org.springframework.web.servlet.support

Class RequestContextUtils

java.lang.Object

org.springframework.web.servlet.support.RequestContextUtils

public abstract class RequestContextUtils
extends Object

Utility class for easy access to request-specific state which has been set by the DispatcherServlet.

Supports lookup of current WebApplicationContext, LocaleResolver, Locale, ThemeResolver, Theme, and MultipartResolver.

Since:

03.03.2003

Author:

Juergen Hoeller, Rossen Stoyanchev

See Also:

RequestContext, DispatcherServlet

Field Summary

Fields

Modifier and Type	Field and Description
static String	REQUEST_DATA_VALUE_PROCESSOR_BEAN_NAME The name of the bean to use to look up in an implementation of RequestDataValueProcessor has been configured.

Constructor Summary

Constructors

Constructor and Description
RequestContextUtils()

Method Summary

Modifier and Type	Method and Description
static WebApplicationContext	findWebApplicationContext(HttpServletRequest request) Look for the WebApplicationContext associated with the DispatcherServlet that has initiated request processing, and for the global context if none was found associated with the current request.
static WebApplicationContext	findWebApplicationContext(HttpServletRequest request, ServletContext servletContext) Look for the WebApplicationContext associated with the DispatcherServlet that has initiated request processing, and for the global context if none was found associated with the current request.
static FlashMapManager	getFlashMapManager(HttpServletRequest request) Return the FlashMapManager instance to save flash attributes.
static Map<String,?>	getInputFlashMap(HttpServletRequest request) Return read-only "input" flash attributes from request before redirect.
static Locale	getLocale(HttpServletRequest request) Retrieve the current locale from the given request, using the LocaleResolver bound to the request by the DispatcherServlet (if available), falling back to the request's accept-header Locale.
static LocaleResolver	getLocaleResolver(HttpServletRequest request) Return the LocaleResolver that has been bound to the request by the DispatcherServlet.
static FlashMap	getOutputFlashMap(HttpServletRequest request) Return "output" FlashMap to save attributes for request after redirect.
static Theme	getTheme(HttpServletRequest request) Retrieves the current theme from the given request, using the ThemeResolver and ThemeSource bound to the request by the DispatcherServlet.
static ThemeResolver	getThemeResolver(HttpServletRequest request) Return the ThemeResolver that has been bound to the request by the DispatcherServlet.
static ThemeSource	getThemeSource(HttpServletRequest request) Return the ThemeSource that has been bound to the request by the DispatcherServlet.
static TimeZone	getTimeZone(HttpServletRequest request) Retrieve the current time zone from the given request, using the TimeZoneAwareLocaleResolver bound to the request by the DispatcherServlet (if available), falling back to the system's default time zone.
static void	saveOutputFlashMap(String location, HttpServletRequest request, HttpServletResponse response) Convenience method that retrieves the "output" FlashMap, updates it with the path and query params of the target URL, and then saves it using the FlashMapManager.

Methods inherited from class java.lang.Object

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

Field Detail

REQUEST_DATA_VALUE_PROCESSOR_BEAN_NAME

public static final String REQUEST_DATA_VALUE_PROCESSOR_BEAN_NAME

The name of the bean to use to look up in an implementation of RequestDataValueProcessor has been configured.

Since:

4.2.1

See Also:

Constant Field Values

Constructor Detail

RequestContextUtils

public RequestContextUtils()

Method Detail

findWebApplicationContext

@Nullable
public static WebApplicationContext findWebApplicationContext(HttpServletRequest request,
                                                                        @Nullable
                                                                        ServletContext servletContext)

Look for the WebApplicationContext associated with the DispatcherServlet that has initiated request processing, and for the global context if none was found associated with the current request. The global context will be found via the ServletContext or via ContextLoader's current context.

NOTE: This variant remains compatible with Servlet 2.5, explicitly checking a given ServletContext instead of deriving it from the request.

Parameters:

request - current HTTP request

servletContext - current servlet context

Returns:

the request-specific WebApplicationContext, or the global one if no request-specific context has been found, or null if none

Since:

4.2.1

See Also:

DispatcherServlet.WEB_APPLICATION_CONTEXT_ATTRIBUTE, WebApplicationContextUtils.getWebApplicationContext(ServletContext), ContextLoader.getCurrentWebApplicationContext()

findWebApplicationContext

@Nullable
public static WebApplicationContext findWebApplicationContext(HttpServletRequest request)

Look for the WebApplicationContext associated with the DispatcherServlet that has initiated request processing, and for the global context if none was found associated with the current request. The global context will be found via the ServletContext or via ContextLoader's current context.

