍数据的数据库表:
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' );
1.基本环境搭建
- 新建一Maven项目!ssmbuild , 添加web的支持
- 导入相关的pom依赖!
<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 -->
<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>
</dependencies>
- Maven资源过滤设置
<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.github.subei.pojo
- com.github.subei.dao
- com.github.subei.service
- com.github.subei.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>
2.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。
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
<?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>
<typeAliases>
<package name="com.github.subei.pojo"/>
</typeAliases>
<mappers>
<mapper class="com.github.subei.dao.BookMapper"/>
</mappers>
</configuration>
- 编写数据库对应的实体类 com.github.subei.pojo.Books,使用lombok插件!
package com.github.subei.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Books {
private int bookID;
private String bookName;
private int bookCounts;
private String detail;
}
- 编写Dao层的 Mapper接口!
package com.github.subei.dao;
import com.github.subei.pojo.Books;
import org.apache.ibatis.annotations.Param;
import java.util.List;
public interface BookMapper {
// 增加一个Book
int addBook(Books book);
// 根据id删除一个Book
int deleteBookById(@Param("bookID") int id);
// 更新一个Book
int updateBook(Books books);
// 根据id查询,返回一个Book
Books queryBookById(@Param("bookID") int id);
// 查询全部Book,返回list集合
List<Books> queryAllBook();
}
- 编写接口对应的Mapper.xml 文件。需要导入MyBatis的包;
<?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.github.subei.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="queryAllBook" resultType="Books">
SELECT * from ssmbuild.books;
</select>
</mapper>
- 编写Service层的接口和实现类
- 接口:
package com.github.subei.service;
import com.github.subei.pojo.Books;
import java.util.List;
// BookService:底下需要去实现,调用dao层
public interface BookService {
// 增加一个Book
int addBook(Books book);
// 根据id删除一个Book
int deleteBookById(int id);
// 更新Book
int updateBook(Books books);
// 根据id查询,返回一个Book
Books queryBookById(int id);
// 查询全部Book,返回list集合
List<Books> queryAllBook();
}
- 实现类:
package com.github.subei.service;
import com.github.subei.dao.BookMapper;
import com.github.subei.pojo.Books;
import java.util.List;
public class BookServiceImpl implements BookService {
// 调用dao层的操作,设置一个set接口,方便Spring管理
private BookMapper bookMapper;
public void setBookMapper(BookMapper bookMapper) {
this.bookMapper = bookMapper;
}
public int addBook(Books book) {
return bookMapper.addBook(book);
}
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> queryAllBook() {
return bookMapper.queryAllBook();
}
}
OK,到此,底层需求操作编写完毕!
3.Spring层
-
配置Spring整合MyBatis,这里数据源使用c3p0连接池;
-
编写Spring整合Mybatis的相关的配置文件;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">
<!-- 配置整合mybatis -->
<!-- 1.关联数据库文件 -->
<context:property-placeholder location="classpath:database.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MyBaties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.github.subei.dao"/>
</bean>
</beans>
- Spring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 http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 扫描service相关的bean -->
<context:component-scan base-package="com.github.subei.service" />
<!--BookServiceImpl注入到IOC容器中-->
<bean id="BookServiceImpl" class="com.github.subei.service.BookServiceImpl">
<property name="bookMapper" ref="bookMapper"/>
</bean>
<!-- 配置事务管理器 -->
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<!-- 注入数据库连接池 -->
<property name="dataSource" ref="dataSource" />
</bean>
</beans>
4.SpringMVC层
- 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-->
<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 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:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd">
<!-- 配置SpringMVC -->
<!-- 1.开启SpringMVC注解驱动 -->
<mvc:annotation-driven />
<!-- 2.静态资源默认servlet配置-->
<mvc:default-servlet-handler/>
<!-- 3.配置jsp 显示ViewResolver视图解析器 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
<property name="prefix" value="/WEB-INF/jsp/" />
<property name="suffix" value=".jsp" />
</bean>
<!-- 4.扫描web相关的bean -->
<context:component-scan base-package="com.github.subei.controller" />
</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="spring-dao.xml"/>
<import resource="spring-service.xml"/>
<import resource="spring-mvc.xml"/>
</beans>
配置文件,暂时结束!Controller 和 视图层编写
5.案例实现
- BookController 类编写 , 方法一:查询全部书籍
package com.github.subei.controller;
import com.github.subei.pojo.Books;
import com.github.subei.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.RequestMapping;
import java.util.List;
@Controller
@RequestMapping("/book")
public class BookController {
@Autowired
@Qualifier("BookServiceImpl")
private BookService bookService;
@RequestMapping("/allBook")
public String list(Model model) {
List<Books> list = bookService.queryAllBook();
model.addAttribute("list", list);
return "allBook";
}
}
2、编写首页 index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<!DOCTYPE HTML>
<html>
<head>
<title>首页</title>
<style type="text/css">
a {
text-decoration: none;
color: black;
font-size: 18px;
}
h3 {
width: 180px;
height: 38px;
margin: 100px auto;
text-align: center;
line-height: 38px;
background: deepskyblue;
border-radius: 4px;
}
</style>
</head>
<body>
<h3>
<a href="${pageContext.request.contextPath}/book/allBook">点击进入列表页</a>
</h3>
</body>
</html>
- 书籍列表页面 allbook.jsp
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>书籍列表</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- 引入 Bootstrap -->
