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[Java教程]第三章 Java框架整合


1、业务模块与数据模块分离

在实际开发中,我们项目的架构业务模块和数据模块是分离的,举个例子,假设我们的项目有"人员管理模块"和"酒店管理模块"两个模块,按照上一章的介绍,我们会建立下图所示的项目结构:

其中,人员管理模块的controller、service、dao、mapper都在一个项目中,而在实际使用中,我们会将数据模块分离出来,即将以上两个子模块的service、dao、mapper拿出来,放在一个子项目中,形成如下的项目结构:

注意以下几点:

  • 包的命名最好是com.xxx.mapper.user和不是com.xxx.user.mapper,前者在spring.
  • 在controller那一层的项目是需要部署的,即是war,而下边的数据模块是作为war的一个jar,所以在war层的pom.
  • service层到底是放在业务模块处还是放在数据模块处,这个根据需求而定,一般而言,都放在数据模块处,方便彼此service的调用,如userService调用hotelService,如果这个时候把两个service分别放在各自的业务模块层中,相互的调用就要通过RPC了,当然,有的时候可能有些与其他模块都不调用的service放在war层可能会好一些。
  • 将来编写的缓存模块类、通用模块类、RPC工具类等都会作为jar被war层调用。

 

2、实现

我将上一章的项目做了修改,将ssmm项目改成了userManagement项目,并将userManagement项目实现了业务模块和数据模块的分离,具体的操作参照第一章和第二章的相关内容,这里直接给出项目结构和各个文件。

2.1、项目结构

2.2、代码实现

2.2.1、ssmm0

pom.

