SSM搭建

缓存相关：

• 一级缓存：sqlSession级别的（默认开启）
• 二级缓存：nameSpace级别的（默认关闭）
  

${}和#{}的区别：

${}:预编译的形式，会保留sql中的？，可以防止sql注入。
#{}：取出旳值直接放在sql语句中，会有安全的问题。
大多数情况下使用#{},但是因为原生的jdbc不支持占位符的地方我们就可以使用${}，比如按年份分表的情况：
select * from ${year}_salary where xxx;

目录结构：

1.添加maven依赖（4.3.12.RELEASE）：
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>18.0</version>
</dependency>
<!-- spring****************************************start -->
<!-- Spring ioc模块 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.3.12.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>4.3.12.RELEASE</version>
</dependency>
<!-- Spring 数据库模块 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>4.3.12.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>4.3.12.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>4.3.12.RELEASE</version>
</dependency>
<!-- Spring web模块 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>4.3.12.RELEASE</version>
</dependency>
<!-- Spring AOP模块 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>4.3.12.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
<version>4.3.12.RELEASE</version>
</dependency>
<!-- Spring 基础依赖模块 -->
<dependency>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
<version>1.1.3</version>
</dependency>
<!-- spring*******************************************end -->
<!-- mybatis -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.4</version>
</dependency>
<!-- mybatis-spring整合包 -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.3.0</version>
</dependency>
<!-- 数据库连接包 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.36</version>
</dependency>
<!--google-->
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>21.0</version>
</dependency>
<!--druid-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.0.17</version>
</dependency>
<!--lombok-->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.6</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.40</version>
</dependency>

代码：
Controller:

/** * Created by wb-tianlihui on 2017/11/7. */@Controller@RequestMapping("/")public class TestController {    @Autowired    private BookService service;    @RequestMapping("/test")    @ResponseBody    public String test(@RequestParam(value = "bookId") long id){        Book book = service.getBookById(id);        return JSON.toJSONString(book);    }}

Service:

/** * Created by wb-tianlihui on 2017/11/7. */public interface BookService {    public Book getBookById(Long id);}/** * Created by wb-tianlihui on 2017/11/7. */@Servicepublic class BookServiceImpl implements BookService {    @Autowired    private BookDao dao;    @Override    public Book getBookById(Long id) {        return dao.queryById(id);    }}

Dao：

/** * Created by wb-tianlihui on 2017/11/7. */@Repositorypublic interface BookDao {    /**     * 通过ID查询单本图书     *     * @param id     * @return     */    Book queryById(long id);}

Entity:

/** * Created by wb-tianlihui on 2017/11/7. */@Datapublic class Book {    // 图书ID    private long bookId;    // 图书名称    private String name;    // 馆藏数量    private int number;}

配置：
web.xml:

<web-app metadata-complete="true" version="3.1" 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">  <!-- 如果是用mvn命令生成的xml，需要修改servlet版本为3.1 -->  <!-- 配置DispatcherServlet -->  <servlet>    <servlet-name>spring</servlet-name>    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>    <!-- 配置springMVC需要加载的配置文件        spring-dao.xml,1spring-service.xml,spring-servlet.xml        Mybatis - > spring -> springmvc     -->  </servlet>  <servlet-mapping>    <servlet-name>spring</servlet-name>    <!-- 默认匹配所有的请求 -->    <url-pattern>/</url-pattern>  </servlet-mapping>  <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>

spring-servlet.xml:

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"       xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"       xmlns:context="http://www.springframework.org/schema/context"       xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc.xsd">    <!-- 配置SpringMVC -->    <!-- 1.开启SpringMVC注解模式 -->    <!-- 简化配置：        (1)自动注册DefaultAnootationHandlerMapping,AnotationMethodHandlerAdapter        (2)提供一些列：数据绑定，数字和日期的format @NumberFormat, @DateTimeFormat, xml,json默认读写支持    -->    <mvc:annotation-driven/>    <!-- 2.静态资源默认servlet配置        (1)加入对静态资源的处理：js,gif,png        (2)允许使用"/"做整体映射     -->    <mvc:default-servlet-handler/>    <!-- 3.配置jsp 显示ViewResolver -->    <mvc:view-resolvers>        <mvc:jsp prefix="/WEB-INF/jsp/" suffix=".jsp"/>    </mvc:view-resolvers>    <!-- 4.扫描web相关的bean -->    <context:component-scan base-package="com.tianlh.web"/>    <context:component-scan base-package="com.tianlh.service"/>    <!-- 5.配置数据库相关参数properties的属性：${url} -->    <context:property-placeholder location="classpath:jdbc.properties"/>    <import resource="classpath*:spring/spring-dao.xml"/></beans>

