ssm框架搭建

1、前言

SSM框架在项目开发中经常使用到，相比于SSH框架，它在仅几年的开发中运用的更加广泛。

• Spring作为一个轻量级的框架，有很多的拓展功能，最主要的我们一般项目使用的就是IOC和AOP。
• SpringMVC是Spring实现的一个Web层，相当于Struts的框架，但是比Struts更加灵活和强大！
• Mybatis是 一个持久层的框架，在使用上相比Hibernate更加灵活，可以控制sql的编写，使用 XML或注解进行相关的配置！

2、框架搭建概述

准备工作：

• STS编译器，这个一个集成了spring环境的eclicpse，可以在spring的官网去下载。
• maven创建的Javaweb工程

3、框架搭建

3.1 ssm搭建完成整体架构

3.2 maven依赖注入

这里只注入一些ssm框架需要的基本jar，后需需要更多功能需求的可自行添加。
数据库连接池这里使用的是C3P0连接池
注意：spring和springmvc的版本要一致，mybatis版本要选能与spring兼容的版本，关于版本我在网上也没有找到有效的答案，只能多去试几个版本。

	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-context</artifactId>
		<version>5.0.6.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-web</artifactId>
		<version>5.0.6.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-webmvc</artifactId>
		<version>5.0.6.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>commons-logging</groupId>
		<artifactId>commons-logging-api</artifactId>
		<version>1.1</version>
	</dependency>
	<dependency>
		<groupId>log4j</groupId>
		<artifactId>log4j</artifactId>
		<version>1.2.12</version>
	</dependency>
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-tx</artifactId>
		<version>5.0.6.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>org.apache.taglibs</groupId>
		<artifactId>taglibs-standard-impl</artifactId>
		<version>1.2.5</version>
	</dependency>
	<dependency>
		<groupId>javax.servlet</groupId>
		<artifactId>javax.servlet-api</artifactId>
		<version>3.1.0</version>
	</dependency>
	<dependency>
		<groupId>javax.servlet.jsp</groupId>
		<artifactId>jsp-api</artifactId>
		<version>2.2</version>
	</dependency>
	<dependency>
		<groupId>javax.servlet.jsp.jstl</groupId>
		<artifactId>jstl</artifactId>
		<version>1.2</version>
	</dependency>
	<dependency>
		<groupId>org.mybatis</groupId>
		<artifactId>mybatis</artifactId>
		<version>3.4.5</version>
	</dependency>
	<dependency>
		<groupId>org.mybatis</groupId>
		<artifactId>mybatis-spring</artifactId>
		<version>2.0.0</version>
	</dependency>
	<dependency>
		<groupId>com.mchange</groupId>
		<artifactId>c3p0</artifactId>
		<version>0.9.5.2</version>
	</dependency>
	<dependency>
		<groupId>mysql</groupId>
		<artifactId>mysql-connector-java</artifactId>
		<version>5.0.7</version>
	</dependency>
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-orm</artifactId>
		<version>5.0.6.RELEASE</version>
	</dependency>

3.2 创建工程的包目录及测试所需类

这一步把mvc模式下所需的包和用来测试的类都写好，有DAO层、model层、service层、controller层，图中Mapper包及对应的DAO层

3.3 配置springmvc

在文件夹下创建springmvc的配置文件

<?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/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd
		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-4.3.xsd">
	
	<mvc:annotation-driven />
	<!-- 注解包扫描，只扫描controller层下的注解 -->
	<context:component-scan
		base-package="com.wfq.ssm.controller" />

	<!-- 视图解析器 -->
	<bean id="internalResourceViewResolver"
		class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<!-- 访问路径前缀 -->
		<property name="prefix" value="/WEB-INF/jsp/" />
		<!-- 访问路径前缀 -->
		<property name="suffix" value=".jsp" />
	</bean>
</beans>