 1 <??> 2 <project ="http://maven.apache.org/POM/4.0.0" ="http://www.w3.org/2001/ 3   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> 4  5   <modelVersion>4.0.0</modelVersion> 6  7   <groupId>com.xxx</groupId> 8   <artifactId>ssmm0</artifactId> 9   <version>1.0-SNAPSHOT</version> 10  11   <name>ssmm0</name> 12   <packaging>pom</packaging><!-- 父模块 --> 13  14   <!-- 管理子模块 --> 15   <modules> 16     <module>userManagement</module><!-- 具体业务1-人员管理系统 --> 17     <module>data</module><!-- 封装数据操作 --> 18   </modules> 19  20   <properties> 21     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> 22     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> 23   </properties> 24  25   <!-- dependencyManagement不会引入实际的依赖,只是作为一个依赖池,供其和其子类使用 --> 26   <dependencyManagement> 27     <dependencies> 28       <!-- json --> 29       <dependency> 30         <groupId>com.alibaba</groupId> 31         <artifactId>fastjson</artifactId> 32         <version>1.1.39</version> 33       </dependency> 34       <!-- servlet --> 35       <dependency> 36         <groupId>javax.servlet</groupId> 37         <artifactId>javax.servlet-api</artifactId> 38         <version>3.0.1</version> 39         <scope>provided</scope> 40       </dependency> 41       <!-- spring --> 42       <dependency> 43         <groupId>org.springframework</groupId> 44         <artifactId>spring-core</artifactId> 45         <version>3.2.6.RELEASE</version> 46       </dependency> 47       <dependency> 48         <groupId>org.springframework</groupId> 49         <artifactId>spring-beans</artifactId> 50         <version>3.2.6.RELEASE</version> 51       </dependency> 52       <dependency> 53         <groupId>org.springframework</groupId> 54         <artifactId>spring-context</artifactId> 55         <version>3.2.6.RELEASE</version> 56       </dependency> 57       <dependency> 58         <groupId>org.springframework</groupId> 59         <artifactId>spring-web</artifactId> 60         <version>3.2.6.RELEASE</version> 61       </dependency> 62       <dependency> 63         <groupId>org.springframework</groupId> 64         <artifactId>spring-webmvc</artifactId> 65         <version>3.2.6.RELEASE</version> 66       </dependency> 67       <!-- 这个是使用velocity的必备包 --> 68       <dependency> 69         <groupId>org.springframework</groupId> 70         <artifactId>spring-context-support</artifactId> 71         <version>3.2.6.RELEASE</version> 72       </dependency> 73       <!-- mysql --> 74       <dependency> 75         <groupId>mysql</groupId> 76         <artifactId>mysql-connector-java</artifactId> 77         <version>5.1.27</version> 78         <scope>runtime</scope> 79       </dependency> 80       <!-- 数据源 --> 81       <dependency> 82         <groupId>org.apache.tomcat</groupId> 83         <artifactId>tomcat-jdbc</artifactId> 84         <version>7.0.47</version> 85       </dependency> 86       <!-- mybatis --> 87       <dependency> 88         <groupId>org.mybatis</groupId> 89         <artifactId>mybatis</artifactId> 90         <version>3.1.1</version> 91       </dependency> 92       <dependency> 93         <groupId>org.mybatis</groupId> 94         <artifactId>mybatis-spring</artifactId> 95         <version>1.1.1</version> 96       </dependency> 97       <!-- velocity --> 98       <dependency> 99         <groupId>org.apache.velocity</groupId>100         <artifactId>velocity</artifactId>101         <version>1.5</version>102       </dependency>103       <dependency>104         <groupId>velocity-tools</groupId>105         <artifactId>velocity-tools-generic</artifactId>106         <version>1.2</version>107       </dependency>108       <!-- 用于加解密 -->109       <dependency>110         <groupId>commons-codec</groupId>111         <artifactId>commons-codec</artifactId>112         <version>1.7</version>113       </dependency>114       <dependency>115         <groupId>org.bouncycastle</groupId>116         <artifactId>bcprov-jdk15on</artifactId>117         <version>1.47</version>118       </dependency>119       <!-- 集合工具类 -->120       <dependency>121         <groupId>org.apache.commons</groupId>122         <artifactId>commons-collections4</artifactId>123         <version>4.0</version>124       </dependency>125       <!-- http -->126       <dependency>127         <groupId>org.apache.httpcomponents</groupId>128         <artifactId>httpclient</artifactId>129         <version>4.2.6</version>130       </dependency>131     </dependencies>132   </dependencyManagement>133   134   <!-- 引入实际依赖 -->135   <dependencies>136     <!-- json -->137     <dependency>138       <groupId>com.alibaba</groupId>139       <artifactId>fastjson</artifactId>140     </dependency>141     <!-- spring -->142     <dependency>143       <groupId>org.springframework</groupId>144       <artifactId>spring-core</artifactId>145     </dependency>146     <dependency>147       <groupId>org.springframework</groupId>148       <artifactId>spring-beans</artifactId>149     </dependency>150     <dependency>151       <groupId>org.springframework</groupId>152       <artifactId>spring-context</artifactId>153     </dependency>154     <!-- 集合工具类 -->155     <dependency>156       <groupId>org.apache.commons</groupId>157       <artifactId>commons-collections4</artifactId>158     </dependency>159   </dependencies>160   161   <build>162     <resources>163       <!-- 164         这里配置了这一块儿true,才可以让指定文件(这里是src/main/resources/*.165         值得注意的是,如果src/main/resources下还有其他文件,而你不想让其读pom.166         你还必须得把src/main/resources下的其余文件再配置一遍,配置为false(不可读pom.167         如下边的注释那样,否则,会报这些文件(在这里,就是*.properties)找不到的错误168       -->169       <resource>170         <directory>src/main/resources</directory>171         <filtering>true</filtering>172         <includes>173           <include>*.</include>174         </includes>175       </resource>176       <!-- <resource>177         <directory>src/main/resources</directory>178         <filtering>false</filtering>可以读 ,若改为false就是不可读179         <includes>180           <include>*.properties</include>181         </includes>182       </resource> -->183     </resources>184   </build>185   186   <!-- 187     profiles可以定义多个profile,然后每个profile对应不同的激活条件和配置信息,从而达到不同环境使用不同配置信息的效果 188     注意两点:189     1)<activeByDefault>true</activeByDefault>这种情况表示服务器启动的时候就采用这一套env(在这里,就是prod)190     2)当我们启动服务器后,想采用开发模式,需切换maven的env为dev,如果env的配置本身就是dev,需要将env换成rc或prod,点击apply,然后再将env切换成dev,点击apply才行191   -->192   <profiles>193     <!-- 开发env -->194     <profile>195       <id>dev</id>196       <activation>197         <activeByDefault>false</activeByDefault>198         <property>199           <name>env</name>200           <value>dev</value>201         </property>202       </activation>203       <properties>204         <env>dev</env>205 206         <jdbc.driverClassName>com.mysql.jdbc.Driver</jdbc.driverClassName>207         <!-- 208           对于jdbc.url中内容的配置,如果需要配置 &amp;时,有两种方法:209           1)如下边这样,使用<![CDATA[XXX]]>包起来210           2)使用jdbc.properties文件来读取此pom.211           显然,前者更方便,而且还省了一个jdbc.properties的文件,但是,有的时候,还是会用后者的;212           在使用后者的时候,注意三点:213           1)需要修改上边的build中的内容214           2)需要在spring.215           3)jdbc.properties与spring.216         -->217         <jdbc.url><![CDATA[jdbc:mysql://127.0.0.1:3306/blog?zeroDateTimeBehavior=convertToNull&amp;useUnicode=true&amp;characterEncoding=utf-8]]></jdbc.url>218         <jdbc.username>root</jdbc.username>219         <jdbc.password>123456</jdbc.password>220       </properties>221     </profile>222     <!-- 预上线env -->223     <profile>224       <id>rc</id>225       <activation>226         <activeByDefault>false</activeByDefault>227         <property>228           <name>env</name>229           <value>rc</value>230         </property>231       </activation>232       <properties>233         <env>rc</env>234 235         <jdbc.driverClassName>com.mysql.jdbc.Driver</jdbc.driverClassName>236         <!-- 假设的一个地址 -->237         <jdbc.url><![CDATA[jdbc:mysql://10.10.10.100:3306/blog?zeroDateTimeBehavior=convertToNull&amp;useUnicode=true&amp;characterEncoding=utf-8]]></jdbc.url>238         <jdbc.username>root2</jdbc.username>239         <jdbc.password>1234562</jdbc.password>240       </properties>241     </profile>242     <!-- 线上env -->243     <profile>244       <id>prod</id>245       <activation>246         <activeByDefault>true</activeByDefault>247         <property>248           <name>env</name>249           <value>prod</value>250         </property>251       </activation>252       <properties>253         <env>prod</env>254         255         <jdbc.driverClassName>com.mysql.jdbc.Driver</jdbc.driverClassName>256         <!-- 假设的一个地址 -->257         <jdbc.url><![CDATA[jdbc:mysql://99.99.99.999:3307/blog?zeroDateTimeBehavior=convertToNull&amp;useUnicode=true&amp;characterEncoding=utf-8]]></jdbc.url>258         <jdbc.username>sadhijhqwui</jdbc.username>259         <jdbc.password>zxczkchwihcznk=</jdbc.password>260       </properties>261     </profile>262   </profiles>263 </project>

