Apache Maven 高级应用（Part A）

RiemannHypothesis

发布于 2022-09-26 14:05:39

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发布于 2022-09-26 14:05:39

文章被收录于专栏：Elixir

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一、Maven基础

Maven是一个项目管理工具。依赖管理既Maven对项目中的JAR包的管理过程，传统工程我们将JAR包放在项目中，而Maven工程将JAR包放在仓库中，项目中只引用JAR包的坐标。

Maven放置JAR包的地方称为仓库，仓库又分为本地仓库、远程仓库既私服和中央仓库；当启动一个Maven项目是，Maven工程会通过pom文件中的JAR包坐标到本地仓库查询JAR包，如果本地仓库没有对应的JAR包会自动到中央仓库或者远程仓库中下载JAR包

Maven常用的命令有：

clean：清除项目
compile：编译代码
test：测试代码
package：打包代码
install：在本地仓库中安装JAR包
deploy：上传到私服

Maven的生命周期

清理生命周期
默认生命周期
站点生命周期

二、 Maven 构建项目

搭建Maven项目

在数据中创建item表，SQL如下；

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for item
-- ----------------------------
DROP TABLE IF EXISTS `item`;
CREATE TABLE `item` (
  `id` int(10) NOT NULL AUTO_INCREMENT,
  `name` varchar(20) DEFAULT NULL,
  `price` float(10,0) DEFAULT NULL,
  `pic` varchar(40) DEFAULT NULL,
  `create_time` datetime DEFAULT NULL,
  `detail` varchar(200) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=70 DEFAULT CHARSET=utf8;

SET FOREIGN_KEY_CHECKS = 1;

使用IDEA创建一个maven项目maven-high-level，点击File-Add Framework Support添加Web Framework。

Maven的JAR包冲突解决方案

在pom文件中添加5.x版本的spring-context，spring-context本身包含了许多jar包

再增加一个spring-beans依赖，版本为4.x

<dependencies>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>5.3.16</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-beans</artifactId>
        <version>4.2.4.RELEASE</version>
    </dependency>
</dependencies>

查看pom.xml文件中maven依赖关系图

根据Maven依赖图可以看出spring-beans和spring-context都包含了spring-core，但是由于版本不同也导致了spring-core有两个版本，这就是Maven的JAR包冲突，但是从左侧可以确定Maven选择了5.x版本的spring-core。JAR冲突时Maven时如何选择的？

第一声明优先原则

在pom文件中颠倒两个版本依赖的顺序，改为4.x版本的spring-beans在第一位，5.x版本的spring-context在第二位

根据左侧Maven的JAR包列表可以确定Maven选择了4.x版本的spring-core。

这就是第一声明优先原则：哪个JAR包坐标在靠上的位置上，这个JAR包就是先声明的，先声明的JAR包就会优先进入项目中

路径近者优先原则

首先来明确两个概念

直接依赖：项目中直接引入的JAR包
传递依赖：项目中没有直接导入JAR包，可以通过项目直接依赖的JAR包传递到项目中去，spring-core就是传递依赖

直接在项目中加入spring-core的依赖，版本为4.2.8.RELEASE，不同于spring-context和spring-bean包含的spring-core的版本

可以看出Maven选择的是直接引入的spring-core的版本，既没有选择spring-context也没有选择spring-bean

直接导入spring-core，所依赖的版本就变成了直接导入的版本，没有直接导入的话就是用间接传递依赖的版本，间接传递依赖的版本又依赖于第一声明优先原则

路径近者优先原则：直接依赖路径比传递依赖路径近，最终进入项目的JAR包会是直接依赖的JAR包

exclusion标签排除JAR包

首先删除直接引入的spring-core 4.2.8.RELEASE，保持4.2.4.RELSEAS版本在第一位，5.3.16版本在第二位的情况下又想使用5.3.16版本的spring-core，这种情况下就可以使用exclusions标签，将4.x版本的spring-core排除掉

exclusion标签中不用写版本号默认使用上层的版本号。此时，Spring-core就变成5.3.16版本的了

推荐使用第三种方式

完成Maven项目搭建

pom文件中添加Maven依赖

<!-- 统一管理jar包版本 -->
<properties>
    <spring.version>5.3.16</spring.version>
    <slf4j.version>1.7.36</slf4j.version>
    <logback.version>1.2.11</logback.version>
    <shiro.version>1.8.0</shiro.version>
    <mysql.version>8.0.16</mysql.version>
    <mybatis.version>3.5.7</mybatis.version>
    <spring.security.version>5.6.1</spring.security.version>
    <project.build.sourceEncoding>
        UTF-8
    </project.build.sourceEncoding>
</properties>

<!-- 锁定jar包版本 -->
<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>${mybatis.version}</version>
        </dependency>
    </dependencies>
</dependencyManagement>

<!-- 项目依赖jar包 -->
<dependencies>
    <!-- spring -->
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjweaver</artifactId>
        <version>1.9.8</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-aop</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context-support</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-web</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-orm</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-beans</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>${mysql.version}</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>4.0.1</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>javax.servlet.jsp.jstl</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>

