三大框架SSH搭建web项目实例

向右看齐 2022-01-28 07:07 249阅读 0赞

> ###### 前言： ######
> 
>       本文主要介绍的是如何使用三大框架来搭建一个简易的web项目。这里的三大框架指的是**struts2**、**spring** 和 **hibernate**，以为是SpringMVC+Spring+Hibernate的童鞋请自觉绕行。  
>       由于本文作者水平有限，对SSH的掌握程度较低，作者结合自身的工作经验以及业余时间的摸爬滚打，终于将三大框架搭建好的web项目运行成功。作者希望读者在看完本文后有什么指教，欢迎在本文评论区进行留言，大家一起探讨，共同进步。

### 一、环境准备 ###

*  Eclipse
 *  JDK 1.7
 *  struts-2.5.20
 *  spring-framework-4.3.18.RELEASE（spring 4）
 *  hibernate-release-4.3.11.Final（hibernate 4）
 *  tomcat 6.0
 *  其他架包：  
    （1）log4j-core-2.11.1.jar  
    （2）mysql-connector-java-5.1.26-bin.jar  
    （3）aopalliance-1.0.jar  
    （4）aspectjrt-1.5.3.jar  
    （5）aspectjweaver-1.5.3.jar  
    （6）commons-dbcp-1.4.jar  
    （7）commons-pool-1.6.jar

> 三大框架的架包以及其他架包的下载方法可参考作者总结的另一篇文章：[三大框架相关架包下载方法][Link 1]。

### 二、搭建步骤 ###

1、创建web项目frameworkdemo，并依次导入三大框架必需架包。

>  *  三大框架不同版本所必需的架包可能不同，不过大体必需的架包是一样的。如果想根据本文搭建web项目并正常运行，最好严格按照文章所说的架包进行下载。
>  *  架包直接放到/WEB-INF/lib目录下。