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注意:

  • 所有的注意点:都在注释中
  • 上述<build>中的resource的配置是为了是spring.

  • profiles的配置是为了配置多套环境(在这里配置了三套env,开发,预上线和线上环境),具体的注意点,查看注释

2.2.2、ssmm0-data

pom.

<??><project ="http://maven.apache.org/POM/4.0.0" ="http://www.w3.org/2001/  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">  <modelVersion>4.0.0</modelVersion>  <!-- 指定父模块 -->  <parent>    <groupId>com.xxx</groupId>    <artifactId>ssmm0</artifactId>    <version>1.0-SNAPSHOT</version>  </parent>    <groupId>com.xxx.ssmm0</groupId>  <artifactId>ssmm0-data</artifactId>  <name>ssmm0-data</name>  <packaging>jar</packaging><!-- 只是作为其他模块使用的工具 -->  <!-- 引入实际依赖 -->  <dependencies>    <!-- mysql -->    <dependency>      <groupId>mysql</groupId>      <artifactId>mysql-connector-java</artifactId>    </dependency>    <!-- 数据源 -->    <dependency>      <groupId>org.apache.tomcat</groupId>      <artifactId>tomcat-jdbc</artifactId>    </dependency>    <!-- mybatis -->    <dependency>      <groupId>org.mybatis</groupId>      <artifactId>mybatis</artifactId>    </dependency>    <dependency>      <groupId>org.mybatis</groupId>      <artifactId>mybatis-spring</artifactId>    </dependency>  </dependencies></project>