    <!-- log start -->
    <!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-classic -->
    <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-classic</artifactId>
        <version>${logback.version}</version>
    </dependency>

    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>${slf4j.version}</version>
    </dependency>
    <!-- log end -->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>${mybatis.version}</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis-spring</artifactId>
        <version>2.0.7</version>
    </dependency>
    <dependency>
        <groupId>com.github.pagehelper</groupId>
        <artifactId>pagehelper</artifactId>
        <version>5.3.0</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-web</artifactId>
        <version>${spring.security.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-config</artifactId>
        <version>${spring.security.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-core</artifactId>
        <version>${spring.security.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-taglibs</artifactId>
        <version>${spring.security.version}</version>
    </dependency>
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>1.1.14</version>
    </dependency>

    <dependency>
        <groupId>commons-fileupload</groupId>
        <artifactId>commons-fileupload</artifactId>
        <version>1.4</version>
    </dependency>

    <dependency>
        <groupId>commons-io</groupId>
        <artifactId>commons-io</artifactId>
        <version>2.11.0</version>
    </dependency>

    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.16.18</version>
        <scope>provided</scope>
    </dependency>
</dependencies>

Maven工程是可以分父子依赖关系的，凡是依赖别的项目后，拿到的都是别的项目的依赖包，属于传递依赖，为了放置直接依赖的JAR包覆盖传递依赖的JAR包，通常会使用dependencyManagement标签把JAR包锁住，这样的话直接依赖就无法覆盖间接依赖引入的JAR包

创建Mapper层、Service层和Controller层

根据item表的字段来创建Item实体类，新建entity包增加Item实体类

@Data
public class Item {

    private Integer id;
    private String name;
    private Double price;
    private String pic;
    private Date createTime;
    private String detail;
}

创建ItemMapper接口，新增mapper文件夹以及ItemMapper接口

public interface ItemMapper {

}

在resources目录下创建MyBatis全局配置文件

<?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>

    <settings>
        <!--开启驼峰命名-->
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
</configuration>

在resources目录下常见mappers文件夹，在mappers中创建MyBatis SQL Mapper XML文件

<?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.lilith.mapper.ItemMapper">

</mapper>

在resources目录下创建数据库连接配置文件db.properties

jdbc_driver=com.mysql.cj.jdbc.Driver
jdbc_url=jdbc:mysql://localhost:3306/test?useUnicode=true&amp;characterEncoding=utf8&amp;autoReconnect=true&amp;useSSL=false&amp;serverTimezone=Asia/Shanghai
jdbc_username=root
jdbc_password=root

在resources目录下创建logback.xml配置文件，用于打印执行的SQL

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
   <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
       <encoder>
           <pattern>[%thread] %d{HH:mm:ss.SSS} %-5level %logger{36} - %msg%n</pattern>
       </encoder>
   </appender>
    <root level="debug">
        <appender-ref ref="console"/>
    </root>
</configuration>

在WEB-INF下创建Spring MVC配置文件dispatcherServlet-servlet.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:util="http://www.springframework.org/schema/util"
       xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context"
       xmlns:aop="http://www.springframework.org/schema/aop" xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/util
        http://www.springframework.org/schema/util/spring-util-4.3.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/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:component-scan base-package="com.lilith" use-default-filters="false">
        <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>

    <!--配置试图解析器，自动拼接页面地址，自动在jsp页面前增加/WEB-INF/pages/-->
    <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/pages/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>

    <!-- 默认前端控制器是拦截所有资源（除过jsp），js文件就404了；要js文件的请求是交给tomcat处理的 -->
    <!-- 告诉SpringMVC，自己映射的请求就自己处理，不能处理的请求直接交给tomcat -->
    <!-- 静态资源能访问，动态映射的请求就不行 -->
    <mvc:default-servlet-handler/>
    <!-- springmvc可以保证动态请求和静态请求都能访问 -->
    <mvc:annotation-driven></mvc:annotation-driven>
</beans>

在resources目录下创建Spring配置文件application.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:util="http://www.springframework.org/schema/util"
       xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/util
        http://www.springframework.org/schema/util/spring-util-4.3.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd http://www.alibaba.com/schema/stat http://www.alibaba.com/schema/stat.xsd http://www.springframework.org/schema/tool http://www.springframework.org/schema/tool/spring-tool.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc.xsd">

    <!--扫描除了控制器之前的其他包-->
    <context:component-scan base-package="com.lilith">
        <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>
    <!--引用外部配置文件-->
    <context:property-placeholder location="classpath:db.properties"></context:property-placeholder>

    <!--数据库连接池配置-->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="${jdbc_driver}"/>
        <property name="url" value="${jdbc_url}" />
        <property name="username" value="${jdbc_username}"/>
        <property name="password" value="${jdbc_password}"/>
        <!--<property name="initialSize" value="${jdbc_initialSize}"/>-->
        <!--<property name="maxActive" value="${jdbc_maxActive}"/>-->
    </bean>

    <bean id="sqlSessionFactoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="configLocation" value="classpath:mybatis-config.xml"></property>
        <property name="dataSource" ref="dataSource"></property>
        <property name="mapperLocations" value="classpath:/mappers/*.xml"></property>
    </bean>

