一般在web開發中,會話管理是很重要的一部分,用於存儲與用戶相關的一些數據。對於JAVA開發者來講,項目中的session通常由Tomcat或者jetty容器來管理。css
儘管使用特定的容器能夠很好地實現會話管理,可是獨立容器掛掉或者因爲其餘緣由重啓會致使用戶信息丟失,而且沒法支持分佈式集羣會話管理。html
上圖舉例:html5
這是一個簡單的負載均衡集羣架構模型,後端三臺Tomcat服務,假設每臺服務都使用本身的會話管理,而集羣策略是基於加權輪詢的方式實現。試想一下,用戶是否是永遠沒法登錄系統?java
固然,你可能會想,我可使用基於IP_hash的方式實現負載均衡嘛。可是若是地區分佈相對單一,產生的hash值分佈可能也不會太均勻,那就起不到負載均衡的做用了。web
通常來講,有兩種解決方案,session複製和session統一管理。對於session複製,簡單的幾臺仍是能夠的,可是若是上百臺甚至上千臺就要考慮複製成本問題了。redis
對於統一session管理能夠是關係型數據庫,好比MySql(基本不用,考慮到效率問題);非關係型數據庫 redis,memcache等等。spring
基於Tomcat的會話插件實現tomcat-redis-session-manager 和tomcat-memcache-session-manager,會話統一由NoSql管理。對於項目自己來講,無須改動代碼,只須要簡單的配置Tomcat的server.xml就能夠解決問題。可是插件太依賴於容器,而且對於Tomcat各個版本的支持不是特別的好數據庫
重寫Tomcat的session管理,代碼耦合度高,不利於維護。express
使用開源的session管理框架,好比spring_session,既不須要修改Tomcat配置,又無須重寫代碼,只須要配置相應的參數便可。json
下面,主要是基於spring_session實現的分佈式集羣會話管理案例。
項目須要使用到spring_Mvc4.2.5,spring_session-1.2.2和redis-3.2.8(須要自行安裝redis服務)。
配置相關JAR包(spring mvc相關jar包依賴自行配置):
<dependency> <groupId>org.springframework.session</groupId> <artifactId>spring-session-data-redis</artifactId> <version>1.2.2.RELEASE</version> </dependency>
<?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-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <description>Spring MVC Configuration</description> <!-- 加載配置屬性文件 --> <context:property-placeholder ignore-unresolvable="true" location="classpath:config.properties" /> <!-- 使用Annotation自動註冊Bean,只掃描@Controller --> <context:component-scan base-package="com.itstyle.web" use-default-filters="false"><!-- base-package 若是多個,用「,」分隔 --> <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/> </context:component-scan> <mvc:annotation-driven/> <!--啓動Spring MVC的註解功能,設置編碼方式,防止亂碼--> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> <property name="messageConverters"> <list> <bean class = "org.springframework.http.converter.StringHttpMessageConverter"> <property name = "supportedMediaTypes"> <list> <value>text/html;charset=UTF-8</value> </list> </property> </bean> </list> </property> </bean> <!-- REST中根據URL後綴自動斷定Content-Type及相應的View --> <bean id="contentNegotiationManager" class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean"> <property name="mediaTypes" > <map> <entry key="xml" value="application/xml"/> <entry key="json" value="application/json"/> </map> </property> <property name="ignoreAcceptHeader" value="true"/> <property name="favorPathExtension" value="true"/> </bean> <!-- 定義視圖文件解析 --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="${web.view.prefix}"/> <property name="suffix" value="${web.view.suffix}"/> </bean> <!-- 對靜態資源文件的訪問, 將沒法mapping到Controller的path交給default servlet handler處理 --> <mvc:default-servlet-handler /> <!-- 靜態資源映射 SpringMVC會自動給靜態資源Response添加緩存頭Cache-Control和Expires值 cache-period="31536000"--> <mvc:resources mapping="/static/**" location="/static/" /> <!-- 定義無Controller的path<->view直接映射(首頁或者登錄頁) --> <mvc:view-controller path="/" view-name="redirect:${web.view.login}"/> </beans>
#============================# #===== System settings ======# #============================# #產品信息設置 productName=科幫網 srping session copyrightYear=2017 version=V1.0.0 #分頁配置 page.pageSize=10 #索引頁路徑 web.view.index=/index #登錄頁面 web.view.login=/login #視圖文件存放路徑 web.view.prefix=/WEB-INF/views/ web.view.suffix=.jsp #靜態文件後綴 web.staticFile=.css,.js,.png,.jpg,.gif,.jpeg,.bmp,.ico,.swf,.psd,.htc,.htm,.html,.crx,.xpi,.exe,.ipa,.apk
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd" default-autowire="byName" default-lazy-init="true"> <!-- 加載資源文件 其中包含變量信息,必須在Spring配置文件的最前面加載,即第一個加載--> <context:property-placeholder location="classpath:redis.properties" /> <!-- redis --> <bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig"/> <bean id="jedisConnectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory"> <property name="hostName" value="${redis.host}" /> <property name="port" value="${redis.port}" /> <property name="password" value="${redis.password}" /> <property name="timeout" value="${redis.timeout}" /> <property name="poolConfig" ref="jedisPoolConfig" /> <property name="usePool" value="true" /> </bean> <bean id="redisTemplate" class="org.springframework.data.redis.core.StringRedisTemplate"> <property name="connectionFactory" ref="jedisConnectionFactory" /> </bean> <!-- 將session放入redis --> <context:annotation-config/> <bean id="redisHttpSessionConfiguration" class="org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration"> <property name="maxInactiveIntervalInSeconds" value="1800" /> </bean> </beans>
#redis中心 redis.host=127.0.0.1 redis.port=6379 redis.password=123456 redis.maxIdle=100 redis.maxActive=300 redis.maxWait=1000 redis.testOnBorrow=true redis.timeout=100000
<?xml version="1.0" encoding="UTF-8"?> <web-app id="WebApp_ID" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> <display-name>spring_session</display-name> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-redis.xml</param-value> </context-param> <!-- spring session --> <filter> <filter-name>springSessionRepositoryFilter</filter-name> <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class> </filter> <filter-mapping> <filter-name>springSessionRepositoryFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <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> <servlet> <servlet-name>springServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath*:/spring-mvc*.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>springServlet</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>login</welcome-file> </welcome-file-list> </web-app>
最後,啓動項目訪問http://localhost:8080/spring_session/login
登陸redis服務,執行如下命令:
KEYS *
網上不少同窗,啓動的時候找不到 springSessionRepositoryFilter,注意在spring-redis.xml加入
參考:http://docs.spring.io/spring-session/docs/current/reference/html5/
原文:http://blog.52itstyle.com/archives/759/