前言:最近再寫一款視頻播放器的後臺,踩了不少坑,在此總結。html
前提:搭建配置無缺的Spring-MyBatis項目前端
1.流程分析,數據庫設計(看似無用,真正作起來真的須要這個東西幫忙整理下思路)java
2.dao層,mapper層,pojo層(能夠自動生成),service層,impl層的編寫mysql
3.controll層的編寫git
流程圖:github
項目結構:web
controller 控制層,和前端相聯繫,主要負責從頁面獲取數據,傳遞數據到頁面。spring
dao 數據層,和數據庫聯繫,對數據庫進行增刪改查接口的書寫。sql
mapping dao層的配置文件,這一層在mybatis裏面很重要,是對應dao層的數據庫實現層,數據庫邏輯都是寫在裏面,也能夠寫優化的數據庫代碼。數據庫
pojo 對應數據庫的對象,也是dao層直接操做的對象,能夠在這裏面添加返回Json的toString()方法。這樣返回的對象就能夠直接爲Json了。
service 中間層,也是服務層,用來寫dao層的接口,處理邏輯。
service.impl 服務實現層,實現接口邏輯的,裏面放的是實體類,判斷是否爲空等操做能夠在這裏面進行。
utils 通用公共層
jdbc.properties 數據庫配置文件,裏面配置着數據庫參數
log4j.properties 日誌配置文件,能夠在控制檯或者文件裏面輸出日誌文件,以便收取信息修正bug。
mybatis-properties mybatis配置文件,配置相關的內容。
spring-dao spring和mybatis的整合文件,這個文件將兩個的配置完美結合了,也是關鍵。
spring-mvc 這個就是servlet的配置文件了,前端能不能正常跑起來這個很重要。
WEB-INF 這裏面的文件前端沒法訪問的,因此直接在地址上面輸入這裏面的文件怎麼都是404,不配置的話只能後臺調用
web.xml 關鍵文件,須要在裏面配置DispatcherServerlet,配置過濾器以及監聽。
pom.xml 這個不是這個目錄裏面的是外層目錄,主要是maven的配置文件,拿着這個就不用苦逼的烤jar包了。
先建立maven項目,配置pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>MyBatisSpringMVC</groupId> <artifactId>MyBatisSpringMVC</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>war</packaging> <url>http://maven.apache.org</url> <properties> <!-- spring版本號 --> <spring.version>4.0.2.RELEASE</spring.version> <!-- mybatis版本號 --> <mybatis.version>3.2.6</mybatis.version> <!-- log4j日誌文件管理包版本 --> <slf4j.version>1.7.7</slf4j.version> <log4j.version>1.2.17</log4j.version> </properties> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> <!-- 表示開發的時候引入,發佈的時候不會加載此包 --> <scope>test</scope> </dependency> <!-- spring核心包 --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</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-oxm</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-jdbc</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-aop</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>${spring.version}</version> </dependency> <!-- mybatis核心包 --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>${mybatis.version}</version> </dependency> <!-- mybatis/spring包 --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.2.2</version> </dependency> <!-- 導入java ee jar 包 --> <dependency> <groupId>javax</groupId> <artifactId>javaee-api</artifactId> <version>7.0</version> </dependency> <!-- 導入Mysql數據庫連接jar包 --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.30</version> </dependency> <!-- 導入dbcp的jar包,用來在applicationContext.xml中配置數據庫 --> <dependency> <groupId>commons-dbcp</groupId> <artifactId>commons-dbcp</artifactId> <version>1.2.2</version> </dependency> <!-- JSTL標籤類 --> <dependency> <groupId>jstl</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency> <!-- 日誌文件管理包 --> <!-- log start --> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>${log4j.version}</version> </dependency> <!-- 格式化對象,方便輸出日誌 --> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.1.41</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>${slf4j.version}</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>${slf4j.version}</version> </dependency> <!-- log end --> <!-- 映入JSON --> <dependency> <groupId>org.codehaus.jackson</groupId> <artifactId>jackson-mapper-asl</artifactId> <version>1.9.13</version> </dependency> <!