玩转 SSH（六）：SpringMVC + MyBatis 架构搭建（注解版）

一、创建 SSMVCAnnoDemo 项目

点击菜单，选择“File -> New Project” 创建新项目。选择使用 archetype 中的 maven-webapp 模版创建。

输入对应的项目坐标GroupId 和 ArtifactId

之后在项目名称中填入项目名称，这里我填的 ProjectName 和上文的 ArtifactId 相同，都是 SSMVCAnnoDemo。

点击确定后，等待 Maven 帮我们构建好项目的目录结构。当控制台显示 BUILD SUCCESS 就表示初始化完成了。

初始化完成后的目录结构是这样的：

在 main 目录下创建 java 目录并将其设置为源码目录：

之后创建 com.chanshuyi.action 等包，创建完成后的目录结构如下：

二、导入依赖的包和插件

设置 POM.XML 配置文件中的全局属性：

<!-- 声明全局属性 -->
<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <struts.version>2.3.24</struts.version>
    <springframework.version>4.1.6.RELEASE</springframework.version>
    <junit.version>3.8.1</junit.version>
    <commonsLogging.version>1.2</commonsLogging.version>
</properties>

依次引入 MyBatis、Spring、SpringMVC、MySQL、Druid、JUnit、Log4J 等的依赖 Jar 包：

<!-- ********************** MyBatis ********************** -->
<!-- MyBatis 核心包 -->
<dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis</artifactId>
    <version>3.1.1</version>
</dependency>
<!-- 添加mybatis与Spring整合的核心包 -->
<dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis-spring</artifactId>
    <version>1.1.1</version>
</dependency>

<!-- ********************** Spring ********************** -->
<!-- Spring MVC 依赖 -->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>${springframework.version}</version>
</dependency>
<!-- 添加Spring-core包 -->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-core</artifactId>
    <version>${springframework.version}</version>
</dependency>
<!-- 添加spring-tx包 -->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-tx</artifactId>
    <version>${springframework.version}</version>
</dependency>
<!-- Spring ORM 相关-->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-orm</artifactId>
    <version>${springframework.version}</version>
</dependency>
<!-- 添加spring-jdbc包 -->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jdbc</artifactId>
    <version>${springframework.version}</version>
</dependency>
<!--添加spring-web包 -->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>${springframework.version}</version>
</dependency>
<!-- 添加spring-context包 -->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>${springframework.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-beans</artifactId>
    <version>${springframework.version}</version>
</dependency>
<dependency>
    <groupId>commons-logging</groupId>
    <artifactId>commons-logging</artifactId>
    <version>${commonsLogging.version}</version>
</dependency>
<!--添加aspectjweaver包 -->
<dependency>
    <groupId>org.aspectj</groupId>
    <artifactId>aspectjweaver</artifactId>
    <version>1.8.5</version>
</dependency>

<!-- ********************** Spring MVC 依赖的jar包 **********************-->
<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>
</dependency>
<dependency>
    <groupId>taglibs</groupId>
    <artifactId>standard</artifactId>
    <version>1.1.2</version>
</dependency>
<!-- Servelt API -->
<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>3.0.1</version>
    <scope>provided</scope>
</dependency>

<!-- ********************** DB Connection ********************** -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.21</version>
</dependency>
<!-- Druid -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.0.6</version>
</dependency>

<!-- ********************** 其他 ********************** -->
<!-- 单元测试 JUnit -->
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>${junit.version}</version>
    <scope>test</scope>
</dependency>
<!-- 日志记录 Log4j -->
<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-api</artifactId>
    <version>1.7.6</version>
</dependency>
<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-log4j12</artifactId>
    <version>1.7.6</version>
</dependency>

之后导入 Tomcat 启动插件，我们将通过 Maven 方式启动 Tomcat，这样就不必在本地配置一个 Tomcat 服务器。

<!--  Maven的Tomcat插件（支持Maven以"tomcat7:run"方式启动web项目）  -->
<plugin>
    <groupId>org.apache.tomcat.maven</groupId>
    <artifactId>tomcat7-maven-plugin</artifactId>
    <version>2.1</version>
    <configuration>
        <port>5050</port>
        <path>/</path>
        <uriEncoding>UTF-8</uriEncoding>
        <finalName>mgr</finalName>
        <server>tomcat7</server>
    </configuration>
</plugin>