    <!--mapper层接口加入到Spring容器-->
    <bean id="mapperScannerConfigurer" class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!--指定接口所在的包-->
        <property name="basePackage" value="com.lilith.mapper"></property>
    </bean>
</beans>

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">

    <!--Spring-->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:application.xml</param-value>
    </context-param>

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <!--DispatchServlet-->
    <servlet>
        <servlet-name>dispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>0</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>dispatcherServlet</servlet-name>
        <!--"/" 代表拦截所有请求,/*拦截所有请求包括jsp页面这些请求-->
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <!--解决POST请求中文乱码问题-->
    <filter>
        <filter-name>characterFilter</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>characterFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!--Rest支持-->
    <filter>
        <filter-name>hiddenHttpMethodFilter</filter-name>
        <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>hiddenHttpMethodFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

</web-app>

在ItemMapper中新增insert和selectById两个方法

public interface ItemMapper {

    void insert(Item item);
    Item selectById(Integer id);
}

在ItemMapper XML文件中增加对应的SQL语句，在mapper标签下新增以下内容

<sql id="itemColumsWithoutId">
    name,price,pic,create_time,detail
</sql>

<sql id="itemColums">
    id,name,price,pic,create_time,detail
</sql>

<insert id="insert" useGeneratedKeys="true" keyColumn="id" keyProperty="id">
    INSERT item
    (<include refid="itemColumsWithoutId" />)
    VALUES (#{name},#{price},#{pic},#{createTime},#{detail})
</insert>

<select id="selectById" resultType="com.lilith.entity.Item">
    SELECT
    <include refid="itemColums"></include>
    FROM item
    WHERE id=#{id}
</select>

增加ItemMapperTest测试类，对方法进行测试

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:application.xml")
public class ItemMapperTest {

    @Autowired
    private ItemMapper itemMapper;

    @Test
    public void insert() {
        for (int i = 10; i < 20; i++) {
            Item item = new Item();
            item.setName("Mark " + i);
            item.setPrice(12.0);
            item.setDetail("IRON MAN ARMY");
            item.setCreateTime(new Date());

            itemMapper.insert(item);
        }
    }

    @Test
    public void selectById() {

        Item item = itemMapper.selectById(18);
        System.out.println("查询到的数据为：" + item);
    }
}

测试insert方法

测试selectById方法

新增ItemService接口及实现类

public interface ItemService {

    void save(Item item);

    Item findById(Integer id);
}

@Service
public class ItemServiceImpl implements ItemService {

    @Autowired
    private ItemMapper itemMapper;

    @Override
    public void save(Item item) {
        itemMapper.insert(item);
    }

    @Override
    public Item findById(Integer id) {
        return itemMapper.selectById(id);
    }
}

service层配置切面和事务通知，在application.xml中增加配置

<!--配置事务通知-->
<tx:advice id="advice" transaction-manager="dataSourceTransactionManager">
    <tx:attributes>
        <tx:method name="save*" propagation="REQUIRED"/>
        <tx:method name="update*" propagation="REQUIRED"/>
        <tx:method name="delete*" propagation="REQUIRED"/>
        <tx:method name="find*" read-only="true" />
        <tx:method name="*" propagation="REQUIRED"/>
    </tx:attributes>
</tx:advice>

<!--配置切面-->
<aop:config>
    <aop:pointcut id="pointcut" expression="execution(* com.lilith.service.impl.*.*(..))"/>
    <aop:advisor advice-ref="advice" pointcut-ref="pointcut" />
</aop:config>

生成ItemServiceTest测试类

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:application.xml")
public class ItemServiceTest {

    @Autowired
    private ItemService itemService;

    @Test
    public void save() {
        Item item = new Item();
        item.setName("电脑");
        item.setPrice(9999.0);
        item.setCreateTime(new Date());

        itemService.save(item);
    }

    @Test
    public void findById() {

        Item item = itemService.findById(20);
        System.out.println("itemService查询到的数据为：" + item);
    }
}

测试save方法

测试findById方法

编写ItemController

@Controller
@RequestMapping("/item")
public class ItemController {

    @Autowired
    private ItemService itemService;

    @GetMapping("/{id}")
    public String getItem(@PathVariable("id") Integer id, Model model){
        Item item = itemService.findById(id);
        model.addAttribute("item",item);
        return "item";
    }
}

在WEB-INF下创建pages文件夹，新增item.jsp页面

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/fmt"  prefix="fmt"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
</head>
<body>
<form>
    <table width="100%" border=1>
        <tr>
            <td>商品名称</td>
            <td> ${item.name } </td>
        </tr>
        <tr>
            <td>商品价格</td>
            <td> ${item.price } </td>
        </tr>
        <tr>
            <td>生成日期</td>
            <td> <fmt:formatDate value="${item.createTime}" pattern="yyyy-MM-dd HH:mm:ss"/> </td>
        </tr>
        <tr>
            <td>商品简介</td>
            <td>${item.detail} </td>
        </tr>
    </table>
</form>
</body>
</html>

在Project Structure的Artifacts目录下将右侧的jar包全部导入左侧的新建的lib目录下