<table> 
 <thead> 
  <tr> 
   <th>序号</th> 
   <th align="left">struts2 - 必需架包</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>1</td> 
   <td align="left">commons-fileupload-1.4.jar</td> 
  </tr> 
  <tr> 
   <td>2</td> 
   <td align="left">commons-lang3-3.8.1.jar</td> 
  </tr> 
  <tr> 
   <td>3</td> 
   <td align="left">freemarker-2.3.28.jar</td> 
  </tr> 
  <tr> 
   <td>4</td> 
   <td align="left">javassist-3.20.0-GA.jar</td> 
  </tr> 
  <tr> 
   <td>5</td> 
   <td align="left">log4j-api-2.11.1.jar</td> 
  </tr> 
  <tr> 
   <td>6</td> 
   <td align="left">ognl-3.1.21.jar</td> 
  </tr> 
  <tr> 
   <td>7</td> 
   <td align="left">struts2-core-2.5.20.jar</td> 
  </tr> 
  <tr> 
   <td>8</td> 
   <td align="left">struts2-spring-plugin-2.5.20.jar<code>spring整合struts2时必需的插件</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th>序号</th> 
   <th align="left">spring 4 - 必需架包（spring4中的所有架包）</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>1</td> 
   <td align="left">commons-logging-1.2.jar <code>从struts2中获取该架包</code></td> 
  </tr> 
  <tr> 
   <td>2</td> 
   <td align="left">spring-aop-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>3</td> 
   <td align="left">spring-aspects-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>4</td> 
   <td align="left">spring-beans-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>5</td> 
   <td align="left">spring-context-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>6</td> 
   <td align="left">spring-context-support-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>7</td> 
   <td align="left">spring-core-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>8</td> 
   <td align="left">spring-expression-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>9</td> 
   <td align="left">spring-instrument-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>10</td> 
   <td align="left">spring-instrument-tomcat-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>11</td> 
   <td align="left">spring-jdbc-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>12</td> 
   <td align="left">spring-jms-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>13</td> 
   <td align="left">spring-messaging-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>14</td> 
   <td align="left">spring-orm-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>15</td> 
   <td align="left">spring-oxm-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>16</td> 
   <td align="left">spring-test-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>17</td> 
   <td align="left">spring-tx-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>18</td> 
   <td align="left">spring-web-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>19</td> 
   <td align="left">spring-webmvc-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>20</td> 
   <td align="left">spring-webmvc-portlet-4.3.18.RELEASE.jar</td> 
  </tr> 
  <tr> 
   <td>21</td> 
   <td align="left">spring-websocket-4.3.18.RELEASE.jar</td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th>序号</th> 
   <th align="left">hibernate 4 - 必需架包+可选 <code>/lib/optional/目录下为可选架包</code></th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>1</td> 
   <td align="left">antlr-2.7.7.jar</td> 
  </tr> 
  <tr> 
   <td>2</td> 
   <td align="left">dom4j-1.6.1.jar</td> 
  </tr> 
  <tr> 
   <td>3</td> 
   <td align="left">hibernate-commons-annotations-4.0.5.Final.jar</td> 
  </tr> 
  <tr> 
   <td>4</td> 
   <td align="left">hibernate-core-4.3.11.Final.jar</td> 
  </tr> 
  <tr> 
   <td>5</td> 
   <td align="left">hibernate-jpa-2.1-api-1.0.0.Final.jar</td> 
  </tr> 
  <tr> 
   <td>6</td> 
   <td align="left">jandex-1.1.0.Final.jar</td> 
  </tr> 
  <tr> 
   <td>7</td> 
   <td align="left">javassist-3.18.1-GA.jar</td> 
  </tr> 
  <tr> 
   <td>8</td> 
   <td align="left">jboss-logging-3.1.3.GA.jar</td> 
  </tr> 
  <tr> 
   <td>9</td> 
   <td align="left">jboss-logging-annotations-1.2.0.Beta1.jar</td> 
  </tr> 
  <tr> 
   <td>10</td> 
   <td align="left">jboss-transaction-api_1.2_spec-1.0.0.Final.jar</td> 
  </tr> 
  <tr> 
   <td>11</td> 
   <td align="left">ehcache-core-2.4.3.jar&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<code>见/lib/optional/ehcache/</code></td> 
  </tr> 
  <tr> 
   <td>12</td> 
   <td align="left">hibernate-ehcache-4.3.11.Final.jar<code>见/lib/optional/ehcache/</code></td> 
  </tr> 
  <tr> 
   <td>13</td> 
   <td align="left">slf4j-api-1.6.1.jar&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<code>见/lib/optional/ehcache/</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th>序号</th> 
   <th align="left">其他架包 <code>到Maven资源库中下载</code></th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>1</td> 
   <td align="left">log4j-core-2.11.1.jar <code>日志要用到</code></td> 
  </tr> 
  <tr> 
   <td>2</td> 
   <td align="left">mysql-connector-java-5.1.26-bin.jar <code>mysql驱动包</code></td> 
  </tr> 
  <tr> 
   <td>3</td> 
   <td align="left">aopalliance-1.0.jar&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<code>aop配置事务时用</code></td> 
  </tr> 
  <tr> 
   <td>4</td> 
   <td align="left">aspectjrt-1.5.3.jar&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<code>aop配置事务时用</code></td> 
  </tr> 
  <tr> 
   <td>5</td> 
   <td align="left">aspectjweaver-1.5.3.jar <code>aop配置事务时用</code></td> 
  </tr> 
  <tr> 
   <td>6</td> 
   <td align="left">commons-dbcp-1.4.jar <code>使用jdbc.properties配置数据库时用</code></td> 
  </tr> 
  <tr> 
   <td>7</td> 
   <td align="left">commons-pool-1.6.jar&nbsp;&nbsp;<code>使用jdbc.properties配置数据库时用</code></td> 
  </tr> 
 </tbody> 
</table>

> 总共**49**个架包导入项目之后，会发现javassist-xx-GA.jar重复，可将`javassist-3.18.1-GA.jar`移除，最终只留下**48**个架包。