NOTE: This variant requires Servlet 3.0+ and is generally recommended for forward-looking custom user code.

Parameters:

request - current HTTP request

Returns:

the request-specific WebApplicationContext, or the global one if no request-specific context has been found, or null if none

Since:

4.2.1

See Also:

findWebApplicationContext(HttpServletRequest, ServletContext), ServletRequest.getServletContext(), ContextLoader.getCurrentWebApplicationContext()

getLocaleResolver

@Nullable
public static LocaleResolver getLocaleResolver(HttpServletRequest request)

Return the LocaleResolver that has been bound to the request by the DispatcherServlet.

Parameters:

request - current HTTP request

Returns:

the current LocaleResolver, or null if not found

getLocale

public static Locale getLocale(HttpServletRequest request)

Retrieve the current locale from the given request, using the LocaleResolver bound to the request by the DispatcherServlet (if available), falling back to the request's accept-header Locale.

This method serves as a straightforward alternative to the standard Servlet ServletRequest.getLocale() method, falling back to the latter if no more specific locale has been found.

Consider using LocaleContextHolder.getLocale() which will normally be populated with the same Locale.

Parameters:

request - current HTTP request

Returns:

the current locale for the given request, either from the LocaleResolver or from the plain request itself

See Also:

getLocaleResolver(javax.servlet.http.HttpServletRequest), LocaleContextHolder.getLocale()

getTimeZone

@Nullable
public static TimeZone getTimeZone(HttpServletRequest request)

Retrieve the current time zone from the given request, using the TimeZoneAwareLocaleResolver bound to the request by the DispatcherServlet (if available), falling back to the system's default time zone.

Note: This method returns null if no specific time zone can be resolved for the given request. This is in contrast to getLocale(javax.servlet.http.HttpServletRequest) where there is always the request's accept-header locale to fall back to.

Consider using LocaleContextHolder.getTimeZone() which will normally be populated with the same TimeZone: That method only differs in terms of its fallback to the system time zone if the LocaleResolver hasn't provided a specific time zone (instead of this method's null).

Parameters:

request - current HTTP request

Returns:

the current time zone for the given request, either from the TimeZoneAwareLocaleResolver or null if none associated

See Also:

getLocaleResolver(javax.servlet.http.HttpServletRequest), LocaleContextHolder.getTimeZone()

getThemeResolver

@Nullable
public static ThemeResolver getThemeResolver(HttpServletRequest request)

Return the ThemeResolver that has been bound to the request by the DispatcherServlet.

Parameters:

request - current HTTP request

Returns:

the current ThemeResolver, or null if not found

getThemeSource

@Nullable
public static ThemeSource getThemeSource(HttpServletRequest request)

Return the ThemeSource that has been bound to the request by the DispatcherServlet.

Parameters:

request - current HTTP request

Returns:

the current ThemeSource

getTheme

@Nullable
public static Theme getTheme(HttpServletRequest request)

Retrieves the current theme from the given request, using the ThemeResolver and ThemeSource bound to the request by the DispatcherServlet.

Parameters:

request - current HTTP request

Returns:

the current theme, or null if not found

See Also:

getThemeResolver(javax.servlet.http.HttpServletRequest)

getInputFlashMap

@Nullable
public static Map<String,?> getInputFlashMap(HttpServletRequest request)

Return read-only "input" flash attributes from request before redirect.

Parameters:

request - current request

Returns:

a read-only Map, or null if not found

See Also:

FlashMap

getOutputFlashMap

public static FlashMap getOutputFlashMap(HttpServletRequest request)

Return "output" FlashMap to save attributes for request after redirect.

Parameters:

request - current request

Returns:

a FlashMap instance, never null within a DispatcherServlet-handled request

getFlashMapManager

@Nullable
public static FlashMapManager getFlashMapManager(HttpServletRequest request)

Return the FlashMapManager instance to save flash attributes.

As of 5.0 the convenience method saveOutputFlashMap(java.lang.String, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse) may be used to save the "output" FlashMap.

Parameters:

request - the current request

Returns:

a FlashMapManager instance, never null within a DispatcherServlet-handled request

saveOutputFlashMap

public static void saveOutputFlashMap(String location,
                                      HttpServletRequest request,
                                      HttpServletResponse response)

Convenience method that retrieves the "output" FlashMap, updates it with the path and query params of the target URL, and then saves it using the FlashMapManager.

Parameters:

location - the target URL for the redirect

request - the current request

response - the current response

Since:

5.0