org.springframework.web.servlet.handler

Class SimpleMappingExceptionResolver

java.lang.Object

org.springframework.web.servlet.handler.AbstractHandlerExceptionResolver

org.springframework.web.servlet.handler.SimpleMappingExceptionResolver

All Implemented Interfaces:

org.springframework.core.Ordered, HandlerExceptionResolver

public class SimpleMappingExceptionResolver
extends AbstractHandlerExceptionResolver

HandlerExceptionResolver implementation that allows for mapping exception class names to view names, either for a set of given handlers or for all handlers in the DispatcherServlet.

Error views are analogous to error page JSPs, but can be used with any kind of exception including any checked one, with fine-granular mappings for specific handlers.

Since:

22.11.2003

Author:

Juergen Hoeller, Arjen Poutsma, Rossen Stoyanchev

See Also:

DispatcherServlet

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_EXCEPTION_ATTRIBUTE The default name of the exception attribute: "exception".

Fields inherited from class org.springframework.web.servlet.handler.AbstractHandlerExceptionResolver

logger

Fields inherited from interface org.springframework.core.Ordered

HIGHEST_PRECEDENCE, LOWEST_PRECEDENCE

Constructor Summary

Constructors

Constructor and Description
SimpleMappingExceptionResolver()

Method Summary

Methods

Modifier and Type	Method and Description
void	addStatusCode(String viewName, int statusCode) An alternative to setStatusCodes(Properties) for use with Java-based configuration.
protected void	applyStatusCodeIfPossible(HttpServletRequest request, HttpServletResponse response, int statusCode) Apply the specified HTTP status code to the given response, if possible (that is, if not executing within an include request).
protected Integer	determineStatusCode(HttpServletRequest request, String viewName) Determine the HTTP status code to apply for the given error view.
protected String	determineViewName(Exception ex, HttpServletRequest request) Determine the view name for the given exception, first checking against the "excludedExecptions", then searching the "exceptionMappings", and finally using the "defaultErrorView" as a fallback.
protected ModelAndView	doResolveException(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) Actually resolve the given exception that got thrown during on handler execution, returning a ModelAndView that represents a specific error page if appropriate.
protected String	findMatchingViewName(Properties exceptionMappings, Exception ex) Find a matching view name in the given exception mappings.
protected int	getDepth(String exceptionMapping, Exception ex) Return the depth to the superclass matching.
protected ModelAndView	getModelAndView(String viewName, Exception ex) Return a ModelAndView for the given view name and exception.
protected ModelAndView	getModelAndView(String viewName, Exception ex, HttpServletRequest request) Return a ModelAndView for the given request, view name and exception.
Map<String,Integer>	getStatusCodesAsMap() Returns the HTTP status codes provided via setStatusCodes(Properties).
void	setDefaultErrorView(String defaultErrorView) Set the name of the default error view.
void	setDefaultStatusCode(int defaultStatusCode) Set the default HTTP status code that this exception resolver will apply if it resolves an error view and if there is no status code mapping defined.
void	setExceptionAttribute(String exceptionAttribute) Set the name of the model attribute as which the exception should be exposed.
void	setExceptionMappings(Properties mappings) Set the mappings between exception class names and error view names.
void	setExcludedExceptions(Class<?>... excludedExceptions) Set one or more exceptions to be excluded from the exception mappings.
void	setStatusCodes(Properties statusCodes) Set the HTTP status code that this exception resolver will apply for a given resolved error view.

Methods inherited from class org.springframework.web.servlet.handler.AbstractHandlerExceptionResolver

buildLogMessage, getOrder, logException, prepareResponse, preventCaching, resolveException, setMappedHandlerClasses, setMappedHandlers, setOrder, setPreventResponseCaching, setWarnLogCategory, shouldApplyTo

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_EXCEPTION_ATTRIBUTE

public static final String DEFAULT_EXCEPTION_ATTRIBUTE

The default name of the exception attribute: "exception".

See Also:

Constant Field Values

Constructor Detail

SimpleMappingExceptionResolver

public SimpleMappingExceptionResolver()

Method Detail

setExceptionMappings

public void setExceptionMappings(Properties mappings)

Set the mappings between exception class names and error view names. The exception class name can be a substring, with no wildcard support at present. A value of "ServletException" would match javax.servlet.ServletException and subclasses, for example.

NB: Consider carefully how specific the pattern is, and whether to include package information (which isn't mandatory). For example, "Exception" will match nearly anything, and will probably hide other rules. "java.lang.Exception" would be correct if "Exception" was meant to define a rule for all checked exceptions. With more unusual exception names such as "BaseBusinessException" there's no need to use a FQN.

Parameters:

mappings - exception patterns (can also be fully qualified class names) as keys, and error view names as values

setExcludedExceptions

public void setExcludedExceptions(Class<?>... excludedExceptions)

Set one or more exceptions to be excluded from the exception mappings. Excluded exceptions are checked first and if one of them equals the actual exception, the exception will remain unresolved.

Parameters:

excludedExceptions - one or more excluded exception types

setDefaultErrorView

public void setDefaultErrorView(String defaultErrorView)

Set the name of the default error view. This view will be returned if no specific mapping was found.

Default is none.

setStatusCodes

public void setStatusCodes(Properties statusCodes)

Set the HTTP status code that this exception resolver will apply for a given resolved error view. Keys are view names; values are status codes.

