Spring+Druid+SpringMVC的搭建（附Demo）

時間 2019-11-08

標籤 spring+druid+springmvc spring druid springmvc 搭建 demo 欄目 Spring 简体版

原文原文鏈接

最近公司事情比較少，便想利用這段空閒時間作一個本身的博客。html

前端界面已經搞好，感謝楊姐的模板，本身稍微把模板沒有的模塊給補全了。前端

今天便開始本身的SSM框架搭建，數據庫連接是採用數據庫鏈接池。先上個項目結構圖：java

這個是基於Maven搭建的ssm框架，我把service層刪除了，去掉了dao層接口，業務在須要與數據庫交互的時候便直接調用dao層的方法。mysql

一、建立maven項目，maven沒有接觸過的請自行百度 maven項目在eclisp如何建立。git

二、配置 pom.xml 加載jar包github

<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/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.cwj</groupId>
  <artifactId>MyBlog</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>MyBlog Maven Webapp</name>
  <url>http://maven.apache.org</url>
    <properties>  
        <!-- spring版本號 -->  
        <spring.version>4.0.2.RELEASE</spring.version>  
        <!-- mybatis版本號 -->  
        <mybatis.version>3.2.6</mybatis.version>  
        <!-- log4j日誌文件管理包版本 -->  
        <slf4j.version>1.7.7</slf4j.version>  
        <log4j.version>1.2.17</log4j.version>  
    </properties> 
    
    <dependencies>
        <!-- DBCP -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.13</version>
        </dependency>
    
        <!-- junit -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
             <!-- 表示開發的時候引入，發佈的時候不會加載此包 -->  
            <scope>test</scope>
        </dependency>
        
         <!-- spring核心包 -->  
        <dependency>  
            <groupId>org.springframework</groupId>  
            <artifactId>spring-core</artifactId>  
            <version>${spring.version}</version>  
        </dependency>  
  
        <dependency>  
            <groupId>org.springframework</groupId>  
            <artifactId>spring-web</artifactId>  
            <version>${spring.version}</version>  
        </dependency>  
        <dependency>  
            <groupId>org.springframework</groupId>  
            <artifactId>spring-oxm</artifactId>  
            <version>${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-jdbc</artifactId>  
            <version>${spring.version}</version>  
        </dependency>  
  
        <dependency>  
            <groupId>org.springframework</groupId>  
            <artifactId>spring-webmvc</artifactId>  
            <version>${spring.version}</version>  
        </dependency>  
        <dependency>  
            <groupId>org.springframework</groupId>  
            <artifactId>spring-aop</artifactId>  
            <version>${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-test</artifactId>  
            <version>${spring.version}</version>  
        </dependency>  
        <!-- mybatis核心包 -->  
        <dependency>  
            <groupId>org.mybatis</groupId>  
            <artifactId>mybatis</artifactId>  
            <version>${mybatis.version}</version>  
        </dependency>  
         <!-- mybatis/spring包 -->  
        <dependency>  
            <groupId>org.mybatis</groupId>  
            <artifactId>mybatis-spring</artifactId>  
            <version>1.2.2</version>  
        </dependency>  
        
         <!-- 導入java ee jar 包 -->  
        <dependency>  
            <groupId>javax</groupId>  
            <artifactId>javaee-api</artifactId>  
            <version>7.0</version>  
        </dependency>  
        
         <!-- 導入Mysql數據庫連接jar包 -->  
        <dependency>  
            <groupId>mysql</groupId>  
            <artifactId>mysql-connector-java</artifactId>  
            <version>5.1.36</version>  
        </dependency>  
        <!-- 導入dbcp的jar包，用來在applicationContext.xml中配置數據庫 -->  
        <dependency>  
            <groupId>commons-dbcp</groupId>  
            <artifactId>commons-dbcp</artifactId>  
            <version>1.2.2</version>  
        </dependency>  
        
        <!-- JSTL標籤類 -->  
        <dependency>  
            <groupId>jstl</groupId>  
            <artifactId>jstl</artifactId>  
            <version>1.2</version>  
        </dependency>  
        <!-- 日誌文件管理包 -->  
        <!-- log start -->  
        <dependency>  
            <groupId>log4j</groupId>  
            <artifactId>log4j</artifactId>  
            <version>${log4j.version}</version>  
        </dependency>  
          