3.4 创建数据库连接信息文件和log4j日志文件

jdbc.properties：

jdbc.user=root
jdbc.password=root
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc:mysql://localhost:3306/spring

log4j.properties：

log4j.rootLogger=INFO,Console,File  
#\u5B9A\u4E49\u65E5\u5FD7\u8F93\u51FA\u76EE\u7684\u5730\u4E3A\u63A7\u5236\u53F0  
log4j.appender.Console=org.apache.log4j.ConsoleAppender  
log4j.appender.Console.Target=System.out  
#\u53EF\u4EE5\u7075\u6D3B\u5730\u6307\u5B9A\u65E5\u5FD7\u8F93\u51FA\u683C\u5F0F\uFF0C\u4E0B\u9762\u4E00\u884C\u662F\u6307\u5B9A\u5177\u4F53\u7684\u683C\u5F0F  
log4j.appender.Console.layout = org.apache.log4j.PatternLayout  
log4j.appender.Console.layout.ConversionPattern=[%c] - %m%n  
  
#\u6587\u4EF6\u5927\u5C0F\u5230\u8FBE\u6307\u5B9A\u5C3A\u5BF8\u7684\u65F6\u5019\u4EA7\u751F\u4E00\u4E2A\u65B0\u7684\u6587\u4EF6  
log4j.appender.File = org.apache.log4j.RollingFileAppender  
#\u6307\u5B9A\u8F93\u51FA\u76EE\u5F55  
log4j.appender.File.File = logs/ssm.log  
#\u5B9A\u4E49\u6587\u4EF6\u6700\u5927\u5927\u5C0F  
log4j.appender.File.MaxFileSize = 10MB  
# \u8F93\u51FA\u6240\u4EE5\u65E5\u5FD7\uFF0C\u5982\u679C\u6362\u6210DEBUG\u8868\u793A\u8F93\u51FADEBUG\u4EE5\u4E0A\u7EA7\u522B\u65E5\u5FD7  
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  

3.5 配置spring

创建 applicationContext.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: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-4.3.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.3.xsd">

	<!-- 注解扫描 -->
	<context:component-scan
		base-package="com.wfq.ssm">
		<!-- 不扫描controller包下的注解，这是springmvc的事 -->
		<context:exclude-filter type="annotation"
			expression="org.springframework.stereotype.Controller" />
	</context:component-scan>
</beans>

3.6 整合spring和mybatis

这步是要在spring配置文件applicationContext.xml中完成的

3.6.1 创建mapper文件夹

在 classpath 路径下创建mapper文件，这里要存放每个DAO层接口对应的实现mybatis文件

3.6.2 applicationContext.xml中整合mybatis

<?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: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-4.3.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.3.xsd">

	<!-- 注解扫描 -->
	<context:component-scan
		base-package="com.wfq.ssm">
		<!-- 不扫描controller包下的注解，这是springmvc的事 -->
		<context:exclude-filter type="annotation"
			expression="org.springframework.stereotype.Controller" />
	</context:component-scan>

	<!-- 导入jdbc.properties -->
	<context:property-placeholder
		location="classpath:jdbc.properties" />
		
	<!-- 配置c3p0数据源 -->
	<bean id="dataSource"
		class="com.mchange.v2.c3p0.ComboPooledDataSource">
		<property name="user" value="${jdbc.user}"></property>
		<property name="password" value="${jdbc.password}"></property>
		<property name="driverClass" value="${jdbc.driverClass}"></property>
		<property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
	</bean>

	<!-- spring与mybaits整合 -->
	<bean id="sqlSessionFactoryBean"
		class="org.mybatis.spring.SqlSessionFactoryBean">
		<property name="dataSource" ref="dataSource"></property>
		<!-- 该属性值为存放 mybatis中mapper文件的位置 -->
		<property name="mapperLocations"
			value="classpath:mapper/*.xml"></property>
	</bean>