Note that this error code will only get applied in case of a top-level request. It will not be set for an include request, since the HTTP status cannot be modified from within an include.

If not specified, the default status code will be applied.

See Also:

setDefaultStatusCode(int)

addStatusCode

public void addStatusCode(String viewName,
                 int statusCode)

An alternative to setStatusCodes(Properties) for use with Java-based configuration.

getStatusCodesAsMap

public Map<String,Integer> getStatusCodesAsMap()

Returns the HTTP status codes provided via setStatusCodes(Properties). Keys are view names; values are status codes.

setDefaultStatusCode

public void setDefaultStatusCode(int defaultStatusCode)

Set the default HTTP status code that this exception resolver will apply if it resolves an error view and if there is no status code mapping defined.

Note that this error code will only get applied in case of a top-level request. It will not be set for an include request, since the HTTP status cannot be modified from within an include.

If not specified, no status code will be applied, either leaving this to the controller or view, or keeping the servlet engine's default of 200 (OK).

Parameters:

defaultStatusCode - HTTP status code value, for example 500 (HttpServletResponse.SC_INTERNAL_SERVER_ERROR) or 404 (HttpServletResponse.SC_NOT_FOUND)

See Also:

setStatusCodes(Properties)

setExceptionAttribute

public void setExceptionAttribute(String exceptionAttribute)

Set the name of the model attribute as which the exception should be exposed. Default is "exception".

This can be either set to a different attribute name or to null for not exposing an exception attribute at all.

See Also:

DEFAULT_EXCEPTION_ATTRIBUTE

doResolveException

protected ModelAndView doResolveException(HttpServletRequest request,
                              HttpServletResponse response,
                              Object handler,
                              Exception ex)

Actually resolve the given exception that got thrown during on handler execution, returning a ModelAndView that represents a specific error page if appropriate.

May be overridden in subclasses, in order to apply specific exception checks. Note that this template method will be invoked after checking whether this resolved applies ("mappedHandlers" etc), so an implementation may simply proceed with its actual exception handling.

Specified by:

doResolveException in class AbstractHandlerExceptionResolver

Parameters:

request - current HTTP request

response - current HTTP response

handler - the executed handler, or null if none chosen at the time of the exception (for example, if multipart resolution failed)

ex - the exception that got thrown during handler execution

Returns:

a corresponding ModelAndView to forward to, or null for default processing

determineViewName

protected String determineViewName(Exception ex,
                       HttpServletRequest request)

Determine the view name for the given exception, first checking against the "excludedExecptions", then searching the "exceptionMappings", and finally using the "defaultErrorView" as a fallback.

Parameters:

ex - the exception that got thrown during handler execution

request - current HTTP request (useful for obtaining metadata)

Returns:

the resolved view name, or null if excluded or none found

findMatchingViewName

protected String findMatchingViewName(Properties exceptionMappings,
                          Exception ex)

Find a matching view name in the given exception mappings.

Parameters:

exceptionMappings - mappings between exception class names and error view names

ex - the exception that got thrown during handler execution

Returns:

the view name, or null if none found

See Also:

setExceptionMappings(java.util.Properties)

getDepth

protected int getDepth(String exceptionMapping,
           Exception ex)

Return the depth to the superclass matching.

0 means ex matches exactly. Returns -1 if there's no match. Otherwise, returns depth. Lowest depth wins.

determineStatusCode

protected Integer determineStatusCode(HttpServletRequest request,
                          String viewName)

Determine the HTTP status code to apply for the given error view.

The default implementation returns the status code for the given view name (specified through the statusCodes property), or falls back to the defaultStatusCode if there is no match.

Override this in a custom subclass to customize this behavior.

Parameters:

request - current HTTP request

viewName - the name of the error view

Returns:

the HTTP status code to use, or null for the servlet container's default (200 in case of a standard error view)

See Also:

setDefaultStatusCode(int), applyStatusCodeIfPossible(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, int)

applyStatusCodeIfPossible

protected void applyStatusCodeIfPossible(HttpServletRequest request,
                             HttpServletResponse response,
                             int statusCode)

Apply the specified HTTP status code to the given response, if possible (that is, if not executing within an include request).

Parameters:

request - current HTTP request

response - current HTTP response

statusCode - the status code to apply

See Also:

determineStatusCode(javax.servlet.http.HttpServletRequest, java.lang.String), setDefaultStatusCode(int), HttpServletResponse.setStatus(int)

getModelAndView

protected ModelAndView getModelAndView(String viewName,
                           Exception ex,
                           HttpServletRequest request)

Return a ModelAndView for the given request, view name and exception.

The default implementation delegates to getModelAndView(String, Exception).

Parameters:

viewName - the name of the error view

ex - the exception that got thrown during handler execution

request - current HTTP request (useful for obtaining metadata)

Returns:

the ModelAndView instance

getModelAndView

protected ModelAndView getModelAndView(String viewName,
                           Exception ex)

Return a ModelAndView for the given view name and exception.

The default implementation adds the specified exception attribute. Can be overridden in subclasses.

Parameters:

viewName - the name of the error view

ex - the exception that got thrown during handler execution

Returns:

the ModelAndView instance

See Also:

setExceptionAttribute(java.lang.String)