配置完成后的 POM.XML 是这样的：

<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.chanshuyi.SSMVCAnnoDemo</groupId>
  <artifactId>SSMVCAnnoDemo</artifactId>
  <packaging>war</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>SSMVCAnnoDemo Maven Webapp</name>
  <url>http://maven.apache.org</url>

    <!-- 声明全局属性 -->
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <struts.version>2.3.24</struts.version>
        <springframework.version>4.1.6.RELEASE</springframework.version>
        <junit.version>3.8.1</junit.version>
        <commonsLogging.version>1.2</commonsLogging.version>
    </properties>

    <dependencies>
        <!-- ********************** MyBatis ********************** -->
        <!-- MyBatis 核心包 -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.1.1</version>
        </dependency>
        <!-- 添加mybatis与Spring整合的核心包 -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>1.1.1</version>
        </dependency>

        <!-- ********************** Spring ********************** -->
        <!-- Spring MVC 依赖 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${springframework.version}</version>
        </dependency>
        <!-- 添加Spring-core包 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${springframework.version}</version>
        </dependency>
        <!-- 添加spring-tx包 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>${springframework.version}</version>
        </dependency>
        <!-- Spring ORM 相关-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-orm</artifactId>
            <version>${springframework.version}</version>
        </dependency>
        <!-- 添加spring-jdbc包 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>${springframework.version}</version>
        </dependency>
        <!--添加spring-web包 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${springframework.version}</version>
        </dependency>
        <!-- 添加spring-context包 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${springframework.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>${springframework.version}</version>
        </dependency>
        <dependency>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
            <version>${commonsLogging.version}</version>
        </dependency>
        <!--添加aspectjweaver包 -->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.8.5</version>
        </dependency>

        <!-- ********************** Spring MVC 依赖的jar包 **********************-->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>
        <dependency>
            <groupId>taglibs</groupId>
            <artifactId>standard</artifactId>
            <version>1.1.2</version>
        </dependency>
        <!-- Servelt API -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.0.1</version>
            <scope>provided</scope>
        </dependency>

        <!-- ********************** DB Connection ********************** -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.21</version>
        </dependency>
        <!-- Druid -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.6</version>
        </dependency>

        <!-- ********************** 其他 ********************** -->
        <!-- 单元测试 JUnit -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>${junit.version}</version>
            <scope>test</scope>
        </dependency>
        <!-- 日志记录 Log4j -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.6</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.7.6</version>
        </dependency>
    </dependencies>

  <build>
    <finalName>SSMVCAnnoDemo</finalName>
      <plugins>
          <!--  Maven的Tomcat插件（支持Maven以"tomcat7:run"方式启动web项目）  -->
          <plugin>
              <groupId>org.apache.tomcat.maven</groupId>
              <artifactId>tomcat7-maven-plugin</artifactId>
              <version>2.1</version>
              <configuration>
                  <port>5050</port>
                  <path>/</path>
                  <uriEncoding>UTF-8</uriEncoding>
                  <finalName>mgr</finalName>
                  <server>tomcat7</server>
              </configuration>
          </plugin>
      </plugins>
  </build>
</project>

三、开发模型层（MyBatis）

创建 SpringMVC 配置文件 resources/spring-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:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:p="http://www.springframework.org/schema/p"
       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.xsd  
            http://www.springframework.org/schema/context  
            http://www.springframework.org/schema/context/spring-context.xsd"
       default-lazy-init="true">

    <!-- 添加注解驱动 -->
    <mvc:annotation-driven />
    <!-- 默认扫描的包路径 -->
    <context:component-scan base-package="com.chanshuyi.controller, com.chanshuyi.service.impl, com.chanshuyi.dao.impl" />

    <!-- mvc:view-controller可以在不需要Controller处理request的情况，转向到设置的View -->
    <!-- 像下面这样设置，如果请求为/，则不通过controller，而直接解析为/index.jsp -->
    <!--<mvc:view-controller path="/" view-name="index" />-->
    <!-- 配置 SpringMVC Controller 转发JSP页面的路径 -->
    <bean class="org.springframework.web.servlet.view.UrlBasedViewResolver">
        <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"></property>
        <!-- 配置jsp路径前缀 -->
        <property name="prefix" value="/"></property>
        <!-- 配置URl后缀 -->
        <property name="suffix" value=".jsp"></property>
    </bean>

    <!--  ================================== import sub-config file  ================================== -->
    <import resource="spring-mybatis.xml" />
    <!--  ================================== /import sub-config file  ================================== -->
</beans>  