          
        <!-- 格式化對象，方便輸出日誌 -->  
        <dependency>  
            <groupId>com.alibaba</groupId>  
            <artifactId>fastjson</artifactId>  
            <version>1.1.41</version>  
        </dependency>  
  
  
        <dependency>  
            <groupId>org.slf4j</groupId>  
            <artifactId>slf4j-api</artifactId>  
            <version>${slf4j.version}</version>  
        </dependency>  
  
        <dependency>  
            <groupId>org.slf4j</groupId>  
            <artifactId>slf4j-log4j12</artifactId>  
            <version>${slf4j.version}</version>  
        </dependency>  
        <!-- log end -->  
        <!-- 映入JSON -->  
        <dependency>  
            <groupId>org.codehaus.jackson</groupId>  
            <artifactId>jackson-mapper-asl</artifactId>  
            <version>1.9.13</version>  
        </dependency>  
        <!-- 上傳組件包 -->  
        <dependency>  
            <groupId>commons-fileupload</groupId>  
            <artifactId>commons-fileupload</artifactId>  
            <version>1.3.1</version>  
        </dependency>  
        <dependency>  
            <groupId>commons-io</groupId>  
            <artifactId>commons-io</artifactId>  
            <version>2.4</version>  
        </dependency>  
        <dependency>  
            <groupId>commons-codec</groupId>  
            <artifactId>commons-codec</artifactId>  
            <version>1.9</version>  
        </dependency>  

    </dependencies>

  <build>
    <finalName>MyBlog</finalName>
  </build>
</project>

三、在src/main/java跟目錄下建好須要的包web

四、在src/main/resource下建立spring-mvc.xmlspring

 1 <?xml version="1.0" encoding="UTF-8"?>  
 2 <beans xmlns="http://www.springframework.org/schema/beans"  
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"  
 4     xmlns:context="http://www.springframework.org/schema/context"  
 5     xmlns:mvc="http://www.springframework.org/schema/mvc"  
 6     xsi:schemaLocation="http://www.springframework.org/schema/beans    
 7                         http://www.springframework.org/schema/beans/spring-beans-3.1.xsd    
 8                         http://www.springframework.org/schema/context    
 9                         http://www.springframework.org/schema/context/spring-context-3.1.xsd    
10                         http://www.springframework.org/schema/mvc    
11                         http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">  
12     <!-- 自動掃描該包，使SpringMVC認爲包下用了@controller註解的類是控制器 -->  
13     <context:component-scan base-package="com.cwj.controller" />  
14     <!-- 擴充了註解驅動，能夠將請求參數綁定到控制器參數 -->
15     <mvc:annotation-driven/>
16     
17     <!-- 靜態文件處理  -->
18     <!-- location:表示/assets/目錄下（即服務器根目錄）的static包下的全部文件 -->
19     <!-- mapping:表示以/static開頭的全部請求路徑，如/static/a 或者/static/a/b -->
20     <mvc:resources location="/assets/" mapping="/public/**/" />
21     
22     <!--避免IE執行AJAX時，返回JSON出現下載文件 -->  
23     <bean id="mappingJacksonHttpMessageConverter"  
24         class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">  
25         <property name="supportedMediaTypes">  
26             <list>  
27                 <value>text/html;charset=UTF-8</value>  
28             </list>  
29         </property>  
30     </bean>  
31     <!-- 啓動SpringMVC的註解功能，完成請求和註解POJO的映射 -->  
32     <bean  
33         class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">  
34         <property name="messageConverters">  
35             <list>  
36                 <ref bean="mappingJacksonHttpMessageConverter" /> <!-- JSON轉換器 -->  
37             </list>  
38         </property>  
39     </bean>  
40       
41     <!-- 配置文件上傳，若是沒有使用文件上傳能夠不用配置，固然若是不配，那麼配置文件中也沒必要引入上傳組件包 -->  
42     <bean id="multipartResolver"    
43         class="org.springframework.web.multipart.commons.CommonsMultipartResolver">    
44         <!-- 默認編碼 -->  
45         <property name="defaultEncoding" value="utf-8" />    
46         <!-- 文件大小最大值 -->  
47         <property name="maxUploadSize" value="10485760000" />    
48         <!-- 內存中的最大值 -->  
49         <property name="maxInMemorySize" value="40960" />    
50         <!-- 啓用是爲了推遲文件解析，以便捕獲文件大小異常 -->
51         <property name="resolveLazily" value="true"/>
52     </bean>   
53     
54     <!-- 配置ViewResolver 。可用多個ViewResolver 。使用order屬性排序。   InternalResourceViewResolver 放在最後-->
55     <bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
56     <property name="order" value="1"></property>
57         <property name="mediaTypes">
58             <map>
59                 <!-- 告訴視圖解析器，返回的類型爲json格式 -->
60                 <entry key="json" value="application/json" />
61                 <entry key="xml" value="application/xml" />
62                 <entry key="htm" value="text/htm" />
63             </map>
64         </property>
65         <property name="defaultViews">
66             <list>
67                 <!-- ModelAndView裏的數據變成JSON -->
68                 <bean class="org.springframework.web.servlet.view.json.MappingJacksonJsonView" />
69             </list>
70         </property>
71         <property name="ignoreAcceptHeader" value="true"></property>
72     </bean>
73     
74    <!-- 定義跳轉的文件的先後綴 ，視圖模式配置-->  
75     <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">  
76         <!-- 這裏的配置個人理解是自動給後面action的方法return的字符串加上前綴和後綴，變成一個 可用的url地址 -->  
77         <property name="prefix" value="/WEB-INF/view/" />  
78         <property name="suffix" value=".jsp" />  
79     </bean>  
80 </beans>

