SSM框架开发web项目系列（一） 环境搭建篇

前言

　　开发环境：Eclipse Mars + Maven + JDK 1.7 + Tomcat 7 + MySQL

　　主要框架：Spring + Spring MVC + Mybatis

　　目的：快速上手搭建SSM开发环境，熟悉客户端请求到数据库操作的流程。

准备工作

　　本文以“人”Person对象为例，所以首先在数据库中建一张表。这里用的Navicat for MySql,新建一个名为ssm的数据库，然后在库中新建一张名为TBL_PERSON的表,3个字段，分别为主键id,姓名name,性别gender,都为字符串类型。这里主键id没有采用自增，而是用UUID随机字符串。数据表概要如图所示。

 

　　新建一个maven web项目，工程结构如下和pom.xml配置如下，并创建一个pojo类Person

<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.mmm</groupId>
  <artifactId>ssm-web</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>ssm-web Maven Webapp</name>
  <url>http://maven.apache.org</url>
  
    <properties>  
            <!-- spring版本号 -->  
            <spring.version>4.0.2.RELEASE</spring.version>  
            <!-- mybatis版本号 -->  
            <mybatis.version>3.2.6</mybatis.version>  
            <!-- log4j日志文件管理包版本 -->  
            <slf4j.version>1.7.7</slf4j.version>  
            <log4j.version>1.2.17</log4j.version>  
        </properties>  
      
        <dependencies>  
            <dependency>  
                <groupId>junit</groupId>  
                <artifactId>junit</artifactId>  
                <version>4.11</version>  
                <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>  
            <dependency>  
                <groupId>javax</groupId>  
                <artifactId>javaee-api</artifactId>  
                <version>7.0</version>  
            </dependency>  
            <!-- 导入Mysql数据库链接jar包 -->  
            <dependency>  
                <groupId>mysql</groupId>  
                <artifactId>mysql-connector-java</artifactId>  
                <version>5.1.30</version>  
            </dependency>  
            <dependency>  
                <groupId>commons-dbcp</groupId>  
                <artifactId>commons-dbcp</artifactId>  
                <version>1.2.2</version>  
            </dependency>  
            <!-- JSTL标签类 -->  
            <dependency>  
                <groupId>jstl</groupId>  
                <artifactId>jstl</artifactId>  
                <version>1.2</version>  
            </dependency>  
            <dependency>  
                <groupId>log4j</groupId>  
                <artifactId>log4j</artifactId>  
                <version>${log4j.version}</version>  
            </dependency>  
            <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>  
            <dependency>  
                <groupId>org.codehaus.jackson</groupId>  
                <artifactId>jackson-mapper-asl</artifactId>  
                <version>1.9.13</version>  
            </dependency>  
            <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>  
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-annotations</artifactId>
        <version>2.5.0</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>2.5.0</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.5.0</version>
    </dependency>
        </dependencies>  
  <build>
    <finalName>ssm-web</finalName>
  </build>
</project>

 

package com.mmm.pojo;
/**
 * Person实体类
 * */
public class Person {
    
    private String id;
    
    private String name;
    
    private String gender;
    
    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 String getGender() {
        return gender;
    }
    
    public void setGender(String gender) {
        this.gender = gender;
    }
    

}

配置篇

　　1.Spring 集成Mybatis配置文件以及应用（application-root.xml + maybatis-config.xml + jsbc.properties）

<?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-4.0.xsd    
                        http://www.springframework.org/schema/context    
                        http://www.springframework.org/schema/context/spring-context-4.0.xsd">  
                        
    <!-- 引入数据库配置参数文件jdbc.properties -->                
    <context:property-placeholder location="classpath:jdbc.properties"/>
    
    <!-- Spring会扫描指定包下的bean注解例如@Controller、@Service等 -->   
    <context:component-scan base-package="com.mmm" />
    
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <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>
        
    <!-- spring和MyBatis整合 -->  
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">  
        <property name="dataSource" ref="dataSource" />  
        <!-- 自动扫描mapper.xml文件 -->  
        <property name="mapperLocations" value="classpath:com/mmm/mapper/*.xml"></property>  
        <property name="configLocation" value="classpath:mybatis-config.xml"></property>
    </bean>  
  