创建 spring-mybatis.xml 文件，配置一个只读的数据源以及一个只写的数据源

<?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">

    <!-- 引入外部properties文件 -->
    <context:property-placeholder location="classpath:jdbc.properties" />

    <!-- ====================================================== Add MyBatis Support Start ====================================================== -->
    <!-- 配置写数据源 -->
    <bean id="dataSourceWrite" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
        <!-- 基本属性 url、user、password -->
        <property name="url" value="${jdbc.master.url}" />
        <property name="username" value="${jdbc.master.username}" />
        <property name="password" value="${jdbc.master.password}" />
        <!-- 配置初始化大小、最小、最大 -->
        <property name="initialSize" value="${jdbc.master.initialSize}" />
        <property name="minIdle" value="${jdbc.master.minIdle}" />
        <property name="maxActive" value="${jdbc.master.maxActive}" />
        <!-- 配置获取连接等待超时的时间 -->
        <property name="maxWait" value="60000" />
        <!-- 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒 -->
        <property name="timeBetweenEvictionRunsMillis" value="60000" />
        <!-- 配置一个连接在池中最小生存的时间，单位是毫秒 -->
        <property name="minEvictableIdleTimeMillis" value="300000" />
        <property name="validationQuery" value="SELECT '1'" />
        <property name="testWhileIdle" value="true" />
        <property name="testOnBorrow" value="true" />
        <property name="testOnReturn" value="false" />
        <!-- 打开PSCache，并且指定每个连接上PSCache的大小 mysql false -->
        <property name="poolPreparedStatements" value="false" />
        <property name="maxPoolPreparedStatementPerConnectionSize" value="20" />
        <!-- 配置监控统计拦截的filters -->
        <property name="filters" value="config,stat,log4j,wall" />
        <property name="connectionProperties" value="config.decrypt=false" />
    </bean>
    <!-- 配置读数据源 -->
    <bean id="dataSourceRead" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
        <!-- 基本属性 url、user、password -->
        <property name="url" value="${jdbc.slave.url}" />
        <property name="username" value="${jdbc.slave.username}" />
        <property name="password" value="${jdbc.slave.password}" />
        <!-- 配置初始化大小、最小、最大 -->
        <property name="initialSize" value="${jdbc.slave.initialSize}" />
        <property name="minIdle" value="${jdbc.slave.minIdle}" />
        <property name="maxActive" value="${jdbc.slave.maxActive}" />
        <!-- 配置获取连接等待超时的时间 -->
        <property name="maxWait" value="60000" />
        <!-- 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒 -->
        <property name="timeBetweenEvictionRunsMillis" value="60000" />
        <!-- 配置一个连接在池中最小生存的时间，单位是毫秒 -->
        <property name="minEvictableIdleTimeMillis" value="300000" />
        <property name="validationQuery" value="SELECT '1'" />
        <property name="testWhileIdle" value="true" />
        <property name="testOnBorrow" value="false" />
        <property name="testOnReturn" value="false" />
        <!-- 打开PSCache，并且指定每个连接上PSCache的大小 mysql false -->
        <property name="poolPreparedStatements" value="false" />
        <property name="maxPoolPreparedStatementPerConnectionSize" value="20" />
        <!-- 配置监控统计拦截的filters -->
        <property name="filters" value="config,stat,log4j,wall" />
        <property name="connectionProperties" value="config.decrypt=false" />
    </bean>

    <!-- 可写的SessionFactory -->
    <bean id="sqlWriteSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean" scope="singleton">
        <property name="dataSource" ref="dataSourceWrite" />
        <property name="configLocation" value="classpath:mybatis-config.xml" />
    </bean>
    <!-- 只读的SessionFactory -->
    <bean id="sqlReadOnlySessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean" scope="singleton">
        <property name="dataSource" ref="dataSourceRead" />
        <property name="configLocation" value="classpath:mybatis-config.xml" />
    </bean>

    <!-- 可写的Session -->
    <bean id="writableSQLSession" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg index="0" ref="sqlWriteSessionFactory" />
    </bean>
    <!-- 只读的Session -->
    <bean id="readonlySQLSession" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg index="0" ref="sqlReadOnlySessionFactory" />
    </bean>
    <!-- ====================================================== Add MyBatis Support End ====================================================== -->
</beans>

