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签到天数: 15 天 [LV.4]偶尔看看III
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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。
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新建一个maven web项目,工程结构如下,并创建一个pojo类Person
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- 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;
- }
-
- }
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配置篇
1.Spring 集成Mybatis配置文件以及应用(application-root.xml + maybatis-config.xml + jsbc.properties)
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- <?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>
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- <?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>
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- 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
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2.Spring MVC配置(application-mvc.xml)
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- <?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>
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3.PersonMapper映射配置文件(personMapper.xml)
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- <?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>
- <id property="name" column="name"></id>
- <id property="gender" column="gender"></id>
- </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>
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4.web.xml配置(web.xml)
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- <?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>
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代码篇
1.mapper包下(com.mmm.mapper)
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- 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();
- }
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2.service包下(com.mmm.service)
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- 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();
- }
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- 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();
- }
-
- }
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3.web包下(com.mmm.web)
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- 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);
- }
-
-
- }
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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)
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- 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());
- }
-
- }
- }
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结果如下
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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
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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。
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