一、整体概览
首先看maven工程的创建
二、各层的文件配置
2.1,SSM父工程
<span style="font-family:KaiTi_GB2312;font-size:18px;"><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>SSM-parent</groupId> <artifactId>Angel.SSM</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>pom</packaging> <!-- 集中定义依赖版本号 --> <properties> <junit.version>4.12</junit.version> <spring.version>4.1.3.RELEASE</spring.version> <mybatis.version>3.2.8</mybatis.version> <mybatis.spring.version>1.2.2</mybatis.spring.version> <mysql.version>5.1.32</mysql.version> <slf4j.version>1.6.4</slf4j.version> <jackson.version>2.4.2</jackson.version> <druid.version>1.0.9</druid.version> <jstl.version>1.2</jstl.version> <servlet-api.version>2.5</servlet-api.version> <jsp-api.version>2.0</jsp-api.version> <joda-time.version>2.5</joda-time.version> <commons-lang3.version>3.3.2</commons-lang3.version> <commons-io.version>1.3.2</commons-io.version> <commons-net.version>3.3</commons-net.version> <jsqlparser.version>0.9.1</jsqlparser.version> <commons-fileupload.version>1.3.1</commons-fileupload.version> </properties> <dependencyManagement> <dependencies> <!-- 时间操作组件 --> <dependency> <groupId>joda-time</groupId> <artifactId>joda-time</artifactId> <version>${joda-time.version}</version> </dependency> <!-- Apache工具组件 --> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-lang3</artifactId> <version>${commons-lang3.version}</version> </dependency> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-io</artifactId> <version>${commons-io.version}</version> </dependency> <dependency> <groupId>commons-net</groupId> <artifactId>commons-net</artifactId> <version>${commons-net.version}</version> </dependency> <!-- Jackson Json处理工具包 --> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>${jackson.version}</version> </dependency> <!-- 单元测试 --> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>${junit.version}</version> <scope>test</scope> </dependency> <!-- 日志处理 --> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>${slf4j.version}</version> </dependency> <!-- Mybatis --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>${mybatis.version}</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>${mybatis.spring.version}</version> </dependency> <!-- MySql --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>${mysql.version}</version> </dependency> <!-- 连接池 --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>${druid.version}</version> </dependency> <!-- Spring --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aspects</artifactId> <version>${spring.version}</version> </dependency> <!-- JSP相关 --> <dependency> <groupId>jstl</groupId> <artifactId>jstl</artifactId> <version>${jstl.version}</version> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> <version>${servlet-api.version}</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>jsp-api</artifactId> <version>${jsp-api.version}</version> <scope>provided</scope> </dependency> </dependencies> </dependencyManagement> <build> <finalName>${project.artifactId}</finalName> <plugins> <!-- 资源文件拷贝插件 --> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-resources-plugin</artifactId> <version>2.7</version> <configuration> <encoding>UTF-8</encoding> </configuration> </plugin> <!-- java编译插件 --> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.2</version> <configuration> <source>1.7</source> <target>1.7</target> <encoding>UTF-8</encoding> </configuration> </plugin> </plugins> <pluginManagement> <plugins> <!-- 配置Tomcat插件 --> <plugin> <groupId>org.apache.tomcat.maven</groupId> <artifactId>tomcat7-maven-plugin</artifactId> <version>2.2</version> </plugin> </plugins> </pluginManagement> </build> <modules> <module>Angel-pojo</module> <module>Angel-mapper</module> <module>Angel-service</module> <module>Angel-web</module> </modules> </project></span>
2.2,pojo不依赖任何jar包,略过
2.3,mapper