    <!-- Mapper接口所在包名，Spring会自动查找其下的类 -->  
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">  
        <property name="basePackage" value="com.mmm.mapper" />  
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>  
    </bean>
     
</beans>

<?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>
    <!-- 这里可以定义类的别名，在mapper.xml文件中应用会方便很多 -->
    <typeAliases>
        <typeAlias alias="person" type="com.mmm.pojo.Person" />
    </typeAliases>
</configuration>

jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/ssm?characterEncoding=utf-8
jdbc.username=root
jdbc.password=123456

　　2.Spring MVC配置（application-mvc.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-4.0.xsd    
                        http://www.springframework.org/schema/context    
                        http://www.springframework.org/schema/context/spring-context-4.0.xsd    
                        http://www.springframework.org/schema/mvc    
                        http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">  
                        
     <!-- 自动扫描开启 -->
      <context:component-scan base-package="com.mmm.web" />
     <mvc:annotation-driven/>
     
     <!-- Spring MVC视图解析配置-->  
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">  
        <property name="prefix" value="/WEB-INF/views/" />  
        <property name="suffix" value=".jsp" />  
    </bean>  
                        
                        
</beans>

　　3.PersonMapper映射配置文件（personMapper.xml）

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" 
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.mmm.mapper.PersonMapper">
    
    <resultMap type="person" id="personResultMap" >
        <id property="id" column="id"></id>
        <result property="name" column="name"></result>
        <result property="gender" column="gender"></result>
    </resultMap>
    
    <!-- 新增一条记录 -->
    <insert id="insert" parameterType="person" >
        <selectKey keyProperty="id" order="BEFORE" resultType="java.lang.String">
            select replace(uuid(),'-','') from dual
        </selectKey>
        insert into `TBL_PERSON` values (#{id},#{name},#{gender})
    </insert>
    
    <!-- 删除一条记录 -->
    <delete id="delete">
        delete from `TBL_PERSON` where id = #{id}
    </delete>
    
    <!-- 更新一条记录 -->
    <update id="update" parameterType="person">
        update `TBL_PERSON` set name = #{name}, gender = #{gender}
    </update>
    
    <!-- 查找所有记录 -->
    <select id="selectAll" resultMap="personResultMap">
        select * from `TBL_PERSON`
    </select>
    
    <!-- 根据主键id查找记录 -->
    <select id="selectById" resultType="person">
        select * from `TBL_PERSON` where id = #{id}
    </select>
</mapper>

　　4.web.xml配置（web.xml）

<?xml version="1.0" encoding="UTF-8"?>  
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
    xmlns="http://java.sun.com/xml/ns/javaee"  
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"  
    version="3.0"> 
    
    <!-- Spring的配置文件 -->  
    <context-param>  
        <param-name>contextConfigLocation</param-name>  
        <param-value>classpath:application-root.xml</param-value>  
    </context-param>  
    <!-- 编码过滤器 -->  
    <filter>  
        <filter-name>encodingFilter</filter-name>  
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>  
        <async-supported>true</async-supported>  
        <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监听器 -->  
    <listener>  
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  
    </listener>  
  
    <!-- Spring MVC servlet -->  
    <servlet>  
        <servlet-name>SpringMVC</servlet-name>  
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  
        <init-param>  
            <param-name>contextConfigLocation</param-name>  
            <param-value>classpath:application-mvc.xml</param-value>  
        </init-param>  
        <load-on-startup>1</load-on-startup>  
        <async-supported>true</async-supported>  
    </servlet>  
    <servlet-mapping>  
        <servlet-name>SpringMVC</servlet-name>  
        <url-pattern>/</url-pattern>  
    </servlet-mapping>  
    
</web-app>

代码篇

　　1.mapper包下（com.mmm.mapper）

package com.mmm.mapper;

import java.util.List;

import com.mmm.pojo.Person;

public interface PersonMapper {
    //新增一个Person对象
    void insert(Person p);
    
    //根据主键id删除Person对象
    void deleteById(String id);
    
    //修改一个person对象
    void update(Person p);
    
    //根据主键id查找Person对象
    Person selectById(String id);
    