项目结构预览：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTMwMjA1OTM_size_16_color_FFFFFF_t_70]  
2、文件配置  
作者的思路是：先**spring**整合**hibernate**，再**spring**整合**struts2**。

（1）**Spring** 整合 **Hibernate**：

>  *  spring整合hibernate时，spring可以替换hibernate的`hibernate.cfg.xml`与`xxx.hbm.xml`配置文件。

*  web.xml  
    在web.xml文件中指定spring配置文件的位置

<context-param>
    		<param-name>contextConfigLocation</param-name>
    		<param-value>
            classpath:resources/applicationContext.xml
    		</param-value>
    	</context-param>
    	<listener>
    		
    		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    	</listener>

> `classpath:`表示的是类路径，即src目录下的包路径，为了方便管理，三大框架的配置文件均放在`/resources/`包下。

既然已经指定了spring配置文件的路径，那就跟着在`/resources/`包下创建`applicationContext.xml`。

*  applicationContext.xml

因为spring要配置的事项较多，为了方便管理，最好是通过import引入的方式分模块来管理。

*  applicationContext\_jdbc.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 http://www.springframework.org/schema/context/spring-context.xsd">
    	
    	
    	<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
    		<property name="driverClassName" value="${jdbc.driverClassName}" />
    		<property name="url" value="${jdbc.url}" />
    		<property name="username" value="${jdbc.username}" />
    		<property name="password" value="${jdbc.password}" />
    	</bean>
    	<context:property-placeholder location="classpath:resources/jdbc.properties" />
    
    	
    	<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
    		<property name="dataSource" ref="dataSource"></property>
    		<property name="packagesToScan">
    			<list>
    				
    				<value>com.demo.entity*</value>
    			</list>
    		</property>
    		
    		
    		<property name="hibernateProperties">
    			<props>
    				<prop key="hibernate.dialect">
    					org.hibernate.dialect.MySQLDialect
    				</prop>
    				<prop key="hibernate.show_sql">true</prop>
    				<prop key="hibernate.format_sql">true</prop>
    				<prop key="hibernate.hbm2ddl.auto">update</prop>
    			</props>
    		</property>
    	</bean>
    </beans>

>  *  配置`dataSource`时需要指定`jdbc.properties`文件，并且，需要用到 commons-dbcp-*.jar与 commons-pool-*.jar 这两个架包。
>  *  `packagesToScan`指定了hibernate映射的实体类中需要加注解，这就替代了映射文件.hbm.xml，加载时会自动扫描指定包中的所有实体类。

*  jdbc.properties

jdbc.driverClassName=com.mysql.jdbc.Driver
    jdbc.url=jdbc:mysql://localhost:3306/test
    jdbc.username=root
    jdbc.password=root

> 注意：不要有空格

*  Student.java

package com.demo.entity;
    
    import javax.persistence.Column;
    import javax.persistence.Entity;
    import javax.persistence.GeneratedValue;
    import javax.persistence.Id;
    import javax.persistence.Table;
    
    @Entity
    @Table(name = "student", catalog = "test")
    public class Student implements java.io.Serializable { 
    	private Integer id;
    	private String name;
    
    	/** default constructor */
    	public Student() { 
    	}
    
    	/** full constructor */
    	public Student(String name) { 
    		this.name = name;
    	}
    
    	// Property accessors
    	@Id
    	@GeneratedValue
    	@Column(name = "id", unique = true, nullable = false)
    	public Integer getId() { 
    		return this.id;
    	}
    
    	public void setId(Integer id) { 
    		this.id = id;
    	}
    
    	@Column(name = "name")
    	public String getName() { 
    		return this.name;
    	}
    
    	public void setName(String name) { 
    		this.name = name;
    	}
    
    }

> `Student.java`是通过`hibernateTools`工具映射生成的，建议使用MyEclipse自动生成hibernate映射的实体类，如何生成不在本文的考虑范围。

*  applicationContext-transaction.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:tx="http://www.springframework.org/schema/tx" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">
    	
    	
    	
    	<bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    		<property name="dataSource" ref="dataSource"></property>
    	</bean>
    
