ssm框架重写

发布于 2017年04月08日

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之前的比较粗糙，有点乱贴代码的感觉。所以重写一篇2.0版本

ssm集成步骤

1. 创建maven项目
2. 添加依赖
3. 添加/修改配置文件
4. 添加各包
5. 编写类
6. 测试

创建maven项目

创建archetype 为 webapp的maven项目

添加依赖

在pom.xml文件中添加以下依赖

<!-- junit --><dependency>    <groupId>junit</groupId>    <artifactId>junit</artifactId>    <version>4.11</version></dependency><!-- java ee --><dependency>    <groupId>javax</groupId>    <artifactId>javaee-web-api</artifactId>    <version>7.0</version></dependency><!-- jstl --><dependency>    <groupId>jstl</groupId>    <artifactId>jstl</artifactId>    <version>1.2</version></dependency><!-- mysql --><dependency>    <groupId>mysql</groupId>    <artifactId>mysql-connector-java</artifactId>    <version>5.1.12</version></dependency><!-- c3p0 --><dependency>    <groupId>c3p0</groupId>    <artifactId>c3p0</artifactId>    <version>0.9.1</version></dependency><!-- spring web --><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-web</artifactId>    <version>${spring.version}</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-webmvc</artifactId>    <version>${spring.version}</version></dependency><!-- spring core --><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-context</artifactId>    <version>${spring.version}</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-core</artifactId>    <version>${spring.version}</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-beans</artifactId>    <version>${spring.version}</version></dependency><!-- spring expression --><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-expression</artifactId>    <version>${spring.version}</version></dependency><!-- spring test --><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-test</artifactId>    <version>${spring.version}</version></dependency><!-- spring jdbc --><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-jdbc</artifactId>    <version>${spring.version}</version></dependency><!-- spring transaction --><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-tx</artifactId>    <version>${spring.version}</version></dependency><!-- mybatis --><dependency>    <groupId>org.mybatis</groupId>    <artifactId>mybatis</artifactId>    <version>3.4.1</version></dependency><dependency>    <groupId>org.mybatis</groupId>    <artifactId>mybatis-spring</artifactId>    <version>1.3.0</version></dependency>

添加/修改配置文件

先贴一张配置文件结构图

1. 修改web.xml

maven创建的web项目的web.xml的版本为2.3（关系到servlet的版本），需要改成高版本。

需要加入spring的servlet 和 spring 提供的编码filter，如下

<?xml version="1.0" encoding="UTF-8"?><web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee                      http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"version="3.1" metadata-complete="true"><!-- spring的servlet，对所有请求进行处理 --><servlet><servlet-name>dispatcherServlet</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><init-param><param-name>contextConfigLocation</param-name><param-value>classpath:spring/spring-*.xml</param-value></init-param><load-on-startup>1</load-on-startup></servlet><servlet-mapping><servlet-name>dispatcherServlet</servlet-name><url-pattern>/</url-pattern></servlet-mapping><!-- spring提供的字符集编码处理拦截器 --><filter><filter-name>characterEncodingFilter</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>characterEncodingFilter</filter-name><url-pattern>/*</url-pattern></filter-mapping><display-name>ssm</display-name></web-app>

2.添加jdbc配置文件

在resources源文件夹下创建jdbc.properties，加入以下内容

jdbc.driverClass=com.mysql.jdbc.Driverjdbc.url=jdbc:mysql://localhost:3306/ssmjdbc.username=rootjdbc.password=2292jdbc.maxPoolSize=20jdbc.maxIdleTime=1800

3.添加mybatis配置文件

在resources源文件下创建mybatis-config.xml，加入下面内容

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd"><configuration>    <settings>      <setting name="useGeneratedKeys" value="true"/>    </settings>        <!-- 别名的定义 -->    <typeAliases>        <!-- 批量定义别名 ，指定包名，自动扫描包中的类，别名即为类名，首字母大小写无所谓 -->        <package name="me.paul.ssm.entity" />    </typeAliases>    <mappers>        <!-- 通过扫描包的方式来进行批量加载映射文件 -->        <package name="me.paul.ssm.mapper" />    </mappers></configuration>

4.添加spring配置文件组

在配置web.xml文件时，设置了spring配置文件的路径为classpath:spring/spring-*.xml，所以在resources源文件夹下创建spring目录，并在里面添加名为spring-xxx.xml的配置文件。

