Recommended web.xml for JSF
The file web.xml inside the WEB-INF folder is the Web Application Deployment Descriptor for your application. This is an XML file describing the servlets and other components that make up your application. The file below is what I use at work. It contains better settings than the default one, plus all descriptions of parameters.
| <?xml version="1.0" encoding="UTF-8"?> <web-app 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"> | |
| <context-param> <description> Comma separated list of URIs of (additional) faces config files. (e.g. /WEB-INF/my-config.xml) See JSF 1.0 PRD2, 10.3.2 Attention: You do not need to put /WEB-INF/faces-config.xml in here. </description> <param-name>javax.faces.CONFIG_FILES</param-name> <param-value> /WEB-INF/faces-configs/common-faces-config.xml, /WEB-INF/faces-configs/page1-faces-config.xml, /WEB-INF/faces-configs/page2-faces-config.xml </param-value> </context-param> | Follow Divide and Conquer rule: Do not put all your managed beans, navigations rules in one big file. Consider one faces-config per functions or html page. |
| <context-param> <description>State saving method: "client" or "server" (= default) See JSF Specification 2.5.3 </description> <param-name>javax.faces.STATE_SAVING_METHOD</param-name> <param-value>server</param-value> </context-param> | Server is recommended. Ive tried one day client, but HTML pages were 10Mb big! |
| <context-param> <description> Only applicable if state saving method is "server" (= default) and if org.apache.myfaces.SERIALIZE_STATE_IN_SESSION is true (=default) If true (default) the serialized state will be compressed before it is written to the session. If false the state will not be compressed. </description> <param-name> org.apache.myfaces.COMPRESS_STATE_IN_SESSION </param-name> <param-value>true</param-value> </context-param> | You should always balanced cpu/memory usage. (Compressing state cost CPU but spare memory…obvious) |
| <context-param> <description> Only applicable if state saving method is "server" (= default). If true (default) the state will be serialized to a byte stream before it is written to the session. If false the state will not be serialized to a byte stream. </description> <param-name> org.apache.myfaces.SERIALIZE_STATE_IN_SESSION </param-name> <param-value>false</param-value> </context-param> | Compressing data save memory bytes on server at the cost of more computational power. |
| <context-param> <param-name> org.apache.myfaces.NUMBER_OF_VIEWS_IN_SESSION </param-name> <param-value>5</param-value> </context-param> | Number of back button. Default is 20. far too much. reducing this value decrease memory size. |
| <context-param> <description> This parameter tells MyFaces if javascript code should be allowed in the rendered HTML output. If javascript is allowed, command_link anchors will have javascript code that submits the corresponding form. If javascript is not allowed, the state saving info and nested parameters will beadded as url parameters. Default: "true" </description> <param-name>org.apache.myfaces.ALLOW_JAVASCRIPT</param-name> <param-value>true</param-value> </context-param> <context-param> <param-name>org.apache.myfaces.DETECT_JAVASCRIPT</param-name> <param-value>false</param-value> </context-param> | Nothing special here. Most of the time, webpage are full of javascript. |
| <context-param> <description>The buffer size to set on the response when the ResponseWriter is generated. By default the value is -1, which will not assign a buffer size on the response. </description> <param-name>facelets.BUFFER_SIZE</param-name> <param-value>8192</param-value> </context-param> | Try to set the buffer size to the most common page size. |
| <context-param> <param-name>facelets.SKIP_COMMENTS</param-name> <param-value>true</param-value> </context-param> | In production, no need to let comment in rendered code |
| <context-param> <description> If true, rendered HTML code will be formatted, so that it is "human readable". i.e. additional line separators and whitespace will be written, that do not influence the HTML code. Default: "true" </description> <param-name>org.apache.myfaces.PRETTY_HTML</param-name> <param-value>false</param-value> </context-param> | Cpu waste in production. Beautify your code in eclipse. Consider instead using Firefox source chart plugin which always beautify and color the source source |
| <context-param> <description> If true, a javascript function will be rendered that is able to restore the former vertical scroll on every request. Convenient feature if you have pages with long lists and you do not want the browser page to always jump to the top if you trigger a link or button action that stays on the same page. Default: "false" </description> <param-name>org.apache.myfaces.AUTO_SCROLL</param-name> <param-value>true</param-value> </context-param> | |
| <context-param> <description> Validate managed beans, navigation rules and ensure that forms are not nested. </description> <param-name>org.apache.myfaces.VALIDATE</param-name> <param-value>true</param-value> </context-param> | Can be turned off in production, if you have a good testing team and many deployment stage This kind of errors should not go un noticed. |
| <context-param> <param-name>facelets.LIBRARIES</param-name> <param-value> /WEB-INF/taglib/tomahawk.taglib.xml; /WEB-INF/taglib/aa.taglib.xml; /WEB-INF/taglib/your.taglib.xml </param-value> </context-param> | List here all 3rd party and your own tag library |
| <context-param> <param-name>facelets.REFRESH_PERIOD</param-name> <param-value>2</param-value> </context-param> <context-param> <description>Special Debug Output for Development </description> <param-name>facelets.DEVELOPMENT</param-name> <param-value>false</param-value> </context-param> <context-param> <param-name>javax.faces.DEFAULT_SUFFIX</param-name> <param-value>.xhtml</param-value> </context-param> | Using a facelets.REFRESH_PERIOD >= 1 means that templates will be reloaded after a given period if the file has been modified on the file-system.
Obvious settings |
| <filter> <filter-name>extensionsFilter</filter-name> <filter-class> org.apache.myfaces.webapp.filter.ExtensionsFilter </filter-class> <init-param> <param-name>uploadMaxFileSize</param-name> <param-value>100m</param-value> </init-param> <init-param> <param-name>uploadThresholdSize</param-name> <param-value>100k</param-value> </init-param> </filter> | Some security settings. Consider settings these values accordingly to your needs. |
| <error-page> <error-code>404</error-code> <location>/error.jsp</location> </error-page> <error-page> <error-code>500</error-code> <location>/error.jsp</location> </error-page> <error-page> <exception-type>java.lang.Exception</exception-type> <location>/error.jsp</location> </error-page> | Standard settings not related to JSF. Never reveal any useful informations in error pages! |