<span style="font-family:KaiTi_GB2312;font-size:18px;"><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>SSM-parent</groupId> <artifactId>Angel.SSM</artifactId> <version>0.0.1-SNAPSHOT</version> </parent> <artifactId>Angel-mapper</artifactId> <!-- 依赖管理 --> <dependencies> <dependency> <groupId>SSM-parent</groupId> <artifactId>Angel-pojo</artifactId> <version>0.0.1-SNAPSHOT</version> </dependency> <!-- Mybatis --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> </dependency> <!-- MySql --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <!-- 连接池 --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> </dependency> </dependencies> <!-- 如果不添加此节点Mybatis的mapper.xml文件都会被漏掉 --> <build> <resources> <resource> <directory>src/main/java</directory> <includes> <include>**/*.properties</include> <include>**/*.xml</include> </includes> <filtering>false</filtering> </resource> </resources> </build> </project></span>
2.4,service
<span style="font-family:KaiTi_GB2312;font-size:18px;"><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>SSM-parent</groupId> <artifactId>Angel.SSM</artifactId> <version>0.0.1-SNAPSHOT</version> </parent> <artifactId>Angel-service</artifactId> <!-- 依赖管理 --> <dependencies> <dependency> <groupId>SSM-parent</groupId> <artifactId>Angel-mapper</artifactId> <version>0.0.1-SNAPSHOT</version> </dependency> <!-- Spring --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aspects</artifactId> </dependency> </dependencies> </project></span>
2.5,Web
<span style="font-family:KaiTi_GB2312;font-size:18px;"><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>SSM-parent</groupId> <artifactId>Angel.SSM</artifactId> <version>0.0.1-SNAPSHOT</version> </parent> <artifactId>Angel-web</artifactId> <packaging>war</packaging> <!-- 依赖管理 --> <dependencies> <dependency> <groupId>SSM-parent</groupId> <artifactId>Angel-service</artifactId> <version>0.0.1-SNAPSHOT</version> </dependency> <!-- JSP相关 --> <dependency> <groupId>jstl</groupId> <artifactId>jstl</artifactId> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>jsp-api</artifactId> <scope>provided</scope> </dependency> <!-- Jackson Json处理工具包 --> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> </dependency> </dependencies> </project></span>
2.5.2,spring整合配置文件
2.5.2.1,Mybatis
目前无,当使用到分页插件,或者额外的功能配置时,需要进行配置,下面以配置分页插件为例:
<span style="font-family:KaiTi_GB2312;font-size:18px;"><?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis3 config.dtd"> <configuration> <!-- 配置分页插件 --> <plugins> <plugin interceptor="com.github.pagehelper.PageHelper"> <!-- 设置数据库类型Oracle,MySQL,MarinDBName,SQLite,PostareSQL六种数据库 --> <property name="dialect" value="mysql"/> </plugin> </plugins> </configuration></span>
jdbc.properties:数据库连接信息配置,主要包括jdbc.driver数据库驱动;jdbc.url数据库连接地址;jdbc.username连接用户名称;jdbc.password用户密码
2.5.2.2,spring配置
(为了分层解耦,为每一层,每一个用途的spring配置,都进行了单独配置)
1,首先:applicationContext-dao.xml,在这一层,主要配置数据库连接池(用到jdbc.properties数据库连接信息),Mybatis配置信息,加载Mybatis的mapper对象
<span style="font-family:KaiTi_GB2312;font-size:18px;"><beans xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" 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-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd"> <!-- 数据库连接池 --> <!-- 加载配置文件 --> <context:property-placeholder location="classpath:resource/*.properties" /> <!-- 数据库连接池 --> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close"> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <property name="driverClassName" value="${jdbc.driver}" /> <property name="maxActive" value="10" /> <property name="minIdle" value="5" /> </bean> <!-- 让spring管理sqlsessionfactory--> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 数据库连接池 --> <property name="dataSource" ref="dataSource" /> <!-- 加载mybatis的全局配置文件 --> <property name="configLocation" value="classpath:mybatis/SqlMapConfig.xml" /> </bean> <!-- 配置扫描包,加载mapper代理对象 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="Angel.mapper" /> </bean> </beans></span>