	<!-- mapper文件对应的dao -->
	<bean id="mapperScannerConfigurer"
		class="org.mybatis.spring.mapper.MapperScannerConfigurer">
		<!-- 该属性值为mapper文件对应的DAO层包路径 -->
		<property name="basePackage" value="com.wfq.ssm.mapper"></property>
		<property name="sqlSessionFactoryBeanName"
			value="sqlSessionFactoryBean"></property>
	</bean>

	<!-- 开启事务 -->
	<bean id="transactionManager"
		class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
		<property name="dataSource" ref="dataSource" />
	</bean>

	<!-- 开启事务注解 -->
	<tx:annotation-driven
		transaction-manager="transactionManager" />
</beans>

3.7 web.xml中注册spring和springmvc前端控制器

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">

	<!-- 启动spring容器 -->
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>classpath:applicationContext.xml</param-value>
	</context-param>
	<listener>
		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
	</listener>

	<!-- 配置springmvc前端控制器 -->
	<servlet>
		<servlet-name>springDispatcherServlet</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<init-param>
			<param-name>contextConfigLocation</param-name>
			<param-value>classpath:springmvc.xml</param-value>
		</init-param>
		<load-on-startup>1</load-on-startup>
	</servlet>
	<servlet-mapping>
		<servlet-name>springDispatcherServlet</servlet-name>
		<url-pattern>/</url-pattern>
	</servlet-mapping>

</web-app>  

到这里呢ssm框架的搭建就完了，接下来连编码，走一下mvc的完整流程，测试一下ssm是否搭建成功

4、测试

编写程序，从数据库中获取所有用户的信息，在前端页面中展示

4.1 model层

@Component
public class User {

	private int id;
	private String username;
	private String password;
	
	public User() {
		super();
		System.out.println("User被实例化");
	}
	
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	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;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", username=" + username + ", password=" + password + "]";
	}
}

4.2 dao层

public interface UserMapper {
	
	public List<User> getAllUser();

}

4.3 service层

@Service("userService")
public class UserService {

	@Resource(name="userMapper")
	UserMapper userMapper;
	
	public List<User> getAllUser(){
		return userMapper.getAllUser();
	}
	
}

4.4 controller层

@Controller
public class UserController {

	@Resource(name="userService")
	UserService userService;
	
	/*
	 * 查询所有用户
	 */
	@RequestMapping(value="/users",method=RequestMethod.GET)
	public String index(Model model) {
		List<User> users = userService.getAllUser();
		model.addAttribute("users", users);
		return "users";
	}
	
}

4.5 UserMapper.xml中写入sql

<?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>标签用来使该xml文件与接口对应，'namespace'属性的参数应该是与xml文件相对应的接口的类路径，本例中就是我们第5步所写的'userMapper'接口 -->
<mapper namespace="com.wfq.ssm.mapper.UserMapper">

	<select id="getAllUser" resultType="com.wfq.ssm.model.User">
		select * from user
	</select>

</mapper>

4.6 jsp页面

<%@ 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>
<html>
<head>
<meta charset="ISO-8859-1">
<title>获取全部用户信息</title>
</head>
<body>
	<table border="1" >
		<tr>
			<th>编号</th>
			<th>用户名</th>
			<th>密码</th>
		</tr>
		<c:forEach var="user" items="${requestScope.users }" >
			<tr>
				<td>${user.id }</td>
				<td>${user.username }</td>
				<td>${user.password }</td>
			</tr>
		</c:forEach>
	</table>
	
</body>
</html>

4.7测试成功

5、搭建过程中需要注意的问题

• spring与springmvc版本要一致
• mybatis版本要与spring兼容，这个问题我在网上没找到有效的答案，只能通过一个一个去试，有好方法的小伙伴可以在下面留言板知道一下
• mybatis的dao层实现文件mapper尽量要放在资源路径下（classpath），在学mybatis时，mapper是可以放在dao层包下，但是ssm中这种我不懂怎么去配置，有懂的朋友在留言板中知道一下。