spring-dao.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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd">    <bean name="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}"/>        <!-- 初始化连接大小 -->        <property name="initialSize" value="0"/>        <!-- 连接池最大使用连接数量 -->        <property name="maxActive" value="20"/>        <!-- 连接池最大空闲 -->        <property name="maxIdle" value="20"/>        <!-- 连接池最小空闲 -->        <property name="minIdle" value="0"/>        <!-- 获取连接最大等待时间 -->        <property name="maxWait" value="60000"/>        <property name="validationQuery" value="${validationQuery}"/>        <property name="testOnBorrow" value="false"/>        <property name="testOnReturn" value="false"/>        <property name="testWhileIdle" value="true"/>        <!-- 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒 -->        <property name="timeBetweenEvictionRunsMillis" value="60000"/>        <!-- 配置一个连接在池中最小生存的时间，单位是毫秒 -->        <property name="minEvictableIdleTimeMillis" value="25200000"/>        <!-- 打开removeAbandoned功能 -->        <property name="removeAbandoned" value="true"/>        <!-- 1800秒，也就是30分钟 -->        <property name="removeAbandonedTimeout" value="1800"/>        <!-- 关闭abanded连接时输出错误日志 -->        <property name="logAbandoned" value="true"/>        <!-- 监控数据库 sql注入-->        <property name="filters" value="wall" />        <!--<property name="filters" value="mergeStat"/>-->    </bean>    <!-- 3.配置SqlSessionFactory对象 -->    <bean class="org.mybatis.spring.SqlSessionFactoryBean" id="sqlSessionFactory">        <!-- 注入数据库连接池 -->        <property name="dataSource" ref="dataSource"></property>        <!-- 配置MyBaties全局配置文件:mybatis-config.xml -->       <!-- <property name="configLocation" value="classpath:mybatis-config.xml"></property>-->        <!-- 扫描entity包 使用别名 -->        <property name="typeAliasesPackage" value="com.tianlh.entity"></property>        <!-- 扫描sql配置文件:mapper需要的xml文件 -->        <property name="mapperLocations" value="classpath:mapper/*.xml"></property>    </bean>    <!-- 4.配置扫描Dao接口包，动态实现Dao接口，注入到spring容器中 -->    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">        <!-- 注入sqlSessionFactory -->        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>        <!-- 给出需要扫描Dao接口包 -->        <property name="basePackage" value="com.tianlh.dao"></property>    </bean></beans>

BookDao.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.tianlh.dao.BookDao">    <!-- 接口式编程时：        1.namespace需要指定成接口的全类名        2.接口方名称需要和mapper的id一致    -->    <resultMap id="BaseResultMap" type="com.tianlh.entity.Book">        <id column="book_id" property="bookId" jdbcType="INTEGER"/>        <result column="name" property="name" jdbcType="VARCHAR"/>        <result column="number" property="number" jdbcType="INTEGER"/>    </resultMap>    <!-- 目的：为dao接口方法提供sql语句配置 -->    <select id="queryById" parameterType="long" resultMap="BaseResultMap">        <!-- 具体的sql -->        SELECT        book_id,        name,        number        FROM        book        WHERE        book_id = #{bookId}    </select></mapper>

jdbc.properties:

jdbc.driver=com.mysql.jdbc.Driverjdbc.url=jdbc:mysql://localhost:3306/mysql?useUnicode=true&characterEncoding=utf8jdbc.username=rootjdbc.password=rootvalidationQuery=SELECT 1

Sql:

CREATE TABLE `book` (  `book_id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '图书编号',  `name` varchar(100) NOT NULL COMMENT '图书名称',  `number` int(11) NOT NULL COMMENT '数量',  PRIMARY KEY (`book_id`)) ENGINE=InnoDB AUTO_INCREMENT=1000 DEFAULT CHARSET=utf8 COMMENT='图书'INSERT INTO `book` (`book_id`, `name`, `number`)VALUES    (1000, 'Java', 1),    (1001, 'JSP', 1),    (1002, 'Zookper', 1),    (1003, 'Redis', 1)