五、配置好web.xml就能夠測試剛剛配置的Spring+SpringMVC有沒有成功。等會兒，所有配置完，記得把註釋給取消掉。sql

 1 <?xml version="1.0" encoding="UTF-8"?>  
 2 <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
 3     xmlns="http://java.sun.com/xml/ns/javaee"  
 4     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"  
 5     version="3.0">  
 6     <display-name>Archetype Created Web Application</display-name>  
 7     <!-- Spring和mybatis的配置文件 -->  
 8 <!--     <context-param>  
 9         <param-name>contextConfigLocation</param-name>  
10         <param-value>classpath:spring-mybatis.xml</param-value>  
11     </context-param>    -->
12     <!-- 編碼過濾器 -->  
13     <filter>  
14         <filter-name>encodingFilter</filter-name>  
15         <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>  
16         <async-supported>true</async-supported>  
17         <init-param>  
18             <param-name>encoding</param-name>  
19             <param-value>UTF-8</param-value>  
20         </init-param>  
21     </filter>  
22     <filter-mapping>  
23         <filter-name>encodingFilter</filter-name>  
24         <url-pattern>/*</url-pattern>  
25     </filter-mapping>  
26     <!-- Spring監聽器 -->  
27 <!--      <listener>  
28         <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  
29     </listener>   --> 
30     <!-- 防止Spring內存溢出監聽器 -->  
31 <!--      <listener>  
32         <listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class>  
33     </listener>   -->
34   
35     <!-- Spring MVC servlet -->  
36     <servlet>  
37         <servlet-name>SpringMVC</servlet-name>  
38         <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  
39         <init-param>  
40             <param-name>contextConfigLocation</param-name>  
41             <param-value>classpath:spring-mvc.xml</param-value>  
42         </init-param>  
43         <load-on-startup>1</load-on-startup>  
44         <async-supported>true</async-supported>  
45     </servlet>  
46     <servlet-mapping>  
47         <servlet-name>SpringMVC</servlet-name>  
48         <!-- 此處能夠能夠配置成*.do，對應struts的後綴習慣 -->  
49         <url-pattern>/</url-pattern>  
50     </servlet-mapping>  
51     <welcome-file-list>  
52         <welcome-file>/index.jsp</welcome-file>  
53     </welcome-file-list>  
54   
55 </web-app>

六、在com.cwj.controller包下建立一個StudentController.java控制器數據庫

 1 package com.cwj.controller;
 2 
 3 import org.springframework.stereotype.Controller;
 4 import org.springframework.web.bind.annotation.RequestMapping;
 5 
 6 @Controller
 7 public class StudentController {
 8     
 9     @RequestMapping(value="/test")
10     public String test(){
11 
12         return "com/test";
13     }
14 }