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注意:<package>为jar

com.xxx.model.userManagement.Admin

package com.xxx.model.userManagement;/** * 管理员 */public class Admin {  private int id;  private String username;  private String password;  public int getId() {    return id;  }  public void setId(int id) {    this.id = id;  }  public String getUsername() {    return username;  }  public void setUsername(String username) {    this.username = username;  }  public String getPassword() {    return password;  }  public void setPassword(String password) {    this.password = password;  }}

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com.xxx.mapper.userManagement.AdminMapper

package com.xxx.mapper.userManagement;import org.apache.ibatis.annotations.Insert;import org.apache.ibatis.annotations.Param;import org.apache.ibatis.annotations.Result;import org.apache.ibatis.annotations.Results;import org.apache.ibatis.annotations.Select;import com.xxx.model.userManagement.Admin;/** * 管理员Mapper */public interface AdminMapper {  @Insert("INSERT INTO userinfo(username, password) VALUES(#{username},#{password})")  public int insertAdmin(Admin admin);  @Select("SELECT * FROM userinfo WHERE username = #{username} AND password = #{password}")  @Results(value = {       @Result(id = true, column = "id", property = "id"),      @Result(column = "username", property = "username"),      @Result(column = "password", property = "password") })  public Admin selectAdmin(@Param("username") String username,               @Param("password") String password);}

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com.xxx.dao.userManagement.AdminDao

package com.xxx.dao.userManagement;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Repository;import com.xxx.mapper.userManagement.AdminMapper;import com.xxx.model.userManagement.Admin;/** * 管理员DAO */@Repositorypublic class AdminDao {  @Autowired  private AdminMapper adminMapper;    public boolean register(Admin admin){    return adminMapper.insertAdmin(admin)==1?true:false;  }    public Admin login(String username ,String password){    return adminMapper.selectAdmin(username, password);  }}

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com.xxx.service.userManagement.AdminService

package com.xxx.service.userManagement;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import com.xxx.dao.userManagement.AdminDao;import com.xxx.model.userManagement.Admin;/** * 管理员service */@Servicepublic class AdminService {  @Autowired  private AdminDao adminDao;    public boolean register(Admin admin){    return adminDao.register(admin);  }    public Admin login(String username, String password) {    return adminDao.login(username, password);  }}

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代码很简单,与之前的基本一样,只是名字换了而已。

值得注意的是包名:com.xxx.mapper.userManagement而非com.xxx.userManagement.mapper。

2.2.3、ssmm0-userManagement

pom.

 1 <??> 2 <project ="http://maven.apache.org/POM/4.0.0" ="http://www.w3.org/2001/ 3   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> 4  5   <modelVersion>4.0.0</modelVersion> 6  7   <!-- 指定父模块 --> 8   <parent> 9     <groupId>com.xxx</groupId>10     <artifactId>ssmm0</artifactId>11     <version>1.0-SNAPSHOT</version>12   </parent>13   14   <groupId>com.xxx.ssmm0</groupId>15   <artifactId>ssmm0-userManagement</artifactId>16   <!--<version>1.0-SNAPSHOT</version>--><!-- 父模块已经指定了版本号,这里就不用了-->17 18   <name>ssmm0-userManagement</name>19   <packaging>war</packaging><!-- 需要部署的模块 -->20 21   <!-- 引入实际依赖 -->22   <dependencies>23     <!-- 将ssmm0-data项目作为一个jar引入项目中 -->24     <dependency>25       <groupId>com.xxx.ssmm0</groupId>26       <artifactId>ssmm0-data</artifactId>27       <version>1.0-SNAPSHOT</version>28     </dependency>29     <!-- servlet -->30     <dependency>31       <groupId>javax.servlet</groupId>32       <artifactId>javax.servlet-api</artifactId>33     </dependency>34     <!-- spring mvc -->35     <dependency>36       <groupId>org.springframework</groupId>37       <artifactId>spring-web</artifactId>38     </dependency>39     <dependency>40       <groupId>org.springframework</groupId>41       <artifactId>spring-webmvc</artifactId>42     </dependency>43     <!-- 这个是使用velocity的必备包 -->44     <dependency>45       <groupId>org.springframework</groupId>46       <artifactId>spring-context-support</artifactId>47     </dependency>48     <!-- velocity -->49     <dependency>50       <groupId>org.apache.velocity</groupId>51       <artifactId>velocity</artifactId>52     </dependency>53     <dependency>54       <groupId>velocity-tools</groupId>55       <artifactId>velocity-tools-generic</artifactId>56     </dependency>57   </dependencies>58 </project>