    	
    	<tx:advice id="txAdvice" transaction-manager="txManager">
    		<tx:attributes>
    			<tx:method name="add*" propagation="REQUIRED" />
    			<tx:method name="insert*" propagation="REQUIRED" />
    			<tx:method name="update*" propagation="REQUIRED" />
    			<tx:method name="delete*" propagation="REQUIRED" />
    			<tx:method name="select*" read-only="true" />
    			<tx:method name="find*" read-only="true" />
    			<tx:method name="get*" read-only="true" />
    			<tx:method name="query*" read-only="true" />
    		</tx:attributes>
    	</tx:advice>
    	
    	
    	<tx:annotation-driven transaction-manager="txManager" />
    	
    	
    	<aop:config proxy-target-class="true">
    		<aop:pointcut expression=" execution(* com.demo.service..*(..))" id="serviceMethod" />
    		<aop:advisor advice-ref="txAdvice" pointcut-ref="serviceMethod" />
    	</aop:config>
    </beans>

>  *  service开启事务后，service层的实现类上需要加一个注解：`@Transactional`;
>  *  使用到aop配置，需要用到三个架包：`aopalliance-1.0.jar`、`aspectjrt-1.5.3.jar`、`aspectjweaver-1.5.3.jar`；

后面的三个配置文件applicationContext\_action.xml、applicationContext\_service、applicationContext\_dao.xml比较简单了。

*  applicationContext\_action.xml

*  applicationContext\_service.xml

*  applicationContext\_dao.xml

然后就是把各层的类部署好：

*  SysException.java

package com.demo.exception;
    
    /** * 自定义异常，全局 */
    public class SysException extends Exception { 
    	private static final long serialVersionUID = 1L;
    	private String message;
    
    	public String getMessage() { 
    		return message;
    	}
    
    	public SysException(String message) { 
    		this.message = message;
    	}
    }

*  StudentAction.java

package com.demo.action;
    
    import java.io.PrintWriter;
    import java.io.StringWriter;
    
    import com.demo.entity.Student;
    import com.demo.exception.SysException;
    import com.demo.service.StudentService;
    import com.opensymphony.xwork2.Action;
    
    public class StudentAction implements Action { 
    
    	private StudentService studentService;
    
    	private String newName;
    
    	@Override
    	public String execute() throws Exception { 
    		return null;
    	}
    
    	public String saveStu() throws Exception { 
    		Student stu = new Student();
    		checkParams();
    		stu.setName(newName);
    		try { 
    			studentService.saveOne(stu);
    		} catch (Exception e) { 
    			StringWriter sw = new StringWriter();
    			PrintWriter pw = new PrintWriter(sw);
    			e.printStackTrace(pw);
    			System.out.println(sw.toString());
    			throw new SysException("\n" + sw.toString());
    		}
    		return SUCCESS;
    	}
    
    	/** * 校验请求参数 */
    	private void checkParams() throws SysException { 
    		if (newName == null) { 
    			throw new SysException("Name不能为空！");
    		}
    		newName = newName.trim();
    	}
    
    	/******************** get和set方法 ***************************/
    	public void setStudentService(StudentService studentService) { 
    		this.studentService = studentService;
    	}
    
    	public String getNewName() { 
    		return newName;
    	}
    
    	public void setNewName(String newName) { 
    		this.newName = newName;
    	}
    
    }

*  StudentService.java

package com.demo.service;
    
    import com.demo.entity.Student;
    
    public interface StudentService { 
    	
    	public void saveOne(Student stu);
    	
    }

*  StudentServiceImpl.java

package com.demo.service.impl;
    
    import org.springframework.transaction.annotation.Transactional;
    
    import com.demo.dao.StudentDao;
    import com.demo.entity.Student;
    import com.demo.service.StudentService;
    
    @Transactional
    public class StudentServiceImpl implements StudentService { 
    
    	private StudentDao studentDao;
    
    	public void saveOne(Student stu) { 
    		studentDao.saveOne(stu);
    	}
    
    	public void setStudentDao(StudentDao studentDao) { 
    		this.studentDao = studentDao;
    	}
    
