Spring總結一-環境搭建

本文主要介紹一個 Spring 項目如何從零開始搭建

使用 Maven 管理

Spring 項目大都是用 Maven 進行導包的，一個 Spring 項目的 pom 文件依賴如下：

    <dependencies>
        <!--測試相關-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
        <!--日誌相關-->
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.3</version>
        </dependency>

        <!--Spring相關\-->
        <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轉換相關-->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.8.7</version>
        </dependency>

        <!-- 封裝了常用集合類 -->
        <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>
        <!-- 連接池 -->
        <dependency>
            <groupId>c3p0</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.1.2</version>
        </dependency>

        <!-- 圖片處理 -->
        <dependency>
            <groupId>net.coobird</groupId>
            <artifactId>thumbnailator</artifactId>
            <version>0.4.8</version>
        </dependency>
        <!-- 驗證碼 -->
        <dependency>
            <groupId>com.github.penggle</groupId>
            <artifactId>kaptcha</artifactId>
            <version>2.3.2</version>
        </dependency>
        <!--文件上傳-->
        <dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>1.3.1</version>
        </dependency>
        <!--redis相關-->
        <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>

每個包相應的作用都已寫在註釋裏。

編寫 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 是前端控制器設計模式的實現，提供 Spring Web MVC 的集中訪問點，而且負責職責的分派，而且與 Spring IoC 容器無縫集成，從而可以獲得 Spring 的所有好處。

url-pattern：表示哪些請求交給 Spring Web MVC 處理， “/” 表示響應所有請求。也可以如 “*.html” 表示攔截所有以 html 爲擴展名的請求。

該 DispatcherServlet 默認使用 WebApplicationContext 作爲上下文，默認從 / WEB-INF/[servlet 名字]-servlet.xml 讀取配置文件。這裏我使用自定義配置文件地址，從類路徑 spring 文件夾下讀取所有 spring - 開頭的文件。

編寫 Spring 配置文件

dao 層–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作用爲讀取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>
    <!--配置數據庫c3p0連接池-->
    <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的接口掃描位置，使用basePackage屬性-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <property name="basePackage" value="com.gyf.o2o.dao"/>
    </bean>
</beans>

service 層–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
">

    <!--查找對應Service類所在位置，方便依賴注入-->
    <context:component-scan base-package="com.gyf.o2o.service"/>

    <!--配置事務管理器，屬性指向之前配置的dataSource-->
    <bean id="transactionManager"
          class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>
    <!--開啓事務註解，再service中可以@Transactional-->
    <tx:annotation-driven transaction-manager="transactionManager"/>
</beans>

web 層–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">
    <!--開啓SpringMVC註解模式-->
    <mvc:annotation-driven/>
    <!--處理靜態資源-->
    <mvc:resources location="/resources/" mapping="/resources/**"/>
    <mvc:default-servlet-handler/>
    <!--定義視圖解析器-->
    <bean id="viewResolver"          class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/html/"/>
        <property name="suffix" value=".html"/>
    </bean>
    <!-- 文件上傳-->
    <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>

使用是因爲之前再 web.xml 中配置了所有請求全部被 SpringMVC 攔截，就導致了靜態資源無法訪問，在 springMVC-servlet.xml 中配置 後，會在 Spring MVC 上下文中定義一個 DefaultServletHttpRequestHandler，它會像一個檢查員，對進入 DispatcherServlet 的 URL 進行篩查，如果發現是靜態資源的請求，就將該請求轉由 Web 應用服務器默認的 Servlet 處理，如果不是靜態資源的請求，才由 DispatcherServlet 繼續處理。

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>
    <!--  配置全局屬性-->
    <settings>
        <!--獲取自增主鍵值-->
        <setting name="useGeneratedKeys" value="true"/>
        <!--使用列標籤替換列別名-->
        <setting name="useColumnLabel" value="true"/>
        <!--開啓駝峯命名轉換-->
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
</configuration>