java ssm框架入门（一）面向接口编程

因为工作上用到spring + strtus2 + mybatis ,所以开始学习下这个框架。

这里用到的是MySQL数据库

首先从web.xml 开始

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4"
    xmlns="http://java.sun.com/xml/ns/j2ee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
    http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/classes/applicationContext.xml</param-value>
</context-param>

<listener>
        <listener-class>
            org.springframework.web.context.ContextLoaderListener
        </listener-class>
</listener>

  <filter>
    <filter-name>struts2</filter-name>
    <filter-class>
        org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter
    </filter-class>  

  </filter>  

  <filter-mapping>
    <filter-name>struts2</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>  

</web-app>

这里引用了struts 和spring的配置文件

struts.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.1.7//EN"
    "http://struts.apache.org/dtds/struts-2.1.7.dtd">
<struts>
    <package name="myPackage" extends="struts-default" >
        <action name="login" class="com.test.action.LoginAction">

            <result name="success">/success.jsp</result>
            <result name="error">/errer.jsp</result>
        </action>
    </package>
</struts>

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"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

    <!--配置数据源属性文件  -->
    <bean id="propertyConfigurer"
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="location">
            <value>/WEB-INF/configs/sqlServer.properties</value>
        </property>
    </bean>

    <!--配置数据源  -->
    <bean id="dataSource"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName">
            <value>${jdbc.driver}</value>
        </property>
        <property name="url">
            <value>${jdbc.url}</value>
        </property>
        <property name="username">
            <value>${jdbc.user}</value>
        </property>
        <property name="password">
            <value>${jdbc.pwd}</value>
        </property>
    </bean>
    <!-- 配置sessoin工厂 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="configLocation" value="classpath:mybatis.xml" />
<!--     <mappers>
        <mapper resource="com/test/sqlMapper/loginMapper.xml"/>
        </mappers> 这里动态的加载  xml文件，就不用手动在 :mybatis.xml 里面写了这里加载的时候是作为session工厂一起进行加载-->
        <property name="mapperLocations" value="classpath:com/test/sqlMapper/*Mapper.xml" />
        <property name="dataSource" ref="dataSource" />
    </bean> 

    <bean id="loginDao" class="org.mybatis.spring.mapper.MapperFactoryBean">
           <!--  用上面直接指定接口位置-->
         <property name="mapperInterface" value="com.test.dao.ILoginDao"/>
        <property name="sqlSessionFactory" ref="sqlSessionFactory" />
    </bean> 

<!--     <bean id="loginAction" class="com.test.action.LoginAction">
        <property name="loginDao" ref="loginDao"></property>
    </bean> -->
</beans>

sql的配置文件

WEB-INF/configs/sqlServer.properties

jdbc.url=jdbc:mysql://localhost:3306/login
jdbc.driver=com.mysql.jdbc.Driver
jdbc.user=root
jdbc.pwd=1234

mybatis.xml

<?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>
    <typeAliases>
        <typeAlias alias="userinfo" type="com.test.entity.UserInfo"/>
    </typeAliases>
<!--     <mappers>
        <mapper resource="com/test/sqlMapper/loginMapper.xml"/>
    </mappers> -->
</configuration>

mybatis.xml 包含的文件

Ssm\src\com\test\sqlMapper\UserInfoMapper.xml

使用接口com.test.dao.ILoginDao来管理 Dao里面的方法

<?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">
<!-- 这个namespace可以理解是调用sql方法的一个执行类 -->
<mapper namespace="com.test.dao.ILoginDao">
    <!-- 这里是完成映射。type里面是映射的实体 column里面是这个实体里面和property表字段想对应的属性 -->
    <resultMap type="com.test.entity.UserInfo" id="userMap">
        <id property="id" column="id"  jdbcType="DECIMAL"/>
        <result property="username" column="username" jdbcType="VARCHAR" />
        <result property="password" column="password" jdbcType="VARCHAR" />
    </resultMap>

    <select id="getUser" parameterType="String" resultMap="userMap">
        select * from userinfo where username=#{userName}
    </select>

    <select id="getUserName" parameterType="int" resultMap="userMap">
        select * from userinfo where id=#{id}
    </select>

</mapper>

mybatis映射文件对应的实体类（类和数据库名一致最好）

package com.test.entity;

public class UserInfo {

    private int id;
    private String username;
    private String password;
    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;
    }

}

通过配置到bean里面的接口去实现sql方法。

因为spring 里面的bean就是给类的进行实例化的。然后通过id进行调用。

mybatis就是通过id进行调用所属的sql的。

那就直接通过spring去实例化一个类（因为不用写类的具体实现，所以就用接口就行），然后去管理mybatis里面的得到id的方法。

Ssm\src\com\test\dao\ILoginDao.java

package com.test.dao;

import java.util.List;

public interface ILoginDao {
    public List getUser(String userName);
    public List getUserName(int userID);
}

最后是一个action的内容

Ssm\src\com\test\action\LoginAction.java

package com.test.action;

import java.util.List;

import com.test.dao.ILoginDao;

public class LoginAction {

        private ILoginDao loginDao;
        private String username;
        private String password;

        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;
        }

        public ILoginDao getLoginDao() {
            return loginDao;
        }
        public void setLoginDao(ILoginDao loginDao) {
            this.loginDao = loginDao;
        }

        public String execute(){
            String userName = getUsername();
            String password = getPassword();
            System.out.println("userName:"+userName+"\n"+"password:"+password);
            List list = loginDao.getUser(userName);
            List list2 = loginDao.getUserName(1);
            if(list.size()>0){
                return "success";
            }else{
                return "error";
            }

        }

}

访问路径：http://localhost:8080/Ssm/login.jsp

源码：http://pan.baidu.com/s/1i43PH3Z