    }

*  BaseDao.java

package com.demo.dao.impl;
    
    import org.hibernate.Session;
    import org.hibernate.SessionFactory;
    
    /** * 所有Dao层实现类都要继承该类，统一管理sessionFactory */
    public class BaseDao { 
    
    	private SessionFactory sessionFactory;
    
    	/** * 获取Session对象 */
    	public Session getSession() { 
    		return this.sessionFactory.getCurrentSession();
    	}
    
    	public SessionFactory getSessionFactory() { 
    		return sessionFactory;
    	}
    
    	public void setSessionFactory(SessionFactory sessionFactory) { 
    		this.sessionFactory = sessionFactory;
    	}
    
    }

*  StudentDao.java

package com.demo.dao;
    
    import com.demo.entity.Student;
    
    public interface StudentDao { 
    
    	public void saveOne(Student stu);
    
    }

*  StudentDaoImpl.java

package com.demo.dao;
    
    import com.demo.entity.Student;
    
    public interface StudentDao { 
    
    	public void saveOne(Student stu);
    
    }```
    - StudentDao.java
    ```java
    package com.demo.dao.impl;
    
    import com.demo.dao.StudentDao;
    import com.demo.entity.Student;
    
    public class StudentDaoImpl extends BaseDao implements StudentDao { 
    
    	public void saveOne(Student stu) { 
    		this.getSession().save(stu);
    	}
    }

至此，Spring与Hibernate已经整合完毕。  
  
  
（2）**Spring** 整合 **Struts2**：

> spring整合struts2比较简单，它们之间没有多少交互的地方，上面已经使用spring配置好了action中的bean，其他配置项几乎都是struts2一个人的。

*  web.xml

<filter>
    		<filter-name>struts2</filter-name>
    		<filter-class>org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter</filter-class>
    		<init-param>
    			<param-name>config</param-name>
    			<param-value>resources/struts.xml</param-value>
    		</init-param>
    	</filter>
    	<filter-mapping>
    		<filter-name>struts2</filter-name>
    		<url-pattern>/*</url-pattern>
    	</filter-mapping>

> 在web.xml中配置struts2的过滤器，用以处理前台页面发送来的请求，并根据指定的action配置下发到各个action处理请求。以上配置中的`init-param`指定了struts.xml文件的路径。因为这里的config路径变更，所有默认的struts-default.xml与struts-plugins.xml文件路径也必需在struts.xml中进行配置。

*  struts.xml

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.5//EN" "http://struts.apache.org/dtds/struts-2.5.dtd">
    <struts>
    	<include file="struts-default.xml" />
    	<include file="struts-plugin.xml" />
    	<include file="resources/struts2/struts-*.xml" />
    </struts>

> 为了方便模块管理，这里使用了通配符，只要是在`resources/struts2/`目录下，且以`struts-`开头的xml文件，均会被包含在内。

*  struts-student.xml

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.5//EN" "http://struts.apache.org/dtds/struts-2.5.dtd">
    <struts>
    	<package name="stuManage" namespace="/stuManage" extends="struts-default">
    		
    		<global-results>
    			
    			<result name="exception">/WEB-INF/pages/error.jsp</result>
    		</global-results>
    		
    		<global-exception-mappings>
    			<exception-mapping result="exception" exception="com.demo.exception.SysException"></exception-mapping>
    			<exception-mapping result="exception" exception="java.lang.Exception" />
    		</global-exception-mappings>
    		
    		<action name="saveStu" class="studentAction" method="saveStu">
    			<result name="success">/default.jsp</result>
    		</action>
    	</package>
    </struts>

>  *  这里用到了全局异常处理；
>  *  action中的`studentController`必须要与applicationContext\_action.xml中的beanid一致。服务器启动时，就会加载studentAction，并依次加载service和dao。  
>     ![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTMwMjA1OTM_size_16_color_FFFFFF_t_70 1]

