public final class FacesServlet extends Object implements Servlet
FacesServlet is a servlet that manages the request processing lifecycle for web applications that are utilizing JavaServer Faces to construct the user interface.
If the application is running in a Servlet 3.0 (and beyond) container, the runtime must provide an implementation of the ServletContainerInitializer interface that declares the following classes in its HandlesTypes annotation.
ResourceDependenciesResourceDependencyFacesComponentUIComponentConverterFacesConverterListenerForListenersForFacesBehaviorRendererRendererFacesValidatorValidatorThis servlet must automatically be mapped if it is not explicitly mapped in web.xml or web-fragment.xml and one or more of the following conditions are true.
A faces-config.xml file is found in WEB-INF
A faces-config.xml file is found in the META-INF directory of a jar in the application's classpath.
A filename ending in .faces-config.xml is found in the META-INF directory of a jar in the application's classpath.
The javax.faces.CONFIG_FILES context param is declared in web.xml or web-fragment.xml.
The Set of classes passed to the onStartup() method of the ServletContainerInitializer implementation is not empty.
If the runtime determines that the servlet must be automatically mapped, it must be mapped to the following <url-pattern> entries.
This class must be annotated with javax.servlet.annotation.MultipartConfig. This causes the Servlet container in which the JSF implementation is running to correctly handle multipart form data.
Some security considerations relating to this class
The topic of web application security is a cross-cutting concern and every aspect of the specification address it. However, as with any framework, the application developer needs to pay careful attention to security. Please consider these topics among the rest of the security concerns for the application. This is by no means a complete list of security concerns, and is no substitute for a thorough application level security review.
Prefix mappings and the FacesServlet
If the FacesServlet is mapped using a prefix <url-pattern>, such as <url-pattern>/faces/*</url-pattern>, something must be done to prevent access to the view source without its first being processed by the FacesServlet. One common approach is to apply a <security-constraint> to all facelet files and flow definition files. Please see the Deployment Descriptor chapter of the Java Servlet Specification for more information the use of <security-constraint>.
Allowable HTTP Methods
The JSF specification only requires the use of the GET and POST http methods. If your web application does not require any other http methods, such as PUT and DELETE, please consider restricting the allowable http methods using the <http-method> and <http-method-omission> elements. Please see the Security of the Java Servlet Specification for more information the use of these elements.
| Modifier and Type | Field and Description |
|---|---|
static String | CONFIG_FILES_ATTR Context initialization parameter name for a comma delimited list of context-relative resource paths (in addition to /WEB-INF/faces-config.xml which is loaded automatically if it exists) containing JavaServer Faces configuration information. |
static String | LIFECYCLE_ID_ATTR Context initialization parameter name for the lifecycle identifier of the Lifecycle instance to be utilized. |
| Constructor and Description |
|---|
FacesServlet() |
| Modifier and Type | Method and Description |
|---|---|
void | destroy() Release all resources acquired at startup time. |
ServletConfig | getServletConfig() Return the ServletConfig instance for this servlet. |
String | getServletInfo() Return information about this Servlet. |
void | init(ServletConfig servletConfig) Acquire the factory instances we will require. |
void | service(ServletRequest req, ServletResponse resp) Process an incoming request, and create the corresponding response according to the following specification. |
public static final String CONFIG_FILES_ATTR
Context initialization parameter name for a comma delimited list of context-relative resource paths (in addition to /WEB-INF/faces-config.xml which is loaded automatically if it exists) containing JavaServer Faces configuration information.
public static final String LIFECYCLE_ID_ATTR
Context initialization parameter name for the lifecycle identifier of the Lifecycle instance to be utilized.
public void destroy()
Release all resources acquired at startup time.
public ServletConfig getServletConfig()
Return the ServletConfig instance for this servlet.
getServletConfig in interface ServletServletConfig object that initializes this servletServlet.init(javax.servlet.ServletConfig)public String getServletInfo()
Return information about this Servlet.
getServletInfo in interface ServletString containing servlet informationpublic void init(ServletConfig servletConfig) throws ServletException
Acquire the factory instances we will require.
init in interface ServletservletConfig - a ServletConfig object containing the servlet's configuration and initialization parametersServletException - if, for any reason, the startup of this Faces application failed. This includes errors in the config file that is parsed before or during the processing of this init() method.UnavailableException, Servlet.getServletConfig()public void service(ServletRequest req, ServletResponse resp) throws IOException, ServletException
Process an incoming request, and create the corresponding response according to the following specification.
If the request and response arguments to this method are not instances of HttpServletRequest and HttpServletResponse, respectively, the results of invoking this method are undefined.
This method must respond to requests that contain the following strings by invoking the sendError method on the response argument (cast to HttpServletResponse), passing the code HttpServletResponse.SC_NOT_FOUND as the argument.
/WEB-INF/ /WEB-INF /META-INF/ /META-INF If none of the cases described above in the specification for this method apply to the servicing of this request, the following action must be taken to service the request.
Acquire a FacesContext instance for this request.
Acquire the ResourceHandler for this request by calling Application.getResourceHandler(). Call ResourceHandler.isResourceRequest(javax.faces.context.FacesContext). If this returns true call ResourceHandler.handleResourceRequest(javax.faces.context.FacesContext). If this returns false, call Lifecycle.attachWindow(javax.faces.context.FacesContext) followed by Lifecycle.execute(javax.faces.context.FacesContext) followed by Lifecycle.render(javax.faces.context.FacesContext). If a FacesException is thrown in either case, extract the cause from the FacesException. If the cause is null extract the message from the FacesException, put it inside of a new ServletException instance, and pass the FacesException instance as the root cause, then rethrow the ServletException instance. If the cause is an instance of ServletException, rethrow the cause. If the cause is an instance of IOException, rethrow the cause. Otherwise, create a new ServletException instance, passing the message from the cause, as the first argument, and the cause itself as the second argument.
The implementation must make it so FacesContext.release() is called within a finally block as late as possible in the processing for the JSF related portion of this request.
service in interface Servletreq - The servlet request we are processingresp - The servlet response we are creatingIOException - if an input/output error occurs during processingServletException - if a servlet error occurs during processingCopyright © 1996-2015, Oracle and/or its affiliates. All Rights Reserved. Use is subject to license terms.