-- 上傳組件包 --> <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3.1</version> </dependency> <dependency> <groupId>commons-io</groupId> <artifactId>commons-io</artifactId> <version>2.4</version> </dependency> <dependency> <groupId>commons-codec</groupId> <artifactId>commons-codec</artifactId> <version>1.9</version> </dependency> </dependencies> <build> <sourceDirectory>src</sourceDirectory> <plugins> <plugin> <artifactId>maven-compiler-plugin</artifactId> <version>3.7.0</version> <configuration> <source>1.8</source> <target>1.8</target> </configuration> </plugin> <plugin> <artifactId>maven-war-plugin</artifactId> <version>3.0.0</version> <configuration> <warSourceDirectory>WebContent</warSourceDirectory> </configuration> </plugin> </plugins> </build> </project>
再配置jdbc.properties
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/vddb
username=root
password=1234
initialSize=0
maxActive=20
maxIdle=20
minIdle=1
maxWait=60000
配置mybatis-config.xml配置文件
<?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> <!-- 使用jdbc的getGeneratedKeys獲取數據庫自增值 --> <setting name="useGeneratedKeys" value="true" /> <!-- 使用列別名替換別名 --> <setting name="useColumnLabel" value="true" /> <!-- 開啓駝峯命名規範 --> <setting name="mapUnderscoreToCamelCase" value="true" /> </settings> </configuration>
配置spring-dao.xml配置文件
<?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:p="http://www.springframework.org/schema/p" 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-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 約定大於配置 --> <!-- 自動掃描 --> <context:component-scan base-package="com.mybatis.spring.*" /> <!-- 1.數據庫鏈接池 --> <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="location" value="classpath:jdbc.properties" /> </bean> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${driver}" /> <property name="url" value="${url}" /> <property name="username" value="${username}" /> <property name="password" value="${password}" /> <!-- 初始化鏈接大小 --> <property name="initialSize" value="${initialSize}"></property> <!-- 鏈接池最大數量 --> <property name="maxActive" value="${maxActive}"></property> <!-- 鏈接池最大空閒 --> <property name="maxIdle" value="${maxIdle}"></property> <!-- 鏈接池最小空閒 --> <property name="minIdle" value="${minIdle}"></property> <!-- 獲取鏈接最大等待時間 --> <property name="maxWait" value="${maxWait}"></property> </bean> <!-- 2.配置sqlsession對象,不須要mybatis的配置映射文件 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 注入數據庫鏈接池 --> <property name="dataSource" ref="dataSource" /> <!-- 配置MyBatis全局配置文件:mybatis-config.xml --> <property name="configLocation" value="classpath:mybatis-config.xml" /> <!-- 掃描sql配置文件:mapper須要的xml文件 --> <property name="mapperLocations" value="classpath:com/mybatis/spring/mapping/*.xml" /> <!-- 自動掃描數據庫實體pojo文件 --> <property name="typeAliasesPackage" value="com.mybatis.spring.pojo" /> </bean> <!-- 4:DAO接口所在包名,Spring會自動查找其下的類 ,動態實現Dao接口注入到Spring容器中 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!-- 給出須要掃描的Dao接口包 --> <property name="basePackage" value="com.mybatis.spring.dao" /> <!-- 注入sqlSessionFactory --> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> <!-- (事務管理)transaction manager, use JtaTransactionManager for global tx --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource" /> </bean> </beans>
配置spring-mvc.xml配置文件