创建 jdbc.properties 配置文件

############################  MySQL/Oracle/SQLServer Database Configuratioin Info ###############################
# MySQL Master DB Info
jdbc.master.dialet=org.hibernate.dialect.MySQLDialect
jdbc.master.driverClassName=com.mysql.jdbc.Driver
jdbc.master.url=jdbc:mysql://127.0.0.1:3306/SSMDemo
jdbc.master.username=root
jdbc.master.password=sa

# MySQL Slave DB Info
jdbc.slave.dialet=org.hibernate.dialect.MySQLDialect
jdbc.slave.driverClassName=com.mysql.jdbc.Driver
jdbc.slave.url=jdbc:mysql://localhost:3306/SSMDemo
jdbc.slave.username=root
jdbc.slave.password=sa

############################## Connection Pool Configuration Info ##############################################
# MySQL Master DB Setting
jdbc.master.initialSize = 10
jdbc.master.minIdle = 0
jdbc.master.maxActive = 30

# MySQL Slave DB Setting
jdbc.slave.initialSize = 10
jdbc.slave.minIdle = 0
jdbc.slave.maxActive = 30

在本地 MySQL 数据库创建一个 SSMDemo 数据库，执行下面的语句创建 user 表并插入一条测试数据。

CREATE TABLE `user` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `username` varchar(45) DEFAULT NULL,
  `password` varchar(45) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of user
-- ----------------------------
INSERT INTO `user` VALUES ('1', 'admin', 'password');

创建 mybatis-config.xml 文件，并配置需要扫描包路径

<?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> 
    <mappers>
        <!-- 配置扫描的Mapper类 -->
        <package name="com.chanshuyi.dao.mapper"/>
    </mappers>
</configuration>

下载 MBGGenerator（密码：c1dy），这是MyBatis 官方的 MyBatis Generator，我们使用它将数据库表转化成 model、mapper 以及 SqlProvider 文件。

下载文件解压放到 resources 目录下。进入 resources/mbg 目录，双击运行 generate.bat，程序自动将配置文件 resources/mbgconfig.xml 中配置的表格映射成相对应的文件。

四、开发视图层（Spring）

创建 resources/log4j.properties 文件，提供日志记录。

#Console Log
log4j.rootLogger=info, console, file

# Write to Console
log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.Threshold=INFO
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=%5p %d{MM-dd HH:mm:ss}(%F:%L): %m%n

# Write to File
log4j.appender.file=org.apache.log4j.DailyRollingFileAppender
log4j.appender.file.File=${catalina.home}app/log/log.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%5p %d{MM-dd HH:mm:ss}(%F:%L): %m%n

在 com.chanshuyi.dao.mapper.UserMapper 类中增加 getUserListByMapSql 接口：

/**
 * 根据参数构造SQL进行查询
 * @param param
 * @return
 */
@SelectProvider(type = UserSqlProvider.class, method = "getUserListByMapSql")
List<User> getUserListByMapSql(@Param("param") Map<String, String> param);

在 UserSqlProvider 类增加对上面接口 SQL 的实现：

/**
 * 获取查询SQL
 * @param param
 * @return
 */
public String getUserListByMapSql(Map<String, Object> param) {
    StringBuilder builder = new StringBuilder();
    Map<String, String> realParam = (Map<String, String>)param.get("param");

    //add select part
    builder.append(" select * from user where 1 = 1 ");

    //add condition part
    String conditionStr = "";
    if(!StringUtil.isNullOrEmpty(realParam)){
        conditionStr = getQueryCondition(realParam);
        if(!StringUtil.isNullOrEmpty(conditionStr)){
            builder.append(conditionStr);
        }
    }

    return new String(builder);
}

public String getQueryCondition(Map<String, String> param){
    StringBuilder builder = new StringBuilder();

    //if param is null or empty, return empty String
    if(param == null || param.size() < 1){
        return "";
    }

    for(String key : param.keySet()){
        String value = param.get(key);
        if(value != null && !value.isEmpty()){
            builder.append(" and " + key + " = '" + value + "'");
        }
    }

    return new String(builder);
}

上面用到了 StringUtil.java，我们在 com.chanshuyi.util 中导入它：

package com.mszz.util;

import java.util.Collection;
import java.util.Map;

