Package org.springframework.web.servlet.mvc.method.annotation

Class PathVariableMethodArgumentResolver

java.lang.Object

org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver

org.springframework.web.servlet.mvc.method.annotation.PathVariableMethodArgumentResolver

All Implemented Interfaces:

HandlerMethodArgumentResolver, UriComponentsContributor

public class PathVariableMethodArgumentResolver
extends AbstractNamedValueMethodArgumentResolver
implements UriComponentsContributor

Resolves method arguments annotated with an @PathVariable.

An @PathVariable is a named value that gets resolved from a URI template variable. It is always required and does not have a default value to fall back on. See the base class AbstractNamedValueMethodArgumentResolver for more information on how named values are processed.

If the method parameter type is Map, the name specified in the annotation is used to resolve the URI variable String value. The value is then converted to a Map via type conversion, assuming a suitable Converter or PropertyEditor has been registered.

A WebDataBinder is invoked to apply type conversion to resolved path variable values that don't yet match the method parameter type.

Since:

3.1

Author:

Rossen Stoyanchev, Arjen Poutsma, Juergen Hoeller

Nested Class Summary

Nested classes/interfaces inherited from class org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver

AbstractNamedValueMethodArgumentResolver.NamedValueInfo

Constructor Summary

Constructors

Constructor	Description
PathVariableMethodArgumentResolver()

Method Summary

Modifier and Type	Method	Description
void	contributeMethodArgument(MethodParameter parameter, Object value, UriComponentsBuilder builder, Map<String,Object> uriVariables, ConversionService conversionService)	Process the given method argument and either update the UriComponentsBuilder or add to the map with URI variables to use to expand the URI after all arguments are processed.
protected AbstractNamedValueMethodArgumentResolver.NamedValueInfo	createNamedValueInfo(MethodParameter parameter)	Create the AbstractNamedValueMethodArgumentResolver.NamedValueInfo object for the given method parameter.
protected @Nullable String	formatUriValue(@Nullable ConversionService cs, @Nullable TypeDescriptor sourceType, Object value)
protected void	handleMissingValue(String name, MethodParameter parameter)	Invoked when a named value is required, but AbstractNamedValueMethodArgumentResolver.resolveName(String, MethodParameter, NativeWebRequest) returned null and there is no default value.
protected void	handleMissingValueAfterConversion(String name, MethodParameter parameter, NativeWebRequest request)	Invoked when a named value is present but becomes null after conversion.
protected void	handleResolvedValue(@Nullable Object arg, String name, MethodParameter parameter, @Nullable ModelAndViewContainer mavContainer, NativeWebRequest request)	Invoked after a value is resolved.
protected @Nullable Object	resolveName(String name, MethodParameter parameter, NativeWebRequest request)	Resolve the given parameter type and value name into an argument value.
boolean	supportsParameter(MethodParameter parameter)	Whether this contributor supports the given method parameter.

Methods inherited from class org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver

handleMissingValue, resolveArgument

Methods inherited from class java.lang.Object

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

Constructor Details

PathVariableMethodArgumentResolver

public PathVariableMethodArgumentResolver()

Method Details

supportsParameter

public boolean supportsParameter(MethodParameter parameter)

Description copied from interface: UriComponentsContributor

Whether this contributor supports the given method parameter.

Specified by:

supportsParameter in interface HandlerMethodArgumentResolver

Specified by:

supportsParameter in interface UriComponentsContributor

Parameters:

parameter - the method parameter to check

Returns:

true if this resolver supports the supplied parameter; false otherwise

createNamedValueInfo

protected AbstractNamedValueMethodArgumentResolver.NamedValueInfo createNamedValueInfo(MethodParameter parameter)

Description copied from class: AbstractNamedValueMethodArgumentResolver

Create the AbstractNamedValueMethodArgumentResolver.NamedValueInfo object for the given method parameter. Implementations typically retrieve the method annotation by means of MethodParameter.getParameterAnnotation(Class).

Specified by:

createNamedValueInfo in class AbstractNamedValueMethodArgumentResolver

Parameters:

parameter - the method parameter

Returns:

the named value information

resolveName

protected @Nullable Object resolveName(String name,
 MethodParameter parameter,
 NativeWebRequest request)
                                throws Exception

Description copied from class: AbstractNamedValueMethodArgumentResolver

Resolve the given parameter type and value name into an argument value.

Specified by:

resolveName in class AbstractNamedValueMethodArgumentResolver

Parameters:

name - the name of the value being resolved

parameter - the method parameter to resolve to an argument value (pre-nested in case of a Optional declaration)

request - the current request

Returns:

the resolved argument (may be null)

Throws:

Exception - in case of errors

handleMissingValue

protected void handleMissingValue(String name,
 MethodParameter parameter)
                           throws ServletRequestBindingException

Description copied from class: AbstractNamedValueMethodArgumentResolver

Invoked when a named value is required, but AbstractNamedValueMethodArgumentResolver.resolveName(String, MethodParameter, NativeWebRequest) returned null and there is no default value. Subclasses typically throw an exception in this case.

Overrides:

handleMissingValue in class AbstractNamedValueMethodArgumentResolver

Parameters:

name - the name for the value

parameter - the method parameter

Throws:

ServletRequestBindingException

handleMissingValueAfterConversion

protected void handleMissingValueAfterConversion(String name,
 MethodParameter parameter,
 NativeWebRequest request)
                                          throws Exception

Description copied from class: AbstractNamedValueMethodArgumentResolver

Invoked when a named value is present but becomes null after conversion.

Overrides:

handleMissingValueAfterConversion in class AbstractNamedValueMethodArgumentResolver

Parameters:

name - the name for the value

parameter - the method parameter

request - the current request

Throws:

Exception

handleResolvedValue

protected void handleResolvedValue(@Nullable Object arg,
 String name,
 MethodParameter parameter,
 @Nullable ModelAndViewContainer mavContainer,
 NativeWebRequest request)

Description copied from class: AbstractNamedValueMethodArgumentResolver

Invoked after a value is resolved.

Overrides:

handleResolvedValue in class AbstractNamedValueMethodArgumentResolver

Parameters:

arg - the resolved argument value

name - the argument name

parameter - the argument parameter type

mavContainer - the ModelAndViewContainer (may be null)

request - the current request

contributeMethodArgument

public void contributeMethodArgument(MethodParameter parameter,
 Object value,
 UriComponentsBuilder builder,
 Map<String,Object> uriVariables,
 ConversionService conversionService)

Description copied from interface: UriComponentsContributor

Process the given method argument and either update the UriComponentsBuilder or add to the map with URI variables to use to expand the URI after all arguments are processed.

Specified by:

contributeMethodArgument in interface UriComponentsContributor

Parameters:

parameter - the controller method parameter (never null)

value - the argument value (possibly null)

builder - the builder to update (never null)

uriVariables - a map to add URI variables to (never null)

conversionService - a ConversionService to format values as Strings

formatUriValue

protected @Nullable String formatUriValue(@Nullable ConversionService cs,
 @Nullable TypeDescriptor sourceType,
 Object value)