SSM: Spring + Spring MVC + MyBatis
Spring:Spring是一个开源框架,Spring是于2003 年兴起的一个轻量级的Java 开发框架,由Rod Johnson 在其著作Expert One-On-One J2EE Development and Design中阐述的部分理念和原型衍生而来。它是为了解决企业应用开发的复杂性而创建的。Spring使用基本的JavaBean来完成以前只可能由EJB完成的事情。然而,Spring的用途不仅限于服务器端的开发。从简单性、可测试性和松耦合的角度而言,任何Java应用都可以从Spring中受益。 简单来说,Spring是一个轻量级的控制反转(IoC)和面向切面(AOP)的容器框架。
Spring MVC: Spring MVC属于SpringFrameWork的后续产品,已经融合在Spring Web Flow里面。Spring MVC 分离了控制器、模型对象、分派器以及处理程序对象的角色,这种分离让它们更容易进行定制。
MyBatis: MyBatis 本是apache的一个开源项目iBatis, 2010年这个项目由apache software foundation 迁移到了google code,并且改名为MyBatis 。MyBatis是一个基于Java的持久层框架。iBATIS提供的持久层框架包括SQL Maps和Data Access Objects(DAO)MyBatis 消除了几乎所有的JDBC代码和参数的手工设置以及结果集的检索。MyBatis 使用简单的 XML或注解用于配置和原始映射,将接口和 Java 的POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录。
创建javaWeb项目,导入jar包(此处为非Maven项目)
配置相关文件
MyBatis配置文件
mybatis.cfg.xml
在该配置文件中,主要需要配置实体映射文件(也可以在applicationContext.xml中扫描引入,基于注解则不需要),也可以设置别名(主要是配置typeAlias,将实体类匹配成XXXMapper.xml中可以直接使用的类型,相当于一个别名,在XXXMapper.xml中就无需再写完整的实体类全路径,直接用alias的值来代替。)
<?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>
<mapper resource="com/ssm/mapper/EmployeeMapper.xml"/>
</mappers>
</configuration>
Spring配置文件
applicationContext.xml
在该配置文件中,主要需要配置数据源,整合mybatis,Dao接口的扫描以及事务管理等,示例如下:
<?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:aop="http://www.springframework.org/schema/aop"
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-4.3.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.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">
<!-- 加载jdbc.properties文件 -->
<context:property-placeholder location="classpath:jdbc.properties" />
<!-- 数据源 -->
<bean id="dataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${jdbc.driver}"></property>
<property name="url" value="${jdbc.url}"></property>
<property name="username" value="${jdbc.username}"></property>
<property name="password" value="${jdbc.password}"></property>
</bean>
<!--Spring 完美整合MyBatis -->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="configLocation" value="classpath:mybatis.cfg.xml"></property>
<property name="dataSource" ref="dataSource"></property>
</bean>
<!-- DAO接口所在包名,Spring会自动查找之中的类 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.ssm.dao" />
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>
</bean>
<!--事务管理,非必须 -->
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<!--注入dataSource -->
<property name="dataSource" ref="dataSource" />
</bean>
<!--开启事务注解扫描 -->
<tx:annotation-driven transaction-manager="transactionManager"></tx:annotation-driven>
</beans>
springmvc-servlet.xml
在该配置文件中,主要需要启用注解驱动,扫描包,配置视图解析器以及对静态资源访问的相关配置等。
<?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:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
<!-- 启用注解驱动 -->
<mvc:annotation-driven />
<!-- org.springframework.web.servlet.resource.DefaultServletHttpRequestHandler,
它会对进入DispatcherServlet的URL进行筛查,如果发现是静态资源的请求, 就将该请求转由Web应用服务器默认的Servlet处理,如果不是静态资源的请求,才由DispatcherServlet继续处理。 -->
<mvc:default-servlet-handler />
<!-- 扫描包 -->
<context:component-scan base-package="com.ssm" />
<!-- 对静态资源文件的访问,因为Spring MVC会拦截所有请求,导致jsp页面中对js和CSS的引用也被拦截,配置后可以把对资源的请求交给项目的
默认拦截器而不是Spring MVC -->
<mvc:resources mapping="/static/**" location="/WEB-INF/static/" />
<!-- 对模型视图名称的解析,即在模型视图名称添加前后缀 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/"></property>
<property name="suffix" value=".jsp"></property>
</bean>
</beans>
web.xml
在该配置文件中,主要需要加载Spring配置,并且需要将所有请求交给Spring MVC来处理,还可以设置编码过滤器等。
<?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">
<display-name>SSM</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<!--1. 告诉Web容器,将加载启动Spring bean实例化 -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:applicationContext.xml</param-value>
</context-param>
<!-- 2 配置整合SPring MVC -->
<servlet>
<servlet-name>MyDispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<!-- 加载配置文件路径 -->
<!-- contextConfigLocation:指定springmvc配置的加载位置,如果不指定则默认加载WEB-INF/[DispatcherServlet 的Servlet 名字]-servlet.xml。 -->
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:springmvc-servlet.xml</param-value>
</init-param>
<!-- <param-value>classpath:spring*.xml</param-value> -->
<!-- 何时启动 大于0的值表示容器启动时初始化此servlet,正值越小优先级越高 -->
<load-on-startup>1</load-on-startup>
</servlet>
<!-- Spring MVC配置文件结束 -->
<!-- SpringMVC拦截设置 -->
<servlet-mapping>
<servlet-name>MyDispatcher</servlet-name>
<!-- 由SpringMVC拦截所有请求 -->
<!-- url-pattern:/的请交给DispatcherServlet处理。 -->