/**
 * 字符串工具类
 * @author chenxinquan
 *
 */
public class StringUtil {
    /**
     * 判断对象或对象数组中每一个对象是否为空: 对象为null，字符序列长度为0，集合类、Map为empty
     * @author zl
     * @param obj
     * @return
     */
    public static boolean isNullOrEmpty(Object obj) {
        if (obj == null)
            return true;

        if (obj instanceof CharSequence)
            return ((CharSequence) obj).length() == 0;

        if (obj instanceof Collection)
            return ((Collection) obj).isEmpty();

        if (obj instanceof Map)
            return ((Map) obj).isEmpty();

        if (obj instanceof Object[]) {
            Object[] object = (Object[]) obj;
            if (object.length == 0) {
                return true;
            }
            boolean empty = true;
            for (int i = 0; i < object.length; i++) {
                if (!isNullOrEmpty(object[i])) {
                    empty = false;
                    break;
                }
            }
            return empty;
        }
        return false;
    }
}

StringUtil.java

创建 com.chanshuyi.dao.impl.BaseDao.java 类，提供基本的数据库读写对象，并用注解方式将 SqlSession 注入。

package com.chanshuyi.dao.impl;

import org.apache.ibatis.session.SqlSession;
import org.springframework.beans.factory.annotation.Autowired;

/**
 * 所有Service的基类，用来注入sqlSession
 */
public class BaseDao {
    /**
     * 可写的sqlSession
     */
    @Autowired
    protected SqlSession writableSQLSession;

    /**
     * 只读的sqlSession
     */
    @Autowired
    protected SqlSession readonlySQLSession;
}

创建DAO层接口 IUserDao.java：

package com.chanshuyi.dao;

import com.chanshuyi.model.User;

import java.util.List;
import java.util.Map;

/**
 * Created by chanshuyi on 2015/12/26.
 */
public interface IUserDao {
    User getUserById(int userId);

    /**
     *
     * @param param Map中的key要与数据库表中的字段名相同
     * @return
     */
    User getUserByMapSql(Map<String, String> param);

    List<User> getUserListByMapSql(Map<String, String> param);
}

创建 UserDaoImpl.java 继承 BaseDao.java、实现 IUserDao 接口，并用 @Repository 创建名称为 userDao 的对象。

package com.chanshuyi.dao.impl;

import com.chanshuyi.dao.IUserDao;
import com.chanshuyi.dao.mapper.UserMapper;
import com.chanshuyi.model.User;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.stereotype.Repository;

import java.util.List;
import java.util.Map;

/**
 * Created by Administrator on 2015/12/26.
 */
@Repository("userDao")
public class UserDaoImpl extends BaseDao implements IUserDao {

    private static Log logger = LogFactory.getLog(UserDaoImpl.class);

    @Override
    public User getUserById(int userId) {
        UserMapper mapper = readonlySQLSession.getMapper(UserMapper.class);
        return mapper.selectByPrimaryKey(userId);
    }

    /**
     *
     * @param param
     * @return
     */
    @Override
    public User getUserByMapSql(Map<String, String> param) {
        logger.info("getUserByMapSql 根据动态参数查询用户对象");
        return getUserListByMapSql(param).size() > 0 ? getUserListByMapSql(param).get(0) : null;
    }

    /**
     * get**MapSql()类的方法只能用于各参数的等于查询
     * 例如：select * from user where username = 1 and password = 3  （正确）
     *       select * from user where username in (1,2,3) （错误，无法实现）
     * @param param
     * @return
     */
    @Override
    public List<User> getUserListByMapSql(Map<String, String> param) {
        logger.info("getUserListByMapSql 根据动态参数查询用户对象列表");
        UserMapper mapper = readonlySQLSession.getMapper(UserMapper.class);
        return mapper.getUserListByMapSql(param);
    }
}

创建 IUserService.java 和 UserServiceImpl.java。在 UserServiceImpl 中添加 @Service 注解创建名称为 userService 的对象，并将 userDao 对象注入。

package com.mszz.service;

import com.mszz.model.User;

import java.util.List;
import java.util.Map;

/**
 * Created by chanshuyi on 2015/12/26.
 */
public interface IUserService {
    User getUserById(int userId);

    /**
     *
     * @param param Map中的key要与数据库表中的字段名相同
     * @return
     */
    User getUserByMapSql(Map<String, String> param);

    List<User> getUserListByMapSql(Map<String, String> param);
}

package com.chanshuyi.service.impl;

import com.chanshuyi.dao.IUserDao;
import com.chanshuyi.model.User;
import com.chanshuyi.service.IUserService;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;
import java.util.Map;

/**
 * Created by Administrator on 2015/6/18.
 */
@Service("userService")
public class UserServiceImpl implements IUserService {

    private static Log logger = LogFactory.getLog(UserServiceImpl.class);

