web.xml配置文件元素详解

 1 <web-app> 2 ?3 ?????<!--定义了WEB应用的名字--> 4 ?????<display-name></display-name> 5 ?6 ?????<!--声明WEB应用的描述信息--> 7 ?????<description></description> 8 ?9 ?????<!--context-param元素声明应用范围内的初始化参数-->10 ?????<context-param></context-param>11 12 ?????<!--过滤器元素将一个名字与一个实现javax.servlet.Filter接口的类相关联-->13 ?????<filter></filter>14 15 ?????<!--一旦命名了一个过滤器，就要利用filter-mapping元素把它与一个或多个servlet或JSP页面相关联-->16 ?????<filter-mapping></filter-mapping>17 18 ?????<!--servlet API的版本2.3增加了对事件监听程序的支持，事件监听程序在建立、修改和删除会话或servlet环境时得到通知。19 ?????????Listener元素指出事件监听程序类-->20 ?????<listener></listener>21 22 ?????<!--在向servlet或JSP页面制定初始化参数或定制URL时，必须首先命名servlet或JSP页面。23 ?????????Servlet元素就是用来完成此项任务的-->24 ?????<servlet></servlet>25 26 ?????<!--服务器一般为servlet提供一个缺省的URL：http://host/webAppPrefix/servlet/ServletName。27 ?????????但是，常常会更改这个URL，以便servlet可以访问初始化参数或更容易地处理相对URL。28 ?????????在更改缺省URL时，使用servlet-mapping元素-->29 ?????<servlet-mapping></servlet-mapping>30 31 ?????<!--如果某个会话在一定时间内未被访问，服务器可以抛弃它以节省内存。可通过使用HttpSession的32 ?????????setMaxInactiveInterval方法明确设置单个会话对象的超时值，或者可利用session-config元素制定缺省超时值-->33 ?????<session-config></session-config>34 35 ?????<!--如果Web应用具有想到特殊的文件，希望能保证给他们分配特定的MIME类型，则mime-mapping元素提供这种保证-->36 ?????<mime-mapping></mime-mapping>37 38 ?????<!--指示服务器在收到引用一个目录名而不是文件名的URL时，使用哪个文件-->39 ?????<welcome-file-list></welcome-file-list>40 41 ?????<!--在返回特定HTTP状态代码时，或者特定类型的异常被抛出时，能够制定将要显示的页面-->42 ?????<error-page></error-page>43 44 ?????<!--对标记库描述符文件（Tag Libraryu Descriptor file）指定别名。此功能使你能够更改TLD文件的位置，45 ?????????而不用编辑使用这些文件的JSP页面-->46 ?????<taglib></taglib>47 48 ?????<!--声明与资源相关的一个管理对象-->49 ?????<resource-env-ref></resource-env-ref>50 51 ?????<!--声明一个资源工厂使用的外部资源-->52 ?????<resource-ref></resource-ref>53 54 ?????<!--制定应该保护的URL。它与login-config元素联合使用-->55 ?????<security-constraint></security-constraint>56 57 ?????<!--指定服务器应该怎样给试图访问受保护页面的用户授权。它与sercurity-constraint元素联合使用-->58 ?????<login-config></login-config>59 60 ?????<!--给出安全角色的一个列表，这些角色将出现在servlet元素内的security-role-ref元素的role-name子元素中。61 ?????????分别地声明角色可使高级IDE处理安全信息更为容易-->62 ?????<security-role></security-role>63 64 ?????<!--声明Web应用的环境项-->65 ?????<env-entry></env-entry>66 67 ?????<!--声明一个EJB的主目录的引用-->68 ?????<ejb-ref></ejb-ref>69 70 ?????<!--声明一个EJB的本地主目录的应用-->71 ?????<ejb-local-ref></ejb-local-ref>72 73 ?</web-app> 

1 <icon> ?2 ?????<small-icon>/images/app_small.gif</small-icon> ?3 ?????<large-icon>/images/app_large.gif</large-icon> ?4 ?</icon>

<display-name>Tomcat Example</display-name>

<desciption>Tomcat Example servlets and JSP pages.</desciption>

1 <context-param>2 ?????<param-name>参数名</para-name>3 ?????<param-value>参数值</param-value>4 ?????<description>参数描述</description>5 ?</context-param>

 1 <filter> 2 ?????<filter-name>setCharacterEncoding</filter-name> 3 ?????<filter-class>com.myTest.setCharacterEncodingFilter</filter-class> 4 ?????<init-param> 5 ?????????<param-name>encoding</param-name> 6 ?????????<param-value>GB2312</param-value> 7 ?????</init-param> 8 ?</filter> 9 ?<filter-mapping>10 ?????<filter-name>setCharacterEncoding</filter-name>11 ?????<url-pattern>/*</url-pattern>12 ?</filter-mapping>

1 <listener>2 ?????<listerner-class>org.springframework.web.context.ContextLoaderListener</listener-class>3 ?</listener>