<?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:p="http://www.springframework.org/schema/p" 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-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 引用註解 --> <mvc:annotation-driven /> <mvc:default-servlet-handler /> <!-- 自動掃描該包,使SpringMVC認爲包下用了@controller註解的類是控制器 --> <context:component-scan base-package="com.mybatis.spring.controller.*" /> <!-- 靜態文件訪問路徑權限,意思就是下面的location目錄會跳過攔截直接訪問 --> <mvc:resources location="/WEB-INF/pages/" mapping="/pages/*" /> <!--避免IE執行AJAX時,返回JSON出現下載文件 --> <bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"> <property name="supportedMediaTypes"> <list> <value>text/html;charset=UTF-8</value> </list> </property> </bean> <!-- 啓動SpringMVC的註解功能,完成請求和註解POJO的映射 --> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> <property name="messageConverters"> <list> <ref bean="mappingJacksonHttpMessageConverter" /> <!-- JSON轉換器 --> </list> </property> </bean> <!-- 定義跳轉的文件的先後綴 ,視圖模式配置 --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <!-- 這裏的配置個人理解是自動給後面action的方法return的字符串加上前綴和後綴,變成一個 可用的url地址 --> <property name="prefix" value="/WEB-INF/pages/" /> <property name="suffix" value=".jsp" /> </bean> <!-- 配置文件上傳,若是沒有使用文件上傳能夠不用配置,固然若是不配,那麼配置文件中也沒必要引入上傳組件包 --> <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!-- 默認編碼 --> <property name="defaultEncoding" value="utf-8" /> <!-- 文件大小最大值 --> <property name="maxUploadSize" value="10485760000" /> <!-- 內存中的最大值 --> <property name="maxInMemorySize" value="40960" /> </bean> </beans>
配置log4j.properties日誌輸出文件
#定義LOG輸出級別
log4j.rootLogger=INFO,Console,File
#定義日誌輸出目的地爲控制檯
log4j.appender.Console=org.apache.log4j.ConsoleAppender
log4j.appender.Console.Target=System.out
#能夠靈活地指定日誌輸出格式,下面一行是指定具體的格式
log4j.appender.Console.layout = org.apache.log4j.PatternLayout
log4j.appender.Console.layout.ConversionPattern=%d[%t]%-5p[%c] - %m%n
#文件大小到達指定尺寸的時候產生一個新的文件
log4j.appender.File = org.apache.log4j.RollingFileAppender
#指定輸出目錄
log4j.appender.File.File = E:Users/SpringMVC/MyBatisSpringMVC/logs/ssm.log
#定義文件最大大小
log4j.appender.File.MaxFileSize = 10MB
# 輸出因此日誌,若是換成DEBUG表示輸出DEBUG以上級別日誌
log4j.appender.File.Threshold = ALL
log4j.appender.File.layout = org.apache.log4j.PatternLayout
log4j.appender.File.layout.ConversionPattern =[%p] [%d{yyyy-MM-dd HH\:mm\:ss}][%c]%m%n
而後再是配置web.xml文件
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5"> <display-name>MyBatis_Spring_MVC</display-name> <welcome-file-list> <welcome-file>register.jsp</welcome-file> </welcome-file-list> <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> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath*:config/applicationContext.xml</param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <listener> <listener-class> org.springframework.web.context.ContextCleanupListener</listener-class> </listener> <servlet> <servlet-name>spring-mvc</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-*.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>spring-mvc</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app>
直接複製粘貼過來,運氣好的話能夠直接跑,可是若是運氣很差,改都很差下手,所以,配置仍是須要熟悉,下面是當時碰見的幾個比較嚴重的bug,也是對這個框架不甚其解,總之,配置上面的事情須要瞭解,可是也不能花太多的時間,畢竟是造輪子的事情,更多的應該體如今代碼上面。
這個也是不少網上出現的問題,確實很難解決,個人狀況出如今跳轉的時候。
解決辦法:這個是servlet裏面的配置有問題,在servlet裏面,添加了<mvc:default-servlet-handler />問題就解決了。
這個問題是在自定義servlet的時候出現,web.xml會默認掃描這個文件,可是默認的路徑是和他一個路徑。
解決辦法:在servlet裏面添加下面代碼便可
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-*.xml</param-value>
</init-param>
在此以前,你須要知道你要實現的功能,須要對哪些數據進行操做,因此在編碼前,你須要設計好數據庫,整套流程有個明確的認識,這樣寫起來也比較有層次性。
在這裏我用到寫流程的軟件是 Processon(https://www.processon.com)
數據庫作完了就能夠往代碼裏面添加最簡單的增刪改查功能了,這裏有一個自動生成數據庫操做對象以及mapper文件的方法,大大提升了工做效率。
須要的是一個xml文件,兩個jar包,隨便放在哪一個文件夾,寫在項目裏面是用到的時候省得處處找。
