Servlet初始配置 监听器和过滤器

Posted shuchen007

tags:

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ServletContext:application范围内的参数

此所设定的参

数,在JSP网页中可以使用下列方法来取得:

 

${initParam.param0},

<%=application.getInitParameter("param0") %><br/>

若在Servlet可以使用下列方法来获得:

String param_name=getServletContext().getInitParameter("param0")

=this.getServletConfig().getServletContext().getInitParameter("param0")

=application.getInitParameter("param0");

使用上下文初始化参数:

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<context-param> 
           <param-name>param_name</param-name> 
           <param-value>avalible during application</param-value> 
  </context-param>
<context-param> 
    <param-name>contextConfigLocation</param-name> 
    <param-value>/WEB-INF/spring-configuration/*.xml</param-value> 
</context-param>
<wiz_tmp_tag class="wiz-block-scroll">
 

 

  部署在同一容器中的多个Web项目,要配置不同的webAppRootKey,web.xml文件中最好定义webAppRootKey参数,如果不定义,将会缺省为“webapp.root”

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    <context-param>   
        <param-name>webAppRootKey</param-name>   
        <param-value> business.root </param-value>   
    </context-param>   
<!—public-base应用路径  -->   
    <context-param>   
        <param-name>webAppRootKey</param-name>   
        <param-value> pubbase.root</param-value>   
    </context-param>

 

 

 在web.xml中该Servlet的定义标记中,比如:

servlet范围内的参数,只能在servlet的init()方法中取得(或者通过注解配置在对应的类上:@WebServlet("/MyServlet")

System.out.println(this.getInitParameter("param1")=this.getServletConfig().getInitParameter(name));

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<servlet>
     <servlet-name>TimeServlet</servlet-name>
     <servlet-class>com.allanlxf.servlet.basic.TimeServlet</servlet-class>
    <init-param>
        <param-name>param1</param-name>
        <param-value>avalible in servlet init()</param-value>
    </init-param>
    <load-on-startup>0</load-on-startup>//标记容器是否在启动的时候就加载这个servlet,执行init()方法,初始化参数</servlet>

 

配置监听器:(启动Web容器时,自动装配ApplicationContext、log4j的配置信息。)

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<context-param
    <param-name>contextConfigLocation</param-name
    <param-value>/WEB-INF/spring-configuration/*.xml</param-value
</context-param>
<context-param>  
      <param-name>log4jConfigLocation</param-name>  
      <param-value>WEB-INF/log4j.properties</param-value>  
  </context-param>  
 
  <context-param>  
      <param-name>log4jRefreshInterval</param-name>  
      <param-value>6000</param-value>  
  </context-param>   
<!-- Spring的log4j监听器 -->
<listener
    <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class
</listener
<listener
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class
</listener
<!-- 与CAS Single Sign Out Filter配合,注销登录信息  -->
<listener
<listener-class>com.yonyou.mcloud.cas.client.session.SingleSignOutHttpSessionListener</listener-class
</listener>



配置过滤器:

        Filter可认为是Servle的一种“加强版”,主要用于对用户请求request进行预处理,也可以对Response进行后处理,是个典型的处理链。使用Filter的完整流程是:Filter对用户请求进行预处理,接着将请求HttpServletRequest交给Servlet进行处理并生成响应,最后Filter再对服务器响应HttpServletResponse进行后处理。Filter与Servlet具有完全相同的生命周期,且Filter也可以通过<init-param>来配置初始化参数,获取Filter的初始化参数则使用FilterConfig的getInitParameter()。

        换种说法,Servlet里有request和response两个对象,Filter能够在一个request到达Servlet之前预处理request,也可以在离开Servlet时处理response,Filter其实是一个Servlet链。以下是Filter的一些常见应用场合,创建一个过滤器,实现Filter接口。重新init(), doFilter(), destroy().

