org.springframework.web.servlet.mvc.condition
Class ProducesRequestCondition

java.lang.Object
  extended by org.springframework.web.servlet.mvc.condition.AbstractRequestCondition<ProducesRequestCondition>
      extended by org.springframework.web.servlet.mvc.condition.ProducesRequestCondition
All Implemented Interfaces:
RequestCondition<ProducesRequestCondition>

public final class ProducesRequestCondition
extends AbstractRequestCondition<ProducesRequestCondition>

A logical disjunction (' || ') request condition to match a request's 'Accept' header to a list of media type expressions. Two kinds of media type expressions are supported, which are described in RequestMapping.produces() and RequestMapping.headers() where the header name is 'Accept'. Regardless of which syntax is used, the semantics are the same.

Since:
3.1
Author:
Arjen Poutsma, Rossen Stoyanchev

Constructor Summary
ProducesRequestCondition(String... produces)
          Creates a new instance from 0 or more "produces" expressions.
ProducesRequestCondition(String[] produces, String[] headers)
          Creates a new instance with "produces" and "header" expressions.
 
Method Summary
 ProducesRequestCondition combine(ProducesRequestCondition other)
          Returns the "other" instance if it has any expressions; returns "this" instance otherwise.
 int compareTo(ProducesRequestCondition other, HttpServletRequest request)
          Compares this and another "produces" condition as follows: Sort 'Accept' header media types by quality value via MediaType.sortByQualityValue(List) and iterate the list.
protected  List<org.springframework.web.servlet.mvc.condition.ProducesRequestCondition.ProduceMediaTypeExpression> getContent()
          Return the discrete items a request condition is composed of.
 Set<MediaTypeExpression> getExpressions()
          Return the contained "produces" expressions.
 ProducesRequestCondition getMatchingCondition(HttpServletRequest request)
          Checks if any of the contained media type expressions match the given request 'Content-Type' header and returns an instance that is guaranteed to contain matching expressions only.
 Set<MediaType> getProducibleMediaTypes()
          Return the contained producible media types excluding negated expressions.
protected  String getToStringInfix()
          The notation to use when printing discrete items of content.
 boolean isEmpty()
          Whether the condition has any media type expressions.
 
Methods inherited from class org.springframework.web.servlet.mvc.condition.AbstractRequestCondition
equals, hashCode, toString
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

ProducesRequestCondition

public ProducesRequestCondition(String... produces)
Creates a new instance from 0 or more "produces" expressions.

Parameters:
produces - expressions with the syntax described in RequestMapping.produces() if 0 expressions are provided, the condition matches to every request

ProducesRequestCondition

public ProducesRequestCondition(String[] produces,
                                String[] headers)
Creates a new instance with "produces" and "header" expressions. "Header" expressions where the header name is not 'Accept' or have no header value defined are ignored. If 0 expressions are provided in total, the condition matches to every request

Parameters:
produces - expressions with the syntax described in RequestMapping.produces()
headers - expressions with the syntax described in RequestMapping.headers()
Method Detail

getExpressions

public Set<MediaTypeExpression> getExpressions()
Return the contained "produces" expressions.


getProducibleMediaTypes

public Set<MediaType> getProducibleMediaTypes()
Return the contained producible media types excluding negated expressions.


isEmpty

public boolean isEmpty()
Whether the condition has any media type expressions.


getContent

protected List<org.springframework.web.servlet.mvc.condition.ProducesRequestCondition.ProduceMediaTypeExpression> getContent()
Description copied from class: AbstractRequestCondition
Return the discrete items a request condition is composed of. For example URL patterns, HTTP request methods, param expressions, etc.

Specified by:
getContent in class AbstractRequestCondition<ProducesRequestCondition>
Returns:
a collection of objects, never null

getToStringInfix

protected String getToStringInfix()
Description copied from class: AbstractRequestCondition
The notation to use when printing discrete items of content. For example " || " for URL patterns or " && " for param expressions.

Specified by:
getToStringInfix in class AbstractRequestCondition<ProducesRequestCondition>

combine

public ProducesRequestCondition combine(ProducesRequestCondition other)
Returns the "other" instance if it has any expressions; returns "this" instance otherwise. Practically that means a method-level "produces" overrides a type-level "produces" condition.

Parameters:
other - the condition to combine with.

getMatchingCondition

public ProducesRequestCondition getMatchingCondition(HttpServletRequest request)
Checks if any of the contained media type expressions match the given request 'Content-Type' header and returns an instance that is guaranteed to contain matching expressions only. The match is performed via MediaType.isCompatibleWith(MediaType).

Parameters:
request - the current request
Returns:
the same instance if there are no expressions; or a new condition with matching expressions; or null if no expressions match.

compareTo

public int compareTo(ProducesRequestCondition other,
                     HttpServletRequest request)
Compares this and another "produces" condition as follows:
  1. Sort 'Accept' header media types by quality value via MediaType.sortByQualityValue(List) and iterate the list.
  2. Get the lowest index of matching media types from each "produces" condition first matching with MediaType.equals(Object) and then with MediaType.includes(MediaType).
  3. If a lower index is found, the condition at that index wins.
  4. If both indexes are equal, the media types at the index are compared further with MediaType.SPECIFICITY_COMPARATOR.

It is assumed that both instances have been obtained via getMatchingCondition(HttpServletRequest) and each instance contains the matching producible media type expression only or is otherwise empty.