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"> <generatorConfiguration> <!-- 數據庫驅動 --> <classPathEntry location="mysql-connector-java-5.1.25-bin.jar" /> <context id="DB2Tables" targetRuntime="MyBatis3"> <commentGenerator> <property name="suppressDate" value="true" /> <!-- 是否去除自動生成的註釋 true:是 : false:否 --> <property name="suppressAllComments" value="true" /> </commentGenerator> <!--數據庫連接URL,用戶名、密碼 --> <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://localhost:3306/vddb" userId="root" password="1234"> </jdbcConnection> <javaTypeResolver> <property name="forceBigDecimals" value="false" /> </javaTypeResolver> <!-- 生成模型的包名和位置 --> <javaModelGenerator targetPackage="com.mybatis.spring.pojo" targetProject="src"> <property name="enableSubPackages" value="true" /> <property name="trimStrings" value="true" /> </javaModelGenerator> <!-- 生成映射文件的包名和位置 --> <sqlMapGenerator targetPackage="com.mybatis.spring.mapping" targetProject="src"> <property name="enableSubPackages" value="true" /> </sqlMapGenerator> <!-- 生成DAO的包名和位置 --> <javaClientGenerator type="XMLMAPPER" targetPackage="com.mybatis.spring.dao" targetProject="src"> <property name="enableSubPackages" value="true" /> </javaClientGenerator> <!-- 要生成的表 tableName是數據庫中的表名或視圖名 domainObjectName是實體類名 --> <table tableName="registerinfo" domainObjectName="RegisterInfo" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"></table> </context> </generatorConfiguration>
裏面須要配置的是數據庫的名稱以及帳號密碼,還有就是對應的表和輸出的對象名
腳本爲:java -jar mybatis-generator-core-1.3.2.jar -configfile generatorConfig.xml -overwrite
執行成功會有成功的提示,接下來就是去文件夾裏面找文件就行了。
具體參見 http://www.cnblogs.com/xuhai/p/8011957.html
package com.mybatis.spring.dao; import com.mybatis.spring.pojo.Resources; public interface ResourcesMapper { int deleteByPrimaryKey(String index); int insert(Resources record); int insertSelective(Resources record); Resources selectByPrimaryKey(String index); int updateByPrimaryKeySelective(Resources record); int updateByPrimaryKey(Resources record); }
<?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.mybatis.spring.dao.ResourcesMapper" > <resultMap id="BaseResultMap" type="com.mybatis.spring.pojo.Resources" > <id column="index" property="index" jdbcType="VARCHAR" /> <result column="image" property="image" jdbcType="VARCHAR" /> <result column="title" property="title" jdbcType="VARCHAR" /> <result column="video" property="video" jdbcType="VARCHAR" /> <result column="page_num" property="pageNum" jdbcType="VARCHAR" /> </resultMap> <sql id="Base_Column_List" > index, image, title, video, page_num </sql> <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.String" > select <include refid="Base_Column_List" /> from resources where index = #{index,jdbcType=VARCHAR} </select> <delete id="deleteByPrimaryKey" parameterType="java.lang.String" > delete from resources where index = #{index,jdbcType=VARCHAR} </delete> <insert id="insert" parameterType="com.mybatis.spring.pojo.Resources" > insert into resources (index, image, title, video, page_num) values (#{index,jdbcType=VARCHAR}, #{image,jdbcType=VARCHAR}, #{title,jdbcType=VARCHAR}, #{video,jdbcType=VARCHAR}, #{pageNum,jdbcType=VARCHAR}) </insert> <insert id="insertSelective" parameterType="com.mybatis.spring.pojo.Resources" > insert into resources <trim prefix="(" suffix=")" suffixOverrides="," > <if test="index != null" > index, </if> <if test="image != null" > image, </if> <if test="title != null" > title, </if> <if test="video != null" > video, </if> <if test="pageNum != null" > page_num, </if> </trim> <trim