2,applicationContext-service.xml,主要就是配置扫描包,一句话:
<span style="font-family:KaiTi_GB2312;font-size:18px;"><!-- 扫描包,加载service实现类 --> <context:component-scan base-package="Angel.service"></context:component-scan> </span>
3,applicationContext-trans.xml事务传播配置,AOP切面配置
<span style="font-family:KaiTi_GB2312;font-size:18px;"><beans xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" 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-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd"> <!-- 事务管理器 --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <!-- 数据源 --> <property name="dataSource" ref="dataSource" /> </bean> <!-- 通知 --> <tx:advice id="txAdvice" transaction-manager="transactionManager"> <tx:attributes> <!-- 传播行为 --> <tx:method name="save*" propagation="REQUIRED" /> <tx:method name="insert*" propagation="REQUIRED" /> <tx:method name="add*" propagation="REQUIRED" /> <tx:method name="create*" propagation="REQUIRED" /> <tx:method name="delete*" propagation="REQUIRED" /> <tx:method name="update*" propagation="REQUIRED" /> <tx:method name="find*" propagation="SUPPORTS" read-only="true" /> <tx:method name="select*" propagation="SUPPORTS" read-only="true" /> <tx:method name="get*" propagation="SUPPORTS" read-only="true" /> </tx:attributes> </tx:advice> <!-- 切面 --> <aop:config> <aop:advisor advice-ref="txAdvice" pointcut="execution(* Angel.service.*.*(..))" /> </aop:config> </beans> </span>
2.5.2.3,springMVC配置
<span style="font-family:KaiTi_GB2312;font-size:18px;"><?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:p="http://www.springframework.org/schema/p" 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/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <context:component-scan base-package="Angel.controller" /> <mvc:annotation-driven /> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/"></property> <property name="suffix" value=".jsp" /> </bean> <!-- 资源映射 --> <mvc:resources location="/WEB-INF/css/" mapping="/css/**" /> <mvc:resources location="/WEB-INF/js/" mapping="/js/**" /> <!-- 当有文件上传需要时,定义文件上传解析器,在同时,也需要在pom文件中添加上传jar的依赖 --> <!--<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!-- 设定默认编码 --> <property name="defaultEncoding" value="UTF-8"></property> <!-- 设定文件上传的最大值5MB,5*1024*1024 --> <property name="maxUploadSize" value="5242880"></property> </bean>--> </beans> </span>
2.5.2.4,web.xml配置
主要包括,SpringMVC前端控制器的启动,spring容器的启动配置,post乱码过滤
<span style="font-family:KaiTi_GB2312;font-size:18px;"><?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5"> <display-name>Angel-web</display-name> <welcome-file-list> <welcome-file>/WEB-INF/jsp/index.jsp</welcome-file> </welcome-file-list> <!-- 加载spring容器 --> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring/applicationContext-*.xml</param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <!-- 解决post乱码过滤器 --> <filter> <filter-name>CharacterEncodingFilter</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>CharacterEncodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <!-- springmvc的前端控制器 --> <servlet> <servlet-name>Angel-web</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring/springmvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>Angel-web</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app></span>
三、具体实例
3.1,pojo实例类
TbUser.java(篇幅所限,set和get方法略去)
<span style="font-family:KaiTi_GB2312;font-size:18px;">package Angel.pojo; import java.util.Date; public class TbUser { private Long id; private String username; private String password; private String phone; private String email; private Date created; private Date updated;</span>
3.2,mapper
3.2.1,mapper接口类TbUserMapper.java
<span style="font-family:KaiTi_GB2312;font-size:18px;">package Angel.mapper; import Angel.pojo.TbUser; public interface TbUserMapper { TbUser selectByName(String Name); }</span>