<url-pattern>/</url-pattern>
</servlet-mapping>
<!-- SpringMVC拦截设置结束 -->
<!-- 设置编码过滤器 -->
<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>
</web-app>
jdbc.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/ssm?useUnicode=true&characterEncoding=utf8
jdbc.username=root
jdbc.password=
log4j.properties(非必须)
log4j.properties
### set log levels ###
log4j.rootLogger = INFO , console , debug , error
### console ###
log4j.appender.console = org.apache.log4j.ConsoleAppender
log4j.appender.console.Target = System.out
log4j.appender.console.layout = org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern = %-d{yyyy-MM-dd HH\:mm\:ss} [%p]-[%c] %m%n
### log file ###
log4j.appender.debug = org.apache.log4j.DailyRollingFileAppender
log4j.appender.debug.File = ../logs/ssm-demo.log
log4j.appender.debug.Append = true
log4j.appender.debug.Threshold = INFO
log4j.appender.debug.layout = org.apache.log4j.PatternLayout
log4j.appender.debug.layout.ConversionPattern = %-d{yyyy-MM-dd HH\:mm\:ss} [%p]-[%c] %m%n
### exception ###
log4j.appender.error = org.apache.log4j.DailyRollingFileAppender
log4j.appender.error.File = ../logs/ssm-demo_error.log
log4j.appender.error.Append = true
log4j.appender.error.Threshold = ERROR
log4j.appender.error.layout = org.apache.log4j.PatternLayout
log4j.appender.error.layout.ConversionPattern = %-d{yyyy-MM-dd HH\:mm\:ss} [%p]-[%c] %m%n
###\u9700\u8981\u58F0\u660E\uFF0C\u7136\u540E\u4E0B\u65B9\u624D\u53EF\u4EE5\u4F7Fdruid sql\u8F93\u51FA\uFF0C\u5426\u5219\u4F1A\u629B\u51FAlog4j.error.key not found
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ISO8601} %l %c%n%p: %m%n
### druid sql ###
log4j.logger.druid.sql=warn,stdout
log4j.logger.druid.sql.DataSource=warn,stdout
log4j.logger.druid.sql.Connection=warn,stdout
log4j.logger.druid.sql.Statement=warn,stdout
log4j.logger.druid.sql.ResultSet=warn,stdout
其他文件
Employee.java
package com.ssm.model;
public class Employee {
private int empId;
private String empName;
private int empAge;
private String empSex;
public Employee() {
super();
}
public int getEmpId() {
return empId;
}
public void setEmpId(int empId) {
this.empId = empId;
}
public String getEmpName() {
return empName;
}
public void setEmpName(String empName) {
this.empName = empName;
}
public int getEmpAge() {
return empAge;
}
public void setEmpAge(int empAge) {
this.empAge = empAge;
}
public String getEmpSex() {
return empSex;
}
public void setEmpSex(String empSex) {
this.empSex = empSex;
}
@Override
public String toString() {
return "Employee [empId=" + empId + ", empName=" + empName + ", empAge=" + empAge + ", empSex=" + empSex + "]";
}
}
IEmployeeDao.java
package com.ssm.dao;
import java.util.List;
import org.springframework.stereotype.Repository;
import com.ssm.model.Employee;
@Repository("empDao")
public interface IEmployeeDao {
public List<Employee> selectAll();
}
EmployeeMapper.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.ssm.dao.IEmployeeDao">
<resultMap id="allEmp" type="com.ssm.model.Employee" >
<id property="empId" column="empId" />
<result property="empName" column="empName"/>
<result property="empAge" column="empAge"/>
<result property="empSex" column="empSex"/>
</resultMap>
<!-- 查询所有员工 -->
<select id="selectAll" resultType="com.ssm.model.Employee">
SELECT * FROM tb_emp;
</select>
</mapper>
EmployeeServiceImpl.java
package com.ssm.service;
import java.util.List;
import javax.annotation.Resource;
import org.springframework.stereotype.Service;
import com.ssm.dao.IEmployeeDao;
import com.ssm.model.Employee;
@Service(value="employeeService")
public class EmployeeServiceImpl implements IEmployeeService {
@Resource(name="empDao")
private IEmployeeDao empDao;
@Override
public List<Employee> showAll() {
// TODO Auto-generated method stub
return this.empDao.selectAll();
}
}
EmpController.java
package com.ssm.controller;
import java.util.List;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import com.ssm.model.Employee;
import com.ssm.service.IEmployeeService;
@Controller
public class EmpController {
//@Autowired
@Resource(name="employeeService")
private IEmployeeService employeeService;
@RequestMapping("/toShowAll")
public String toShowAll(HttpServletRequest request) {
List<Employee> emps = this.employeeService.showAll();
System.out.println("查询所有:"+emps.size());
request.setAttribute("EMPS", emps);
return "show";
}
public String deleteEmp(HttpServletRequest request) {
return null;
}
}