prefix="values (" suffix=")" suffixOverrides="," > <if test="index != null" > #{index,jdbcType=VARCHAR}, </if> <if test="image != null" > #{image,jdbcType=VARCHAR}, </if> <if test="title != null" > #{title,jdbcType=VARCHAR}, </if> <if test="video != null" > #{video,jdbcType=VARCHAR}, </if> <if test="pageNum != null" > #{pageNum,jdbcType=VARCHAR}, </if> </trim> </insert> <update id="updateByPrimaryKeySelective" parameterType="com.mybatis.spring.pojo.Resources" > update resources <set > <if test="image != null" > image = #{image,jdbcType=VARCHAR}, </if> <if test="title != null" > title = #{title,jdbcType=VARCHAR}, </if> <if test="video != null" > video = #{video,jdbcType=VARCHAR}, </if> <if test="pageNum != null" > page_num = #{pageNum,jdbcType=VARCHAR}, </if> </set> where index = #{index,jdbcType=VARCHAR} </update> <update id="updateByPrimaryKey" parameterType="com.mybatis.spring.pojo.Resources" > update resources set image = #{image,jdbcType=VARCHAR}, title = #{title,jdbcType=VARCHAR}, video = #{video,jdbcType=VARCHAR}, page_num = #{pageNum,jdbcType=VARCHAR} where index = #{index,jdbcType=VARCHAR} </update> </mapper>
package com.mybatis.spring.pojo; public class Resources { private String index; private String image; private String title; private String video; private String pageNum; public String getIndex() { return index; } public void setIndex(String index) { this.index = index == null ? null : index.trim(); } public String getImage() { return image; } public void setImage(String image) { this.image = image == null ? null : image.trim(); } public String getTitle() { return title; } public void setTitle(String title) { this.title = title == null ? null : title.trim(); } public String getVideo() { return video; } public void setVideo(String video) { this.video = video == null ? null : video.trim(); } public String getPageNum() { return pageNum; } public void setPageNum(String pageNum) { this.pageNum = pageNum == null ? null : pageNum.trim(); } @Override public String toString() { return "{\"index\":\"" + index + "\",\"image\":\"" + image + "\",\"title\":\"" + title + "\",\"video\":\"" + video + "\",\"pageNum\":\"" + pageNum + "\"}"; } }
上面的代碼分別爲dao層,mapping層,pojo層。
這個時候須要對dao層進行service代碼的編寫,用於書寫代碼邏輯。
package com.mybatis.spring.service; import com.mybatis.spring.pojo.Resources; public interface IResourcesService { public int deleteByPrimaryKey(String index); public int insert(Resources record); public int insertSelective(Resources record); public Resources selectByPrimaryKey(String index); public int updateByPrimaryKeySelective(Resources record); public int updateByPrimaryKey(Resources record); }
package com.mybatis.spring.service.impl; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import com.mybatis.spring.dao.ResourcesMapper; import com.mybatis.spring.pojo.Resources; import com.mybatis.spring.service.IResourcesService; @Service public class ResourcesServiceImpl implements IResourcesService { @Autowired private ResourcesMapper resourcesMapper; @Override public int deleteByPrimaryKey(String index) { return resourcesMapper.deleteByPrimaryKey(index); } @Override public int insert(Resources record) { return resourcesMapper.insert(record); } @Override public int insertSelective(Resources record) { return resourcesMapper.insertSelective(record); } @Override public Resources selectByPrimaryKey(String index) { return resourcesMapper.selectByPrimaryKey(index); } @Override public int updateByPrimaryKeySelective(Resources record) { return resourcesMapper.updateByPrimaryKeySelective(record); } @Override public int updateByPrimaryKey(Resources record) { return resourcesMapper.updateByPrimaryKey(record); } }