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注意:将ssmm0-data作为普通的jar引入即可。

spring.

 1 <??> 2 <beans ="http://www.springframework.org/schema/beans" 3   ="http://www.w3.org/2001/ ="http://www.springframework.org/schema/context" 4   ="http://www.springframework.org/schema/mvc" 5   xsi:schemaLocation="http://www.springframework.org/schema/beans  6               http://www.springframework.org/schema/beans/spring-beans-3.2.xsd 7               http://www.springframework.org/schema/context  8               http://www.springframework.org/schema/context/spring-context-3.2.xsd 9               http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">10              11   <!-- 注解扫描 -->12   <context:component-scan base-package="com.xxx" />13   14   <!-- 配置fastjson转换器 -->15   <mvc:annotation-driven>16     <mvc:message-converters register-defaults="true">17       <bean class="com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter"></bean>18     </mvc:message-converters>19   </mvc:annotation-driven>20   21   <!-- 引入数据源,这里变量的读取都是从ssmm0的pom.-->22   <bean id="xxxDataSource" class="org.apache.tomcat.jdbc.pool.DataSource" destroy-method="close">23     <property name="driverClassName" value="${jdbc.driverClassName}" />24     <property name="url" value="${jdbc.url}" />25     <property name="username" value="${jdbc.username}" />26     <property name="password" value="${jdbc.password}" />27   </bean>28   29   <!-- 引入mybatis -->30   <bean id="xxxSqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">31     <property name="dataSource" ref="xxxDataSource" />32   </bean>33   <bean id="xxxMapperScannerConfigurer" class="org.mybatis.spring.mapper.MapperScannerConfigurer">34     <!-- 35       这里就是包名为什么就做com.xxx.mapper.user而非com.xxx.user.mapper,36       这样的话,比如说有两个项目com.xxx.mapper.user和com.xxx.mapper.hotel,value只需写作com.xxx.mapper即可37       否则,value就要写作com.xxx.user.mapper,com.xxx.hotel.mapper38     -->39     <property name="basePackage" value="com.xxx.mapper" />40     <property name="sqlSessionFactoryBeanName" value="xxxSqlSessionFactory" />41   </bean>42   43   <!-- 配置velocity -->44   <bean id="velocityConfigurer" class="org.springframework.web.servlet.view.velocity.VelocityConfigurer">45     <property name="resourceLoaderPath">46       <value>WEB-INF/templates/</value>47     </property>48     <property name="velocityProperties">49       <props>50         <prop key="input.encoding">UTF-8</prop>51         <prop key="output.encoding">UTF-8</prop>52       </props>53     </property>54   </bean>55   <bean id="viewResolver" class="org.springframework.web.servlet.view.velocity.VelocityViewResolver"> 56     <property name="suffix" value=".vm" /> 57     <property name="contentType" value="text/html;charset=utf-8" /> 58     <property name="dateToolAttribute" value="date"/>59     <property name="numberToolAttribute" value="number"/>60   </bean>61 </beans>

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注意:这里对包名的体现,由于直接使用spring.

web.