从靠近数据库的开始，依次为 spring-dao.xml spring-tx.xml spring-service.xml spring-web.xml

spring-dao.xml 

与jdbc和mybatis相关的配置

<?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-2.5.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">    <!-- 引入配置文件 -->    <context:property-placeholder location="classpath:jdbc.properties"/>    <!-- 配置数据库连接池对象 -->    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">        <property name="driverClass" value="${jdbc.driverClass}" />        <property name="jdbcUrl" value="${jdbc.url}" />        <property name="user" value="${jdbc.username}" />        <property name="password" value="${jdbc.password}" />        <property name="maxPoolSize" value="${jdbc.maxPoolSize}" />        <property name="maxIdleTime" value="${jdbc.maxIdleTime}" />    </bean>        <!-- mybatis的session工厂 -->    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">        <property name="dataSource" ref="dataSource" />        <!-- 指定mybatis的配置文件 -->        <property name="configLocation" value="classpath:mybatis-config.xml" />    </bean>        <!-- 配置自动扫描mapper接口的包 -->    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">        <property name="basePackage" value="me.paul.ssm.mapper" />        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" />    </bean></beans>

spring-tx.xml

配置spring的事务管理器

<?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:tx="http://www.springframework.org/schema/tx"    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    http://www.springframework.org/schema/tx    http://www.springframework.org/schema/tx/spring-tx.xsd">        <!-- transactionManager -->    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">      <property name="dataSource" ref="dataSource"/>    </bean>        <!-- 通过annotation（@Transactional）来使用spring提供的transactionManager -->    <tx:annotation-driven transaction-manager="transactionManager"/>    </beans>

spring-service.xml

配置在什么包下搜索service

<?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    http://www.springframework.org/schema/tx    http://www.springframework.org/schema/tx/spring-tx.xsd">        <!-- 配置搜索service的包 -->    <context:component-scan base-package="me.paul.ssm.service"/>      </beans>

spring-web.xml

spring mvc 相关的配置

<?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"     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    http://www.springframework.org/schema/mvc    http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">        <!--         配置静态资源的实际路径及其访问路径        如        /index.html  可以访问到项目中/WEB-INF/static/index.html文件         -->    <mvc:resources location="/WEB-INF/static/" mapping="/**" />        <!-- 注解驱动，即@Controller，@RequestMapping等注解 -->    <mvc:annotation-driven />        <!-- 扫描Controller的位置 -->    <context:component-scan base-package="me.paul.ssm.controller"/>        <!--         配置视图位置，配合Controller方法中的返回值，定位到对应的jsp文件         如：            Controller 中返回字符串index            则会用以下配置的前缀（prefix）和后缀（suffix）拼接成目标路径            即，/WEB-INF/jsp/index.jsp        -->    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">        <property name="prefix" value="/WEB-INF/jsp/" />        <property name="suffix" value=".jsp" />    </bean>        </beans>

添加各包

me.paul.ssm.controller ： Controller所在包

me.paul.ssm.entity ： 实体类所在包

me.paul.ssm.mapper ： mybatis Mapper所在包，在resources源文件夹下也要创建一个这个包，用来放置mapper对应的配置文件

me.paul.ssm.service ：放置Service接口

me.paul.ssm.service.impl ： Service接口的实现

编写类

在编写类之前应添加一个数据表在对应的数据库中

mysql> show tables;+---------------+| Tables_in_ssm |+---------------+| user          |+---------------+1 row in set (0.00 sec)

表结构

mysql> desc user;+-------+-------------+------+-----+---------+----------------+| Field | Type        | Null | Key | Default | Extra          |+-------+-------------+------+-----+---------+----------------+| id    | int(11)     | NO   | PRI | NULL    | auto_increment || name  | varchar(30) | NO   | UNI | NULL    |                || age   | int(8)      | NO   |     | NULL    |                |+-------+-------------+------+-----+---------+----------------+3 rows in set (0.00 sec)

User.java

package me.paul.ssm.entity;public class User {private int id;private String name;private int age;                /*        省略getter setter        */@Overridepublic String toString() {return "User [id=" + id + ", name=" + name + ", age=" + age + "]";}}

UserMapper.java

package me.paul.ssm.mapper;import me.paul.ssm.entity.User;public interface UserMapper {void save(User user);User get(int id);}