 1 <servlet> 2 ???<servlet-name>servlet名称</servlet-name> 3 ???<servlet-class>servlet类全路径</servlet-class> 4 ???<init-param> 5 ???????<param-name>参数名</param-name> 6 ???????<param-value>参数值</param-value> 7 ???</init-param> 8 ???<run-as> 9 ???????<description>Security role for anonymous access</description>10 ???????<role-name>tomcat</role-name>11 ???</run-as>12 　 <load-on-startup>指定当Web应用启动时，装载Servlet的次序</load-on-startup>13 </servlet>14 <servlet-mapping>15 ??<servlet-name>servlet名称</servlet-name>16 ??<url-pattern>映射路径</url-pattern>17 </servlet-mapping>

1 <session-config>2 ?????<session-timeout>120</session-timeout>3 ?</session-config>

1 <mime-mapping>2 ?????<extension>htm</extension>3 ?????<mime-type>text/html</mime-type>4 ?</mime-mapping>

1 ?<welcome-file-list>2 ?????<welcome-file>index.jsp</welcome-file>3 ?????<welcome-file>index.html</welcome-file>4 ?????<welcome-file>index.htm</welcome-file>5 ?</welcome-file-list>

1 <!--配置了当系统发生404错误时，跳转到错误处理页面NotFound.jsp-->2 <error-page>3 ??????<error-code>404</error-code>4 ??????<location>/NotFound.jsp</location>5 ?</error-page>

1 <!--配置了当系统发生java.lang.NullException（即空指针异常）时，跳转到错误处理页面error.jsp-->2 <error-page>3 ??????<exception-type>java.lang.NullException</exception-type>4 ??????<location>/error.jsp</location>5 </error-page>

1 <taglib>2 ?????<taglib-uri>http://jakarta.apache.org/tomcat/debug-taglib</taglib-uri>3 ?????<taglib-location>/WEB-INF/jsp/debug-taglib.tld</taglib-location>4 ?</taglib>

1 <jsp-config>2 ?????<taglib>3 ?????????<taglib-uri>http://jakarta.apache.org/tomcat/debug-taglib</taglib-uri>4 ?????????<taglib-location>/WEB-INF/pager-taglib.tld</taglib-location>5 ?????</taglib>6 ?</jsp-config>

1 <resource-env-ref>2 ?????<resource-env-ref-name>jms/StockQueue</resource-env-ref-name>3 ?</resource-env-ref>

1 <resource-ref>2 ?????<res-ref-name>mail/Session</res-ref-name>3 ?????<res-type>javax.mail.Session</res-type>4 ?????<res-auth>Container</res-auth>5 </resource-ref>

1 ?<resource-ref>2 ?????<description>JNDI JDBC DataSource of shop</description>3 ?????<res-ref-name>jdbc/sample_db</res-ref-name>4 ?????<res-type>javax.sql.DataSource</res-type>5 ?????<res-auth>Container</res-auth>6 ?</resource-ref>

 1 <security-constraint> 2 ?????<display-name>Example Security Constraint</display-name> 3 ?????<web-resource-collection> 4 ?????????<web-resource-name>Protected Area</web-resource-name> 5 ?????????<url-pattern>/jsp/security/protected/*</url-pattern> 6 ?????????<http-method>DELETE</http-method> 7 ?????????<http-method>GET</http-method> 8 ?????????<http-method>POST</http-method> 9 ?????????<http-method>PUT</http-method>10 ?????</web-resource-collection>11 ?????<auth-constraint>12 ?????????<role-name>tomcat</role-name>13 ?????????<role-name>role1</role-name>14 ?????</auth-constraint>15 </security-constraint>

1 ?<login-config>2 ?????<auth-method>FORM</auth-method>3 ?????<realm-name>Example-Based Authentiation Area</realm-name>4 ?????<form-login-config>5 ?????????<form-login-page>/jsp/security/protected/login.jsp</form-login-page>6 ?????????<form-error-page>/jsp/security/protected/error.jsp</form-error-page>7 ?????</form-login-config>8 ?</login-config>

1 <security-role>2 ?????<role-name>tomcat</role-name>3 ?</security-role>

1 <env-entry>2 ?????<env-entry-name>minExemptions</env-entry-name>3 ?????<env-entry-value>1</env-entry-value>4 ?????<env-entry-type>java.lang.Integer</env-entry-type>5 </env-entry>

1 <ejb-ref>2 ?????<description>Example EJB reference</decription>3 ?????<ejb-ref-name>ejb/Account</ejb-ref-name>4 ?????<ejb-ref-type>Entity</ejb-ref-type>5 ?????<home>com.mycompany.mypackage.AccountHome</home>6 ?????<remote>com.mycompany.mypackage.Account</remote>7 ?</ejb-ref>

1 ?<ejb-local-ref>2 ?????<description>Example Loacal EJB reference</decription>3 ?????<ejb-ref-name>ejb/ProcessOrder</ejb-ref-name>4 ?????<ejb-ref-type>Session</ejb-ref-type>5 ?????<local-home>com.mycompany.mypackage.ProcessOrderHome</local-home>6 ?????<local>com.mycompany.mypackage.ProcessOrder</local>7 ?</ejb-local-ref>