    //查找所有Person对象，返回集合类型
    List<Person> selectAll();

}

　　2.service包下（com.mmm.service）

package com.mmm.service;

import java.util.List;

import com.mmm.pojo.Person;

public interface PersonService {
    
    //新增一个Person对象
    void insert(Person p);
    
    //根据主键id删除Person对象
    void deleteById(String id);
    
    //修改一个person对象
    void update(Person p);
    
    //根据主键id查找Person对象
    Person selectById(String id);
    
    //查找所有Person对象，返回集合类型
    List<Person> selectAll();
}

package com.mmm.service;

import java.util.List;

import javax.annotation.Resource;

import org.springframework.stereotype.Service;

import com.mmm.mapper.PersonMapper;
import com.mmm.pojo.Person;
@Service
public class PersonServiceImpl implements PersonService {
    
    @Resource
    PersonMapper personMapper;

    @Override
    public void insert(Person p) {
        personMapper.insert(p);
    }

    @Override
    public void deleteById(String id) {
        personMapper.deleteById(id);
    }

    @Override
    public void update(Person p) {
        personMapper.update(p);
    }

    @Override
    public Person selectById(String id) {
        return personMapper.selectById(id);
    }

    @Override
    public List<Person> selectAll() {
        return personMapper.selectAll();
    }
    
}

　　3.web包下（com.mmm.web）

package com.mmm.web;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import com.mmm.pojo.Person;
import com.mmm.service.PersonService;

@Controller
@RequestMapping("person")
public class PersonController {
    
    @Autowired
    PersonService personService;
    
    /**
     * 这里return的字符串"mvc"加上前面Spring MVC配置文件中视图解析配置的前缀"/WEB-INF/views/"和后缀".jsp",
     * 构成了要请求转发要跳转到的页面路径，从根路径webapp下开始，即为/WEB-INF/views/mvc.jsp
     * */
    @RequestMapping(value="mvc")
    public String testMvc() {
        return "mvc";//
    }
    
    /**
     * 这里@ResponseBody代表方法是直接返回一个json数据回前端，
     * 注意Spring mvc配置文件中不要漏掉<mvc:annotation-driven/>
     * */
    @RequestMapping(value="list")
    @ResponseBody
    public List<Person> findAll() {
        List<Person> list = personService.selectAll();
        return list;//这里通过前端返回的json数据查看到完整数据
    } 
    
    /**
     * 其中@PathVariable用来获得请求url中的动态参数
     * */
    @RequestMapping(value="one/{id}")
    @ResponseBody
    public Person findOne(@PathVariable("id") String id) {
        return personService.selectById(id);
    }
    
    
}

 　　至此，ssm开发基本环境已经初步搭建好

测试篇

　　1.测试mybatis封装的持久层（这里以获取所有TBL_PERSON表的NAME字段值为例）

package com.test;

import java.util.List;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.mmm.pojo.Person;
import com.mmm.service.PersonService;

public class TestDb {
    @SuppressWarnings("resource")
    @Test
    public void testDb() {
        ApplicationContext context = new ClassPathXmlApplicationContext("application-root.xml");
        PersonService bean = (PersonService) context.getBean("personServiceImpl");
        List<Person> list = bean.selectAll();
        for(Person p:list) {
            System.out.println(p.getName());
        }
        
    }
}

结果如下

　　2.测试Spring MVC部分

 　 Tomcat启动项目，地址栏输入http://localhost:8080/ssm-web/person/list,拿到如下图所示数据即为成功

 反省篇

　　最后，SSM开发环境基本搭建完毕，既然是基本，还存在许多没有尽量完善的地方。首先Mybatis部分，这里是从零开始，也没用到什么逆向工程之类的，都自己手写，便于理解，然后关联映射只写了简单的单表操作，关联的没写到，另外单表简单操作，在这里与spring集成过程中事务也没有进行事务管理的配置等。Spring MVC方面更是简陋了点，不过实际工作开发中，比较核心的有视图解析后转发到相应页面和json返回数据，大多问题是在考虑怎样实现业务逻辑。很多细节没有写出来，然后有些原理性的东西自己也还需要不断理解学习，之后应该写一些关键细节描述类的总结文。