        注解的方式配置:@WebFilter(filterName="FirstFilter",urlPatterns={"/index.jsp"},initParams={WWebInitParam(name="mood",value="awake")})

        urlPatterns:哪些URL可以过滤,默认“/*”

        initParams: 初始化哪些参数。



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<!--****************************过滤器配置*********************************-->
  <!-- 字符集过滤器 -->
  <filter
    <filter-name>CharacterEncodingFilter</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
  <!-- 单点登出过滤器 -->
  <filter
    <filter-name>CAS Single Sign Out Filter</filter-name
    <filter-class>com.yonyou.mcloud.cas.client.session.SingleSignOutFilter</filter-class
  </filter
  <!-- 认证过滤器 -->
  <filter
    <filter-name>CAS Authentication Filter</filter-name
<filter-class>com.yonyou.mcloud.cas.client.authentication.ExpandAuthenticationFilter</filter-class
    <init-param
      <param-name>casServerLoginUrl</param-name
      <param-value>https://dev.yonyou.com:443/sso-server/login</param-value
    </init-param
    <init-param
      <!--这里的server是服务端的IP -->
      <param-name>serverName</param-name
      <param-value>http://10.1.215.40:80</param-value
    </init-param
  </filter
  <!-- 验证ST/PT过滤器 -->
  <filter
    <filter-name>CAS Validation Filter</filter-name
<filter-class>org.jasig.cas.client.validation.Cas20ProxyReceivingTicketValidationFilter</filter-class
    <init-param
      <param-name>casServerUrlPrefix</param-name
      <param-value>https://dev.yonyou.com:443/sso-server</param-value
    </init-param
    <init-param
      <param-name>serverName</param-name
      <param-value>http://10.1.215.40:80</param-value
    </init-param
    <init-param
      <param-name>proxyCallbackUrl</param-name
      <param-value>https://dev.yonyou.com:443/business/proxyCallback</param-value
    </init-param
    <init-param
      <param-name>proxyReceptorUrl</param-name
      <param-value>/proxyCallback</param-value
    </init-param
    <init-param
      <param-name>proxyGrantingTicketStorageClass</param-name
<param-value>com.yonyou.mcloud.cas.client.proxy.MemcachedBackedProxyGrantingTicketStorageImpl</param-value
    </init-param
    <!-- 解决中文问题 -->
    <init-param
      <param-name>encoding</param-name
      <param-value>UTF-8</param-value
    </init-param
  </filter
  <filter
    <filter-name>CAS HttpServletRequest Wrapper Filter</filter-name
    <filter-class>org.jasig.cas.client.util.HttpServletRequestWrapperFilter</filter-class
  </filter
  <filter
    <filter-name>CAS Assertion Thread Local Filter</filter-name
    <filter-class>org.jasig.cas.client.util.AssertionThreadLocalFilter</filter-class
  </filter
  <filter
    <filter-name>NoCache Filter</filter-name
    <filter-class>com.yonyou.mcloud.cas.client.authentication.NoCacheFilter</filter-class
  </filter
  <!--****************************映射关系配置********************************-->
  <filter-mapping
    <filter-name>CharacterEncodingFilter</filter-name
    <url-pattern>/*</url-pattern
  </filter-mapping
  <filter-mapping
    <filter-name>NoCache Filter</filter-name
    <url-pattern>/*</url-pattern
  </filter-mapping
  <filter-mapping
    <filter-name>CAS Single Sign Out Filter</filter-name
    <url-pattern>/*</url-pattern
  </filter-mapping
  <filter-mapping
    <filter-name>CAS Validation Filter</filter-name
    <url-pattern>/proxyCallback</url-pattern
  </filter-mapping
  <filter-mapping
    <filter-name>CAS Authentication Filter</filter-name
    <url-pattern>/*</url-pattern
  </filter-mapping
  <filter-mapping
    <filter-name>CAS Validation Filter</filter-name
    <url-pattern>/*</url-pattern
  </filter-mapping
  <filter-mapping
    <filter-name>CAS HttpServletRequest Wrapper Filter</filter-name
    <url-pattern>/*</url-pattern
  </filter-mapping
  <filter-mapping
    <filter-name>CAS Assertion Thread Local Filter</filter-name
    <url-pattern>/*</url-pattern
  </filter-mapping>

 

 

配置失效时间:

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<session-config>  
   <session-timeout>120</session-timeout>  
</session-config>
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<welcome-file-list
    <welcome-file>index.html</welcome-file
</welcome-file-list></span>

 

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