七、根據配置的路徑，建立相應的test.jsp文件，以後在tomcat中運行。

八、接下來就是配置spring-mybatis.首先建立application.properties 配置數據庫鏈接信息

 1 jdbc.driver=com.mysql.jdbc.Driver
 2 jdbc.url=jdbc\:mysql\://rm-wz92wfb0l40ny7b5jo.mysql.rds.aliyuncs.com\:3306/test
 3 jdbc.username=root
 4 jdbc.password=CHen123456
 5 
 6 #定義初始鏈接數  
 7 jdbc.initialSize=0
 8 #定義最大鏈接數  
 9 jdbc.maxActive=20
10 #定義最大空閒  
11 jdbc.maxIdle=20
12 #定義最小空閒  
13 jdbc.minIdle=1
14 #定義最長等待時間  
15 jdbc.maxWait=60000
16 
17 dbcp.initialSize=15
18 dbcp.maxActive=5000
19 dbcp.maxIdle=0
20 dbcp.maxWait=900000
21 dbcp.defaultAutoCommit=true
22 dbcp.removeAbandoned=true
23 dbcp.removeAbandonedTimeout=30
24 dbcp.whenExhaustedAction=1
25 dbcp.validationQuery=select 1
26 dbcp.testOnBorrow=fasle
27 dbcp.testOnReturn=false

九、配置log4j.properties信息

log4j.rootLogger=INFO,Console,File  
log4j.appender.Console=org.apache.log4j.ConsoleAppender  
log4j.appender.Console.Target=System.out  
log4j.appender.Console.layout = org.apache.log4j.PatternLayout  
log4j.appender.Console.layout.ConversionPattern=[%c] - %m%n  
  
log4j.appender.File = org.apache.log4j.RollingFileAppender  
log4j.appender.File.File = logs/ssm.log  
log4j.appender.File.MaxFileSize = 10MB  
log4j.appender.File.Threshold = ALL  
log4j.appender.File.layout = org.apache.log4j.PatternLayout  
log4j.appender.File.layout.ConversionPattern =[%p] [%d{yyyy-MM-dd HH\:mm\:ss}][%c]%m%n

十、配置spring-mybatis.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: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-3.1.xsd    
                        http://www.springframework.org/schema/context    
                        http://www.springframework.org/schema/context/spring-context-3.1.xsd    
                        http://www.springframework.org/schema/mvc    
                        http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">  
    <!-- 自動掃描 -->  
    <context:component-scan base-package="com.cwj" />  
    
    <!-- 引入配置文件 -->  
    <bean id="propertyConfigurer"  
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">  
        <property name="location" value="classpath:application.properties" />  
    </bean>  
  
          <!-- 數據源配置,使用應用內的DBCP數據庫鏈接池     -->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource"  init-method="init" destroy-method="close">
        <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="${dbcp.initialSize}" />
        <property name="maxActive" value="${dbcp.maxActive}" />
        <property name="maxIdle" value="${dbcp.maxIdle}" />
        <property name="maxWait" value="${dbcp.maxWait}" />
        <property name="defaultAutoCommit" value="${dbcp.defaultAutoCommit}" />
        <property name="removeAbandoned" value="${dbcp.removeAbandoned}" />
        <property name="removeAbandonedTimeout" value="${dbcp.removeAbandonedTimeout}" />
        <property name="logAbandoned" value="true"></property>
        
        <!-- 配置間隔多久才進行一次檢測，檢測須要關閉的空閒鏈接，單位是毫秒 -->
        <property name="timeBetweenEvictionRunsMillis" value="60000" />
        <!-- 配置一個鏈接在池中最小生存的時間，單位是毫秒 -->
        <property name="minEvictableIdleTimeMillis" value="300000" />
        <property name="validationQuery" value="${dbcp.validationQuery}" />
        <property name="testWhileIdle" value="true" />
        <property name="testOnBorrow" value="false" />
        <property name="testOnReturn" value="false" />
        
        <!-- 打開PSCache，而且指定每一個鏈接上PSCache的大小 若是用Oracle，則把poolPreparedStatements配置爲true，mysql能夠配置爲false。分庫分表較多的數據庫，建議配置爲false。-->
        <property name="poolPreparedStatements" value="false" />
        <property name="maxPoolPreparedStatementPerConnectionSize" value="20" />
        <!-- 配置監控統計攔截的filters -->
        <property name="filters" value="stat" /> 
    </bean>
  