<link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>
<div class="container">
<div class="row clearfix">
<div class="col-md-12 column">
<div class="page-header">
<h1>
<small>书籍列表 —— 显示所有书籍</small>
</h1>
</div>
</div>
</div>
<div class="row">
<div class="col-md-4 column">
<a class="btn btn-primary" href="${pageContext.request.contextPath}/book/toAddBook">新增书籍</a>
</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>书籍名字</th>
<th>书籍数量</th>
<th>书籍详情</th>
<th>操作</th>
</tr>
</thead>
<tbody>
<c:forEach var="book" items="${requestScope.get('list')}">
<tr>
<td>${book.getBookID()}</td>
<td>${book.getBookName()}</td>
<td>${book.getBookCounts()}</td>
<td>${book.getDetail()}</td>
<td>
<a href="${pageContext.request.contextPath}/book/toUpdateBook?id=${book.getBookID()}">更改</a> |
<a href="${pageContext.request.contextPath}/book/del/${book.getBookID()}">删除</a>
</td>
</tr>
</c:forEach>
</tbody>
</table>
</div>
</div>
</div>
- BookController 类编写 , 方法二:添加书籍
@RequestMapping("/toAddBook")
public String toAddPaper() {
return "addBook";
}
@RequestMapping("/addBook")
public String addPaper(Books books) {
System.out.println(books);
bookService.addBook(books);
return "redirect:/book/allBook";
}
- 添加书籍页面:addBook.jsp
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>新增书籍</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- 引入 Bootstrap -->
<link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>
<div class="container">
<div class="row clearfix">
<div class="col-md-12 column">
<div class="page-header">
<h1>
<small>新增书籍</small>
</h1>
</div>
</div>
</div>
<form action="${pageContext.request.contextPath}/book/addBook" method="post">
书籍名称:<input type="text" name="bookName"><br><br><br>
书籍数量:<input type="text" name="bookCounts"><br><br><br>
书籍详情:<input type="text" name="detail"><br><br><br>
<input type="submit" value="添加">
</form>
</div>
- BookController 类编写 , 方法三:修改书籍
@RequestMapping("/toUpdateBook")
public String toUpdateBook(Model model, int id) {
Books books = bookService.queryBookById(id);
System.out.println(books);
model.addAttribute("book",books );
return "updateBook";
}
@RequestMapping("/updateBook")
public String updateBook(Model model, Books book) {
System.out.println(book);
bookService.updateBook(book);
Books books = bookService.queryBookById(book.getBookID());
model.addAttribute("books", books);
return "redirect:/book/allBook";
}
- 修改书籍页面 updateBook.jsp
<%--
Created by IntelliJ IDEA.
User: subei
Date: 2021/2/27
Time: 17:53
To change this template use File | Settings | File Templates.
--%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>修改信息</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- 引入 Bootstrap -->
<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>修改信息</small>
</h1>
</div>
</div>
</div>
<form action="${pageContext.request.contextPath}/book/updateBook" method="post">
<input type="hidden" name="bookID" value="${book.getBookID()}"/>
书籍名称:<input type="text" name="bookName" value="${book.getBookName()}"/>
书籍数量:<input type="text" name="bookCounts" value="${book.getBookCounts()}"/>
书籍详情:<input type="text" name="detail" value="${book.getDetail() }"/>
<input type="submit" value="提交"/>
</form>
</div>
- BookController 类编写 , 方法四:删除书籍
@RequestMapping("/del/{bookID}")
public String deleteBook(@PathVariable("bookID") int id) {
bookService.deleteBookById(id);
return "redirect:/book/allBook";
}
- 书籍查询功能
- 修改前端页面,allBook.jsp页面
<div class="col-md-4 column"></div>
<div class="form-inline">
<%-- 查询书籍 --%>
<form action="" method="" style="float: right">
<input type="text" name="queryBookName" class="form-control" placeholder="请输入需要查询的书籍名">
<input type="submit" value="查询" class="btn btn-primary">
</form>
</div>
- 修改DAO层:BookMapper.java
// 查询,搜索书籍
Books queryBookByName(@Param("bookName")String bookName);
- 修改DAO层:BookMapper.xml
<!--搜索Book-->
<select id="queryBookByName" resultType="Books">
SELECT * from ssmbuild.books where bookName = #{bookName};
</select>
- 修改service层:BookService.java
// 查询,搜索书籍
Books queryBookByName(String bookName);
- 修改service层:BookServiceImpl.java
public Books queryBookByName(String bookName) {
return bookMapper.queryBookByName(bookName);
}
- 修改controller层:BookController.java
// 查询书籍
@RequestMapping("/queryBook")
public String queryBook(String queryBookName,Model model){
Books books = bookService.queryBookByName(queryBookName);
List<Books> list = new ArrayList<Books>();
list.add(books);
model.addAttribute("list", list);
return "allBook";
}
- 修改前端:allBook.jsp
<div class="col-md-4 column"></div>
<div class="form-inline">
<%-- 查询书籍 --%>
<form action="${pageContext.request.contextPath}/book/queryBook" method="post" style="float: right">
<input type="text" name="queryBookName" class="form-control" placeholder="请输入需要查询的书籍名">
<input type="submit" value="查询" class="btn btn-primary">
</form>
</div>
- 运行测试:
如果查询失败,需要显示全部书籍页面?
- 修改前端页面allBook.jsp
<div class="row">
<div class="col-md-4 column">
<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="form-inline">
<%-- 查询书籍 --%>
<form action="${pageContext.request.contextPath}/book/queryBook" method="post" style="float: right">
<span style="color: red;font-weight: bold" >${error}</span>
<input type="text" name="queryBookName" class="form-control" placeholder="请输入需要查询的书籍名">
<input type="submit" value="查询" class="btn btn-primary">
</form>
</div>
</div>
- 修改后台BookController.java
// 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);
if(books==null){
list = bookService.queryAllBook();
model.addAttribute("error","未查到");
}
model.addAttribute("list", list);
return "allBook";
}
配置Tomcat,进行运行!
项目结构图: