用ssm写一个简易后台

SSM是Spring+SpringMVC+MyBatis的缩写，它是一种Java企业级应用开发框架。下面是一个简单的SSM后台的实现步骤：

1. 配置数据库

在`src/main/resources`目录下创建`jdbc.properties`文件，配置数据库连接信息，例如：

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/test
jdbc.username=root
jdbc.password=123456

2. 配置Spring框架

在`src/main/resources`目录下创建`applicationContext.xml`文件，配置Spring框架的相关信息，例如：

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

    <!-- 自动扫描包 -->
    <context:component-scan base-package="com.example.controller"/>

    <!-- 配置视图解析器 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

    <!-- 配置MyBatis -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.example.mapper"/>
    </bean>
    <bean class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:mapper/**/*.xml"/>
    </bean>

    <!-- 配置dataSource -->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource"
          init-method="init" destroy-method="close">
        <property name="driverClassName" value="${jdbc.driver}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
        <property name="maxActive" value="20"/>
        <property name="initialSize" value="1"/>
        <property name="maxWait" value="60000"/>
        <property name="minIdle" value="1"/>
        <property name="validationQuery" value="SELECT 1 FROM DUAL"/>
        <property name="testOnBorrow" value="false"/>
        <property name="testOnReturn" value="false"/>
        <property name="testWhileIdle" value="true"/>
    </bean>

    <!-- 开启Spring事务管理 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>
    <tx:annotation-driven transaction-manager="transactionManager"/>

</beans>

3. 配置MyBatis框架

在`src/main/resources`目录下创建`mybatis-config.xml`文件，配置MyBatis框架的相关信息，例如：

<?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>
    <!-- 配置别名 -->
    <typeAliases>
        <package name="com.example.entity"/>
    </typeAliases>

    <!-- 配置插件 -->
    <plugins>
        <plugin interceptor="com.example.interceptor.PageInterceptor"/>
    </plugins>

    <!-- 配置分页插件 -->
    <objectFactory type="com.example.factory.PageFactory"/>

    <!-- 配置mapper -->
    <mappers>
        <mapper resource="mapper/ExampleMapper.xml"/>
    </mappers>
</configuration>

4. 编写Controller

在`src/main/java`目录下创建一个Controller类，例如：

@Controller
@RequestMapping("/example")
public class ExampleController {

    @Autowired
    private ExampleService exampleService;

    @RequestMapping("/list")
    public ModelAndView list() {
        List<Example> exampleList = exampleService.getExampleList();
        ModelAndView mv = new ModelAndView("example/list");
        mv.addObject("exampleList", exampleList);
        return mv;
    }

    @RequestMapping("/add")
    public ModelAndView add(Example example) {
        exampleService.addExample(example);
        ModelAndView mv = new ModelAndView("redirect:/example/list");
        return mv;
    }

    @RequestMapping("/delete")
    public String delete(int id) {
        exampleService.deleteExample(id);
        return "redirect:/example/list";
    }

}

5. 编写Service

在`src/main/java`目录下创建一个Service类，例如：

@Service
public class ExampleService {

    @Autowired
    private ExampleMapper exampleMapper;

    public List<Example> getExampleList() {
        return exampleMapper.getExampleList();
    }

    public void addExample(Example example) {
        exampleMapper.addExample(example);
    }

    public void deleteExample(int id) {
        exampleMapper.deleteExample(id);
    }

}

6. 编写Mapper

在`src/main/resources/mapper`目录下创建一个Mapper接口和对应的XML文件，例如：

public interface ExampleMapper {

    List<Example> getExampleList();

    void addExample(Example example);

    void deleteExample(int id);

}

<mapper namespace="com.example.mapper.ExampleMapper">

    <select id="getExampleList" resultType="com.example.entity.Example">
        SELECT * FROM example
    </select>

    <insert id="addExample" parameterType="com.example.entity.Example">
        INSERT INTO example (name, age) VALUES (#{name}, #{age})
    </insert>

    <delete id="deleteExample">
        DELETE FROM example WHERE id = #{id}
    </delete>

</mapper>

7. 编写JSP页面

在`src/main/webapp/WEB-INF/views/example`目录下创建JSP页面，例如：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
  <head>
    <title>Example List</title>
  </head>
  <body>
    <table>
      <tr>
        <th>ID</th>
        <th>Name</th>
        <th>Age</th>
        <th>Operation</th>
      </tr>
      <c:forEach items="${exampleList}" var="example">
        <tr>
          <td>${example.id}</td>
          <td>${example.name}</td>
          <td>${example.age}</td>
          <td>
            <a href="/example/delete?id=${example.id}">Delete</a>
          </td>
        </tr>
      </c:forEach>
    </table>
    <hr/>
    <form action="/example/add" method="post">
      <label>Name:</label>
      <input type="text" name="name"/><br/>
      <label>Age:</label>
      <input type="text" name="age"/><br/>
      <input type="submit" value="Add"/>
    </form>
  </body>
</html>

以上就是一个简单的SSM后台的实现步骤。