Module org.omnifaces

Package org.omnifaces.filter

Class FacesExceptionFilter

java.lang.Object

org.omnifaces.filter.HttpFilter

org.omnifaces.filter.FacesExceptionFilter

All Implemented Interfaces:

Filter

public class FacesExceptionFilter
extends HttpFilter

The FacesExceptionFilter will solve 2 problems with exceptions thrown in Faces methods.

1. Mojarra's FacesFileNotFoundException needs to be interpreted as 404.
2. Root cause needs to be unwrapped from FacesException and ELException to utilize standard Servlet API error page handling.

Noted should be that this filter won't run on exceptions thrown during ajax requests. To handle them using web.xml configured error pages, use FullAjaxExceptionHandler.

Since version 3.2, the FacesExceptionFilter also logs exceptions with an UUID and IP via the logException(HttpServletRequest, Throwable, String, String, Object...) method. The UUID is in turn available in EL by #{requestScope['org.omnifaces.exception_uuid']}.

Installation

To get it to run, map this filter on an <url-pattern> of /* in web.xml.

 <filter>
     <filter-name>facesExceptionFilter</filter-name>
     <filter-class>org.omnifaces.filter.FacesExceptionFilter</filter-class>
 </filter>
 <filter-mapping>
     <filter-name>facesExceptionFilter</filter-name>
     <url-pattern>/*</url-pattern>
 </filter-mapping>
 

Note that since OmniFaces 4.5, the FullAjaxExceptionHandler will automatically register the FacesExceptionFilter on its default URL pattern of /* when it is absent in web.xml, so you do not need to explicitly register it then.

Error pages

Please refer the "Error pages" section of the FullAjaxExceptionHandler javadoc for recommended error page configuration.

Configuration

Please refer the "Configuration" section of the FullAjaxExceptionHandler javadoc for available context parameters.

Customizing FacesExceptionFilter

If more fine grained control is desired for logging the exception, then the developer can opt to extend this FacesExceptionFilter and override one or more of the following protected methods:

• logException(HttpServletRequest, Throwable, String, String, Object...)

Author:

Bauke Scholtz

See Also:

• FullAjaxExceptionHandler
• HttpFilter

Constructor Summary

Constructors

Constructor	Description
FacesExceptionFilter()

Method Summary

Modifier and Type	Method	Description
void	doFilter(HttpServletRequest request, HttpServletResponse response, HttpSession session, FilterChain chain)	Filter the HTTP request.
void	init()	Convenience init() method without FilterConfig parameter which will be called by init(FilterConfig).
protected void	logException(HttpServletRequest request, Throwable exception, String location, String message, Object... parameters)	Log the thrown exception and determined error page location with the given message, optionally parameterized with the given parameters.

Methods inherited from class org.omnifaces.filter.HttpFilter

destroy, doFilter, getFilterConfig, getInitParameter, getServletContext, init

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

FacesExceptionFilter

public FacesExceptionFilter()

Method Details

init

public void init()
          throws ServletException

Description copied from class: HttpFilter

Convenience init() method without FilterConfig parameter which will be called by init(FilterConfig).

Overrides:

init in class HttpFilter

Throws:

ServletException - When filter's initialization failed.

doFilter

public void doFilter(HttpServletRequest request,
 HttpServletResponse response,
 HttpSession session,
 FilterChain chain)
              throws ServletException,
IOException

Description copied from class: HttpFilter

Filter the HTTP request. The session argument is null if there is no session.

Specified by:

doFilter in class HttpFilter

Parameters:

request - The HTTP request.

response - The HTTP response.

session - The HTTP session, if any, else null.

chain - The filter chain to continue.

Throws:

ServletException - As wrapper exception when something fails in the request processing.

IOException - Whenever something fails at I/O level.

See Also:

• Filter.doFilter(ServletRequest, ServletResponse, FilterChain)

logException

protected void logException(HttpServletRequest request,
 Throwable exception,
 String location,
 String message,
 Object... parameters)

Log the thrown exception and determined error page location with the given message, optionally parameterized with the given parameters. The default implementation logs through java.util.logging as SEVERE when the thrown exception is not an instance of any type specified in context parameter "org.omnifaces.EXCEPTION_TYPES_TO_IGNORE_IN_LOGGING". The log message will be prepended with the UUID and IP address. The UUID is available in EL by #{requestScope['org.omnifaces.exception_uuid']}.

Parameters:

request - The involved servlet request.

exception - The exception to log.

location - The error page location.

message - The log message.

parameters - The log message parameters, if any. They are formatted using Formatter.

Since:

3.2