*  index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    	pageEncoding="UTF-8"%>
    <!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>三大框架学习——主页</title>
    </head>
    <body>
    	<form action="stuManage/saveStu" method="post">
    		Name:<input type="text" name="newName"> <br> 
    		<input type="submit" value="保存学生信息">
    	</form>
    </body>
    </html>

*  success.jsp

*  error.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    	pageEncoding="UTF-8"%>
    <%@taglib prefix="s" uri="/struts-tags"%>
    <!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>错误页面</title>
    </head>
    <body>
    	<h1><font color="red">出错了！</font></h1>
    	<br>
    	<h3>错误信息：</h3>
    	<hr>
    	<font face="Courier New"><s:property value="exception.message" /></font>
    </body>
    </html>

struts2相关配置结束。  
你以为真的结束了吗？是的，但再完善一点，把日志的事解决了。

（3）日志配置

*  web.xml

<listener>
    		<listener-class>com.demo.listener.Log4j2ConfigListener</listener-class>
    	</listener>
    	<context-param>
    		<description>日志配置文件的路径</description>
    		<param-name>log4j.configurationFile</param-name>
    		<param-value>resources/log4j2.xml</param-value>
    	</context-param>

>  *  这里的Log4j2ConfigListener是自定义类；
>  *  日志配置文件指定到resources目录。

*  Log4j2ConfigListener

package com.demo.listener;
    
    import java.util.Enumeration;
    
    import javax.servlet.ServletContextEvent;
    import javax.servlet.ServletContextListener;
    
    import org.apache.logging.log4j.core.config.Configurator;
    
    public class Log4j2ConfigListener implements ServletContextListener { 
    	private static final String KEY = "log4j.configurationFile";
    
    	@Override
    	public void contextDestroyed(ServletContextEvent arg0) { 
    	}
    
    	@Override
    	public void contextInitialized(ServletContextEvent arg0) { 
    		String fileName = getContextParam(arg0);
    		Configurator.initialize("Log4j2", "classpath:" + fileName);
    	}
    
    	@SuppressWarnings("unchecked")
    	private String getContextParam(ServletContextEvent event) { 
    		Enumeration<String> names = event.getServletContext()
    				.getInitParameterNames();
    		while (names.hasMoreElements()) { 
    			String name = names.nextElement();
    			String value = event.getServletContext().getInitParameter(name);
    			if (name.trim().equals(KEY)) { 
    				return value;
    			}
    		}
    		return null;
    	}
    }

*  log4j2.xml

<?xml version="1.0" encoding="UTF-8"?>
    <Configuration status="warn">
    	<Appenders>
    		<Console name="Console" target="SYSTEM_OUT">
    			<PatternLayout pattern="[%-5p] %d %c - %m%n" />
    		</Console>
    		<File name="File" fileName="dist/my.log">
    			<PatternLayout pattern="%m%n" />
    		</File>
    	</Appenders>
    	<Loggers>
    		<Logger name="com.deml.log.Log4jTest2" level="INFO">
    			<AppenderRef ref="File" />
    		</Logger>
    		<Root level="INFO">
    			<AppenderRef ref="Console" />
    		</Root>
    	</Loggers>
    </Configuration>

>       内容太多了，对于没有耐心的读者来说这是一种折磨。其实，如果感兴趣的话可以按照本文的步骤先把项目搭建起来，然后再找出其中的知识点去复习。在自己捣鼓如何搭建web项目过程中虽然耗时，但好歹也搭建成功了，虽然不完美，但可以将就使用。  
>       这个实例只是简单地搭建了一下，在实际应用中有很多业务场景要去实现，可以在这个模板的基础之上，导包，完善下去，相信在这个过程中，会对三大框架更加了解。

全文结束！

[Link 1]: https://blog.csdn.net/u013020593/article/details/90483914
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTMwMjA1OTM_size_16_color_FFFFFF_t_70]: /images/20220128/1cfd4f51870c4b359b40706658c26dd5.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTMwMjA1OTM_size_16_color_FFFFFF_t_70 1]: /images/20220128/42da0a79b5cb4fa29db4039d8384affa.png