 1 <??> 2 <web-app version="2.5" ="http://java.sun.com/ 3   ="http://www.w3.org/2001/ 4   xsi:schemaLocation="http://java.sun.com/> 5  6   <servlet> 7     <servlet-name>dispatcherServlet</servlet-name> 8     <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> 9     <init-param>10       <param-name>contextConfigLocation</param-name>11       <param-value>classpath:spring.</param-value>12     </init-param>13     <load-on-startup>1</load-on-startup>14   </servlet>15   <servlet-mapping>16     <servlet-name>dispatcherServlet</servlet-name>17     <url-pattern>/</url-pattern>18   </servlet-mapping>19 20   <filter>21     <filter-name>encodingFilter</filter-name>22     <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>23     <init-param>24       <param-name>encoding</param-name>25       <param-value>UTF-8</param-value>26     </init-param>27     <init-param>28       <param-name>forceEncoding</param-name>29       <param-value>true</param-value>30     </init-param>31   </filter>32   <filter-mapping>33     <filter-name>encodingFilter</filter-name>34     <url-pattern>/*</url-pattern>35   </filter-mapping>36 37   <welcome-file-list>38     <welcome-file>/index.jsp</welcome-file>39   </welcome-file-list>40 </web-app>

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com.xxx.web.admin.AdminController

 1 package com.xxx.web.admin; 2  3 import org.springframework.beans.factory.annotation.Autowired; 4 import org.springframework.stereotype.Controller; 5 import org.springframework.web.bind.annotation.RequestMapping; 6 import org.springframework.web.bind.annotation.RequestParam; 7 import org.springframework.web.bind.annotation.ResponseBody; 8 import org.springframework.web.servlet.ModelAndView; 9 10 import com.xxx.model.userManagement.Admin;11 import com.xxx.service.userManagement.AdminService;12 13 /**14  * adminController15 */16 @Controller17 @RequestMapping("/admin")18 public class AdminController {19   20   @Autowired21   private AdminService adminService;22   23   /**24    * 管理员注册25   */26   @ResponseBody27   @RequestMapping("/register")28   public boolean register(@RequestParam("username") String username,29               @RequestParam("password") String password){30     Admin admin = new Admin();31     admin.setUsername(username);32     admin.setPassword(password);33     34     boolean isRegisterSuccess = adminService.register(admin);35     36     return isRegisterSuccess;37   }38   39   /**40    * 管理员登录41   */42   @RequestMapping("/login")43   public ModelAndView login(@RequestParam("username") String username,44                @RequestParam("password") String password){45     Admin admin = adminService.login(username, password);46     47     ModelAndView modelAndView = new ModelAndView();48     if(admin == null){49       modelAndView.addObject("message", "用户不存在或者密码错误!请重新输入");50       modelAndView.setViewName("error");51     }else{52       modelAndView.addObject("admin", admin);53       modelAndView.setViewName("userinfo");54     }55     56     return modelAndView;57   }58 }

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error.vm

 1 <!DOCTYPE html> 2 <html lang="zh-cn"> 3 <head> 4   <meta charset="UTF-8"> 5   <title>登录失败</title> 6 </head> 7 <body> 8   <div> 9     $message10   </div>11 </body>12 </html>

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userinfo.vm

 1 <!DOCTYPE html> 2 <html lang="zh-cn"> 3 <head> 4   <meta charset="UTF-8"> 5   <title>登录成功</title> 6 </head> 7 <body> 8   <div> 9     id:$admin.id10     username:$admin.username11     password:$admin.password12   </div>13 </body>14 </html>

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具体测试过程:

  • 直接运行jetty的话,会发现连不上数据库服务器99.99.99.999,这是因为默认启动服务器之后,我们使用的是prod的一套env,这套env中的数据库服务器是我自己乱写的:99.99.99.999
  • 这时候,在ssmm0-userManagement项目上右击-->"Build Path"-->"Configure Build Path"-->"Maven"-->修改env,如下图所示,这样就切换到了dev的env下,之后再运行jetty,如果依旧不行的话,就采用ssmm0的pom.

这样,一个基本上就是企业中开发常用的结构的项目就完成了,这个项目非常重要,一定自己试着去写一个,一定要仔细看其中的每一条注释。