    @Autowired
    IUserDao userDao;

    @Override
    public User getUserById(int userId) {
        return userDao.getUserById(userId);
    }

    @Override
    public User getUserByMapSql(Map<String, String> param) {
        return userDao.getUserByMapSql(param);
    }

    @Override
    public List<User> getUserListByMapSql(Map<String, String> param) {
        return userDao.getUserListByMapSql(param);
    }
}

五、开发控制层（Struts）

创建 com.chanshuyi.action.UserController 类

package com.chanshuyi.controller;

import com.chanshuyi.service.IUserService;
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 org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.servlet.http.HttpServletRequest;
import java.util.HashMap;
import java.util.Map;

/**
 * Created by Administrator on 2015/6/18.
 */
@Controller("userAction")
@RequestMapping(value="/login")
public class UserController{

    private static Logger logger = LoggerFactory.getLogger(UserController.class);

    private String message;

    private String username;

    private String password;

    @Autowired
    private IUserService userService;

    @Autowired
    private HttpServletRequest request;

    @RequestMapping("")
    public String login(@RequestParam(value = "username", required = false) String username,
            @RequestParam(value = "password", required = false) String password){
        try{
            Map<String, String> param = new HashMap<String, String>();
            param.put("username", username);
            param.put("password", password);
            if(userService.getUserByMapSql(param) != null){
                message = "登录成功！";
                logger.info(message);
            }else{
                message = "登录失败！";
                logger.info(message);
            }
        }catch(Exception e){
            logger.warn(e.getMessage());
            e.printStackTrace();
        }
        request.setAttribute("message", message);
        return "index";  // 转到webapp/index.jsp页面
    }

    /******** set/get ********/
    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    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;
    }
}

创建 webapp/index.jsp 文件

<%@page language="java" pageEncoding="UTF-8"%>
<%@ page contentType="text/html;charset=utf-8" %>
<%@ page isELIgnored="false"%>
<html>
<head>
    <meta charset="utf-8">
</head>
<body>
<h2>Hello World!</h2>
<%-- 通过Struts传递参数,数据传递方式必须选择post,否则编码错误! --%>
<form action="login" method="post" >
    <p id="message">${message}</p>
    <b>Username:</b><input type="text" id="name" name="username" /><br>
    <b>Password:</b><input type="password" id="password" name="password"/><br>
    <input type="submit"  value="Login"/>
</form>
</body>
</html>

修改 web.xml 文件，加载 SpringMVC 处理器

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>

    <!-- 字符集过滤器 -->
    <filter>
        <filter-name>encodingFilter</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>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!-- spring MVC的核心就是DispatcherServlet，使用springMVC的第一步就是将下面的servlet放入web.xml
      servlet-name属性非常重要，默认情况下，DispatchServlet会加载这个名字-servlet.xml的文件，如下，就会加载
      dispather-servlet.xml，也是在WEN-INF目录下。-->
    <servlet>
        <servlet-name>spring</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:/spring-servlet.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <!-- 设置dispatchservlet的匹配模式，通过把dispatchservlet映射到/，默认servlet会处理所有的请求，包括静态资源 -->
    <servlet-mapping>
        <servlet-name>spring</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

六、启动项目测试

为工程配置 Maven 命令 “tomcat7:run” 

点击启动项目

打开浏览器输入：http://localhost:5050/index.jsp 

输入 admin/password，点击 Login 按钮

提示登录成功，说明项目已经成功部署好。

与 Spring 框架项目对比

因为我们一般用 SpringMVC 的时候都是用注解的形式，所以SpringMVC 框架的项目都是注解形式，没有 XML 配置文件方式。下面我们来对比一下用 SpringMVC 和用 Spring + Struts 的实现区别。

1、使用 SpringMVC 框架时需要配置与 Spring 不同的 web.xml 配置，并且读取的根配置文件不再是 applicationContext.xml，而是 servletName-servlet.xml（servletName 表示的是配置在 web.xml 中的servlet 名称）。

2、因为使用了 SpringMVC，所以不再需要 Struts 来接收用户请求，而是直接通过 @RequestMapping 注解的方式在 Controller 类上进行注解映射，也就少了 struts.xml 这个配置文件。而一般情况下用 SpringMVC 的项目更习惯于将 Action 写成 Controller。

链接：http://pan.baidu.com/s/1gdZgyqf 密码：vrm5