org.springframework.web.servlet.mvc.method.annotation
Class ServletModelAttributeMethodProcessor

java.lang.Object
  org.springframework.web.method.annotation.ModelAttributeMethodProcessor
      org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor

All Implemented Interfaces:

HandlerMethodArgumentResolver, HandlerMethodReturnValueHandler

public class ServletModelAttributeMethodProcessor
extends ModelAttributeMethodProcessor

A Servlet-specific ModelAttributeMethodProcessor that applies data binding through a WebDataBinder of type ServletRequestDataBinder.

Also adds a fall-back strategy to instantiate the model attribute from a URI template variable or from a request parameter if the name matches the model attribute name and there is an appropriate type conversion strategy.

Since:

3.1

Author:

Rossen Stoyanchev

Field Summary

Fields inherited from class org.springframework.web.method.annotation.ModelAttributeMethodProcessor

logger

Constructor Summary

ServletModelAttributeMethodProcessor(boolean annotationNotRequired)

Method Summary

protected void	bindRequestParameters(WebDataBinder binder, NativeWebRequest request) Extension point to bind the request to the target object.
protected Object	createAttribute(String attributeName, MethodParameter parameter, WebDataBinderFactory binderFactory, NativeWebRequest request) Instantiate the model attribute from a URI template variable or from a request parameter if the name matches to the model attribute name and if there is an appropriate type conversion strategy.
protected Object	createAttributeFromRequestValue(String sourceValue, String attributeName, MethodParameter parameter, WebDataBinderFactory binderFactory, NativeWebRequest request) Create a model attribute from a String request value (e.g.
protected String	getRequestValueForAttribute(String attributeName, NativeWebRequest request) Obtain a value from the request that may be used to instantiate the model attribute through type conversion from String to the target type.
protected Map<String,String>	getUriTemplateVariables(NativeWebRequest request)

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

handleReturnValue, isBindExceptionRequired, resolveArgument, supportsParameter, supportsReturnType, validateIfApplicable

Methods inherited from class java.lang.Object

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

Constructor Detail

ServletModelAttributeMethodProcessor

public ServletModelAttributeMethodProcessor(boolean annotationNotRequired)

Parameters:

annotationNotRequired - if "true", non-simple method arguments and return values are considered model attributes with or without a @ModelAttribute annotation.

Method Detail

createAttribute

protected final Object createAttribute(String attributeName,
                                       MethodParameter parameter,
                                       WebDataBinderFactory binderFactory,
                                       NativeWebRequest request)
                                throws Exception

Instantiate the model attribute from a URI template variable or from a request parameter if the name matches to the model attribute name and if there is an appropriate type conversion strategy. If none of these are true delegate back to the base class.

Overrides:

createAttribute in class ModelAttributeMethodProcessor

Parameters:

attributeName - the name of the attribute, never null

parameter - the method parameter

binderFactory - for creating WebDataBinder instance

request - the current request

Returns:

the created model attribute, never null

Throws:

Exception

See Also:

#createAttributeFromUriValue

getRequestValueForAttribute

protected String getRequestValueForAttribute(String attributeName,
                                             NativeWebRequest request)

Obtain a value from the request that may be used to instantiate the model attribute through type conversion from String to the target type.

The default implementation looks for the attribute name to match a URI variable first and then a request parameter.

Parameters:

attributeName - the model attribute name

request - the current request

Returns:

the request value to try to convert or null

getUriTemplateVariables

protected final Map<String,String> getUriTemplateVariables(NativeWebRequest request)

createAttributeFromRequestValue

protected Object createAttributeFromRequestValue(String sourceValue,
                                                 String attributeName,
                                                 MethodParameter parameter,
                                                 WebDataBinderFactory binderFactory,
                                                 NativeWebRequest request)
                                          throws Exception

Create a model attribute from a String request value (e.g. URI template variable, request parameter) using type conversion.

The default implementation converts only if there a registered Converter that can perform the conversion.

Parameters:

sourceValue - the source value to create the model attribute from

attributeName - the name of the attribute, never null

parameter - the method parameter

binderFactory - for creating WebDataBinder instance

request - the current request

Returns:

the created model attribute, or null

Throws:

Exception

bindRequestParameters

protected void bindRequestParameters(WebDataBinder binder,
                                     NativeWebRequest request)

Extension point to bind the request to the target object.

Downcast WebDataBinder to ServletRequestDataBinder before binding.

Overrides:

bindRequestParameters in class ModelAttributeMethodProcessor

Parameters:

binder - the data binder instance to use for the binding

request - the current request

See Also:

ServletRequestDataBinderFactory