对应的UserMapper.xml配置文件（路径是resouces下的me/paul/ssm/mapper/UserMapper.xml）

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><!-- namespace用来定位这个配置文件是和哪个接口向对应的 --><mapper namespace="me.paul.ssm.mapper.UserMapper">    <!-- useGeneratedKeys="true" 会在插入数据库后将生成的主键保存到参数对象的对应属性中，这里是id，要指定keyProperty和keyColumn -->    <insert id="save" parameterType="User" useGeneratedKeys="true" keyProperty="id" keyColumn="id">      <!--         #{name} 来获取参数对象中的name属性        如果参数时基本类型，            如 save(String name,int age)            对应的SQL写成            insert into user(name,age) values(#{0},#{1})      -->      insert into user(name,age) values(#{name},#{age})    </insert>        <select id="get" parameterType="int" resultType="User">      select * from user where id=#{0}    </select></mapper>

UserService.java

package me.paul.ssm.service;import me.paul.ssm.entity.User;public interface UserService {void save(User user);User get(int id);        //用来测试transactionManagervoid tranSave(User u1,User u2);}

UserServiceImpl.java

package me.paul.ssm.service.impl;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import org.springframework.transaction.annotation.Transactional;import me.paul.ssm.entity.User;import me.paul.ssm.mapper.UserMapper;import me.paul.ssm.service.UserService;@Servicepublic class UserServiceImpl implements UserService{        //默认根据类型自动从IOC中得到实例@Autowiredprivate UserMapper userMapper;@Overridepublic void save(User user) {userMapper.save(user);}@Overridepublic User get(int id) {return userMapper.get(id);}@Transactional@Overridepublic void tranSave(User u1, User u2) {userMapper.save(u1);userMapper.save(u2);}}

UserController.java

package me.paul.ssm.controller;import java.io.IOException;import java.io.Writer;import me.paul.ssm.entity.User;import me.paul.ssm.service.UserService;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Controller;import org.springframework.ui.Model;import org.springframework.web.bind.annotation.ModelAttribute;import org.springframework.web.bind.annotation.PathVariable;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;@Controller@RequestMapping(path="/user")public class UserController {@Autowiredprivate UserService userService;@RequestMapping(path="/save",method=RequestMethod.GET)public String save(Model model,@ModelAttribute() User user){userService.save(user);model.addAttribute("generatedKey", user.getId());return "index";}@RequestMapping(path="/get/{id}",method=RequestMethod.GET)public String get(@PathVariable("id") int id,Writer writer) throws IOException{User user = userService.get(id);writer.write(user.toString());return null;}}

index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%><%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %><!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>Index</title></head><body><h1>GeneratedKey : <c:out value="${generatedKey }"/></h1></body></html>

测试

有两个路径

localhost:8080/ssm/user/save?name=Paul&age=18   会调用UserController的save方法，添加一个元组到数据表中，并将生成的主键添加到model中，返回到index.jsp，index.jsp会将这个主键显示出来（展示useGeneratedKeys的用法）localhost:8080/ssm/user/get/5    后面的数字是用户的id，会调用UserController的get方法，得到id为5的元组并写到response的数据流中

查询数据库

mysql> select * from user;+----+------+-----+| id | name | age |+----+------+-----+|  9 | Paul |  18 |+----+------+-----+1 row in set (0.00 sec)mysql>

集成JUnit和spring

测试mapper和service的功能时懒得部署到tomcat，配置JUnit进行单元测试是个不错的选择

以上是包结构

BaseTest.java

BaseTest作为基类，先做了集成Spring所要的工作

package me.paul.ssm;import org.junit.Test;import org.junit.runner.RunWith;import org.springframework.test.context.ContextConfiguration;import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;@RunWith(SpringJUnit4ClassRunner.class)@ContextConfiguration({"classpath:spring/spring-dao.xml","classpath:spring/spring-tx.xml","classpath:spring/spring-service.xml"})public class BaseTest {        //只是为了避免在maven打包时的测试错误@Testpublic void testEmpty(){}}

UserServiceImplTest.java

package me.paul.ssm.service.impl;import org.junit.Test;import org.springframework.beans.factory.annotation.Autowired;import me.paul.ssm.BaseTest;import me.paul.ssm.entity.User;import me.paul.ssm.service.UserService;public class UserServiceImplTest extends BaseTest{@Autowiredprivate UserService userService;@Testpublic void testTranSave(){User u1 = new User();u1.setName("David");u1.setAge(29);userService.tranSave(u1,u1);}}

testTranSave方法测试了@Transactional的作用，当保存两个相同名字为David的对象时，第二个保存时出错（name字段有unique约束），第一个保存成功的也会被rollback。

这个例子的github地址：[e-mail]:gh-paulwen/ssm.git

也可以直接点击下载：ssm.rar

A man cannot whistle and drink at the same time.