3.2.2,sql实现文件TbUserMapper.xml
<span style="font-family:KaiTi_GB2312;font-size:18px;"></pre><pre name="code" class="html"><?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="Angel.mapper.TbUserMapper" > <resultMap id="BaseResultMap" type="Angel.pojo.TbUser" > <id column="id" property="id" jdbcType="BIGINT" /> <result column="username" property="username" jdbcType="VARCHAR" /> <result column="password" property="password" jdbcType="VARCHAR" /> <result column="phone" property="phone" jdbcType="VARCHAR" /> <result column="email" property="email" jdbcType="VARCHAR" /> <result column="created" property="created" jdbcType="TIMESTAMP" /> <result column="updated" property="updated" jdbcType="TIMESTAMP" /> </resultMap> <select id="selectByName" resultMap="BaseResultMap" parameterType="java.lang.String" > select id, username, password,phone, email, created, updated from tb_user where username = #{username,jdbcType=VARCHAR} </select> </mapper></span>
3.3,service
UserServiceImpl.java(接口省略)
<span style="font-family:KaiTi_GB2312;font-size:18px;">package Angel.service.impl; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import Angel.mapper.TbUserMapper; import Angel.pojo.TbUser; import Angel.service.UserService; @Service(value="userService") public class UserServiceImpl implements UserService { @Autowired private TbUserMapper userMapper; @Override public TbUser selectByName(String Name) { return userMapper.selectByName(Name); } } </span>
3.4,web-UserController.java
<span style="font-family:KaiTi_GB2312;font-size:18px;">package Angel.controller; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.http.HttpServletResponse; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import Angel.pojo.TbUser; import Angel.service.UserService; import com.fasterxml.jackson.databind.ObjectMapper; @Controller public class UserController { @Autowired private UserService userService; @RequestMapping("/user/find/{name}") public void insertUser(@PathVariable("name") String name,HttpServletResponse response) throws IOException { TbUser user=userService.selectByName(name); ObjectMapper objectMapper=new ObjectMapper(); response.setContentType("application/json;charset=UTF-8"); String json=""; PrintWriter out=response.getWriter(); if(user!=null){ json=objectMapper.writeValueAsString(user); out.write(json); }else{ out.write("error"); } } }</span>
3.5,JSP页面
<span style="font-family:KaiTi_GB2312;font-size:18px;"><%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme() + "://"+ request.getServerName() + ":" + request.getServerPort()+ path + "/"; %> <!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>SSM-Angel</title> <link rel="stylesheet" type="text/css" href="js/jquery-easyui-1.4.1/themes/default/easyui.css" /> <link rel="stylesheet" type="text/css" href="js/jquery-easyui-1.4.1/themes/icon.css" /> </head> <body> <input type="text" id="username"/><br><br> <span id="detail"></span><br><br> <input type="button" id="" value="查询" onclick="findUser()"/> <script type="text/javascript" src="js/jquery-easyui-1.4.1/jquery.min.js"></script> <script type="text/javascript" src="js/jquery-easyui-1.4.1/jquery.easyui.min.js"></script> <script type="text/javascript" src="js/jquery-easyui-1.4.1/locale/easyui-lang-zh_CN.js"></script> <script type="text/javascript"> function findUser(){ var username=$("#username").val(); $.post('<%=basePath%>user/find/'+username,function(data){ //测试框架效果,输入的用户,在数据库中存在相应数据,因此未做判空处理 if(data!="error"){ var detailInfo="username:"+data.username+" phone:"+data.phone+" ..."; $("#detail").text(detailInfo); }else{ $.messager.alert("info","查询用户出错!") } }); } </script> </body> </html> </span>
3.6,运行结果截图
四、总结
虽然用maven减少了jar下载引用的负担,但是,从SSM框架的搭建可以看出,引入了特别多的依赖,而且,当我在父工程进行引用后,在各个子模块需要用到的时候,还需要再次依赖引用,有什么方法可以解决这种依赖引用呢,接下来介绍spring boot