    <!-- spring jdbc  NamedParameterJdbcTemplate -->
    <bean id="namedjdbctemp" class="org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate">
        <constructor-arg ref="dataSource"/>
    </bean>
  
    <!-- spring和MyBatis完美整合，不須要mybatis的配置映射文件 -->  
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">  
        <property name="dataSource" ref="dataSource" />  
        <!-- 自動掃描mapping.xml文件 -->  
       <!--  <property name="mapperLocations" value="classpath:com/cwj/mapping/*.xml"></property>   -->
    </bean>  
  
    <!-- DAO接口所在包名，Spring會自動查找其下的類 -->  
     <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">  
        <property name="basePackage" value="com.cwj.dao" />  
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>  
    </bean>   
  
    <!-- (事務管理)transaction manager, use JtaTransactionManager for global tx -->  
    <bean id="transactionManager"  
        class="org.springframework.jdbc.datasource.DataSourceTransactionManager">  
        <property name="dataSource" ref="dataSource" />  
    </bean> 
  
</beans>

十一、最後測試配置是否成功。

數據庫表是這樣的

DROP TABLE IF EXISTS `student`;
CREATE TABLE `student` (
  `id` varchar(32) NOT NULL DEFAULT '',
  `name` varchar(255) DEFAULT NULL,
  `age` smallint(6) DEFAULT NULL,
  `sex` smallint(6) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

十二、建立實體類Student.java

package com.cwj.pojo;

import javax.persistence.Entity;

@Entity
public class Student {
    private String id;
    private String name;
    private Integer sex;
    private Integer age;
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public Integer getSex() {
        return sex;
    }
    public void setSex(Integer sex) {
        this.sex = sex;
    }
    public Integer getAge() {
        return age;
    }
    public void setAge(Integer age) {
        this.age = age;
    }
    @Override
    public String toString() {
        return "Student [id=" + id + ", name=" + name + ", sex=" + sex + ", age=" + age + "]";
    }
    
    
}

1三、建立StudentDao

package com.cwj.dao;

import java.util.HashMap;
import java.util.Map;

import javax.annotation.Resource;

import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate;
import org.springframework.stereotype.Repository;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import com.cwj.pojo.Student;

@Repository
public class  StudentDao {
    
    
    
    @Resource
    private NamedParameterJdbcTemplate namedjdbctemp;
    

    @Transactional
    public Student queryStuById(String id){
        String sql = "select * from student where id =:id";
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("id", id);
        return namedjdbctemp.queryForObject(sql, map,new BeanPropertyRowMapper<Student>(Student.class));
    }
    
}

14修改StudentController

package com.cwj.controller;

import javax.servlet.http.HttpServletRequest;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.cwj.dao.StudentDao;
import com.cwj.pojo.Student;

@Controller
public class StudentController {
    
    private static Logger log=LoggerFactory.getLogger(StudentController.class);
    
    @Autowired
    private StudentDao studentService;
    
    @RequestMapping(value="/test")
    public String test(HttpServletRequest request){
        Student student = studentService.queryStuById("2");
        request.setAttribute("stu", student);
        log.info("stu:"+student.toString());
        return "com/test";
    }
}

1五、修改test.jsp

 1 package com.cwj.controller;
 2 
 3 import javax.servlet.http.HttpServletRequest;
 4 
 5 import org.slf4j.Logger;
 6 import org.slf4j.LoggerFactory;
 7 import org.springframework.beans.factory.annotation.Autowired;
 8 import org.springframework.stereotype.Controller;
 9 import org.springframework.web.bind.annotation.RequestMapping;
10 
11 import com.cwj.dao.StudentDao;
12 import com.cwj.pojo.Student;
13 
14 @Controller
15 public class StudentController {
16     
17     private static Logger log=LoggerFactory.getLogger(StudentController.class);
18     
19     @Autowired
20     private StudentDao studentService;
21     
22     @RequestMapping(value="/test")
23     public String test(HttpServletRequest request){
24         Student student = studentService.queryStuById("2");
25         request.setAttribute("stu", student);
26         log.info("stu:"+student.toString());
27         return "com/test";
28     }
29 }