Spring总结一:环境搭建

本文主要介绍一个Spring项目如何从零开始搭建

使用Maven管理

Spring项目大都是用Maven进行导包的，一个Spring项目的pom文件依赖如下：

<dependencies>
    <!--测试相关-->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
    </dependency>
    <!--日志相关-->
    <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-classic</artifactId>
        <version>1.2.3</version>
    </dependency>

    <!--Spring相关\-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-beans</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-web</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>${spring.version}</version>
        <scope>test</scope>
    </dependency>
    <!-- Servlet Web -->
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
    </dependency>

    <!--json转换相关-->
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.8.7</version>
    </dependency>

    <!-- 封装了常用集合类 -->
    <dependency>
        <groupId>commons-collections</groupId>
        <artifactId>commons-collections</artifactId>
        <version>3.2</version>
    </dependency>

    <!-- Mybatis -->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.4.2</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis-spring</artifactId>
        <version>1.3.1</version>
    </dependency>

    <!-- Mysql -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.38</version>
    </dependency>
    <!-- 连接池 -->
    <dependency>
        <groupId>c3p0</groupId>
        <artifactId>c3p0</artifactId>
        <version>0.9.1.2</version>
    </dependency>

    <!-- 图片处理 -->
    <dependency>
        <groupId>net.coobird</groupId>
        <artifactId>thumbnailator</artifactId>
        <version>0.4.8</version>
    </dependency>
    <!-- 验证码 -->
    <dependency>
        <groupId>com.github.penggle</groupId>
        <artifactId>kaptcha</artifactId>
        <version>2.3.2</version>
    </dependency>
    <!--文件上传-->
    <dependency>
        <groupId>commons-fileupload</groupId>
        <artifactId>commons-fileupload</artifactId>
        <version>1.3.1</version>
    </dependency>
    <!--redis相关-->
    <dependency>
        <groupId>redis.clients</groupId>
        <artifactId>jedis</artifactId>
        <version>2.9.0</version>
    </dependency>
</dependencies>

<build>
    <finalName>o2o</finalName>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.6.1</version>
            <configuration>
                <source>1.8</source>
                <target>1.8</target>
                <encoding>UTF8</encoding>
            </configuration>
        </plugin>
    </plugins>
</build>

每个包相应的作用都已写在注释里。

编写Web.xml

<web-app 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"
         version="3.1" metadata-complete="true">
  <display-name>Archetype Created Web Application</display-name>
  <servlet>
      <servlet-name>spring-dispatcher</servlet-name>
      <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
      <init-param>
          <param-name>contextConfigLocation</param-name>
          <param-value>classpath:spring/spring-*.xml</param-value>
      </init-param>
  </servlet>
    
    <servlet-mapping>
        <servlet-name>spring-dispatcher</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

</web-app>

DispatcherServlet 是前端控制器设计模式的实现，提供 Spring Web MVC 的集中访问点，而且负责职责的分派，而且与 Spring IoC 容器无缝集成，从而可以获得 Spring 的所有好处。

url-pattern：表示哪些请求交给 Spring Web MVC 处理， “/” 表示响应所有请求。也可以如 “*.html” 表示拦截所有以 html 为扩展名的请求。

该 DispatcherServlet 默认使用WebApplicationContext作为上下文，默认从/WEB-INF/[servlet 名字]-servlet.xml读取配置文件。这里我使用自定义配置文件地址，从类路径spring文件夹下读取所有spring-开头的文件。

编写Spring配置文件

dao层–spring-dao.xml

<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"
       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">

    <!--此Bean作用为读取properties到全局-->
    <bean class="com.gyf.o2o.util.EncryptPropertyPlaceholderConfigure">
        <property name="locations">
            <list>
                <value>classpath:jdbc.properties</value>
                <value>classpath:redis.properties</value>
            </list>
        </property>
        <property name="fileEncoding" value="UTF-8"/>
    </bean>
    <!--配置数据库c3p0连接池-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${jdbc.driver}"/>
        <property name="jdbcUrl" value="${jdbc.url}"/>
        <property name="user" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
        <property name="maxPoolSize" value="30"/>
        <property name="minPoolSize" value="10"/>
        <property name="autoCommitOnClose" value="false"/>
        <property name="checkoutTimeout" value="10000"/>
        <property name="acquireRetryAttempts" value="2"/>
    </bean>

    <!--配置SessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="typeAliasesPackage" value="classpath:com.gyf.o2o.entity"/>
        <property name="mapperLocations" value="classpath:mapper/*.xml"/>
    </bean>

    <!--配置Mybatis的接口扫描位置，使用basePackage属性-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <property name="basePackage" value="com.gyf.o2o.dao"/>
    </bean>
</beans>

service层–spring-service.xml

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

    <!--查找对应Service类所在位置，方便依赖注入-->
    <context:component-scan base-package="com.gyf.o2o.service"/>

    <!--配置事务管理器，属性指向之前配置的dataSource-->
    <bean id="transactionManager"
          class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>
    <!--开启事务注解，再service中可以@Transactional-->
    <tx:annotation-driven transaction-manager="transactionManager"/>
</beans>

web层–spring-web

<?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/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/mvc
   http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">
    <!--开启SpringMVC注解模式-->
    <mvc:annotation-driven/>
    <!--处理静态资源-->
    <mvc:resources location="/resources/" mapping="/resources/**"/>
    <mvc:default-servlet-handler/>
    <!--定义视图解析器-->
    <bean id="viewResolver"          class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/html/"/>
        <property name="suffix" value=".html"/>
    </bean>
	<!-- 文件上传-->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="utf-8"/>
        <property name="maxUploadSize" value="20971520"/><!-- 20M -->
        <property name="maxInMemorySize" value="20971520"/>
    </bean>
    <context:component-scan base-package="com.gyf.o2o.web"/>
</beans>

使用<mvc:default-servlet-handler />是因为之前再web.xml中配置了所有请求全部被SpringMVC拦截，就导致了静态资源无法访问，在 springMVC-servlet.xml 中配置 <mvc:default-servlet-handler /> 后，会在 Spring MVC 上下文中定义一个DefaultServletHttpRequestHandler，它会像一个检查员，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。

mybatis配置

<?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>
    <!--  配置全局属性-->
    <settings>
        <!--获取自增主键值-->
        <setting name="useGeneratedKeys" value="true"/>
        <!--使用列标签替换列别名-->
        <setting name="useColumnLabel" value="true"/>
        <!--开启驼峰命名转换-->
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
</configuration>