這裏面註解的用法:我對註解不是很明白因此得解釋一下,實現類須要添加Autowired是要自動添加dao層的pojo對象,所以能夠直接返回相應值(有錯誤請及時糾正),Service是後面Controller層使用的時候告訴那邊
這個加載的是dao層的服務,用來關聯先後關係。
package com.mybatis.spring.controller; import java.util.ArrayList; import java.util.List; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.context.annotation.ComponentScan; import org.springframework.context.annotation.Configuration; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RequestParam; import com.mybatis.spring.pojo.LoginResult; import com.mybatis.spring.pojo.Register; import com.mybatis.spring.pojo.Resources; import com.mybatis.spring.service.IResourcesService; @Controller @Configuration @ComponentScan("com.mybatis.spring.controller") // No need to include component-scan in xml public class ResourcesController { @Autowired private IResourcesService iResourcesService; @RequestMapping(value = "/login.do", method = RequestMethod.POST) public String login(@RequestParam("unicode") String unicode, Model model) throws Exception { // 判斷unicode是否存在,不存在的resources爲null。 Resources login_resources = iResourcesService.selectByPrimaryKey(unicode); Register register = new Register(); LoginResult loginResult = new LoginResult(); Resources resources = new Resources(); List<Resources> resourcesList = new ArrayList<Resources>(); if (null == login_resources.toString()) { // 說明沒有註冊登陸,Flag設置爲false register.setFlag("false"); loginResult.setFlag("false"); // 添加試看視頻,返回爲前三個 for (int i = 1; i <= 3; i++) { resources = iResourcesService.selectByPrimaryKey(String.valueOf(i)); resourcesList.add(resources); } loginResult.setResourcesList(resourcesList); model.addAttribute("result", loginResult); return "result"; } else { // 登陸成功,返回登陸成功的數值 register.setFlag("true"); loginResult.setFlag("true"); // 返回全部視頻的值 for (int i = 1; i <= 12; i++) { resources = iResourcesService.selectByPrimaryKey(String.valueOf(i)); resourcesList.add(resources); } loginResult.setResourcesList(resourcesList); model.addAttribute("result", loginResult); return "result"; } } }
這段代碼編寫得比較失敗得,由於controller裏面最好不須要這麼多判斷邏輯,這些都應該丟給service層來處理就好,好在代碼邏輯並不複雜,因此就這樣將就了。
須要說明的地方:
@Controller 讓配置的掃描在此有效,而且告知servlet這個是控制層。
@Configuration
@ComponentScan("com.mybatis.spring.controller") 這兩個要一塊兒用,用來掃描包的,和spring-mvc.xml裏面配置的做用是同樣的
@RequestMapping(value = "/login.do", method = RequestMethod.POST,produces = { "application/json;charset=UTF-8") 映射的路徑,能夠和前端的jsp文件裏面的action相對應。後面的produces是確認返回代碼格式。
@RequestParam("unicode") String unicode 這個是能夠從前端獲取的文件,直接從前端獲取,不須要特地獲取,能夠直接使用。
return "result"; 這裏面的return可不是返回一個字符串,他是本身去尋找result.jsp這個文件去了,model能夠把獲取的值傳遞到前端。
@ResponseBody 返回值,能夠在方法體裏面定義返回的格式,好比不想返回頁面,而是Json數值,那麼就須要這個註解
<%@ page import="java.sql.*" language="java"
contentType="text/html; charset=utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>登陸界面</title>
</head>
<body>
<center>
<form action="login" name="loginForm" method="post">
<table>
<tr>
<td>帳號:</td>
<td><input type="text" name="username"></td>
</tr>
<tr>
<td>密碼:</td>
<td><input type="password" name="password"></td>
</tr>
<tr>
<td colspan="1"><input type="submit" value="登陸"></td>
<td colspan="1"><a href="register.jsp">註冊</a></td>
</tr>
</table>
</form>
</center>
</body>
</html>
注:上面的代碼不是徹底對應