org.springframework.web.servlet.mvc.condition

Class ProducesRequestCondition

java.lang.Object

org.springframework.web.servlet.mvc.condition.AbstractRequestCondition<ProducesRequestCondition>

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

Constructors

Constructor and Description
ProducesRequestCondition(java.lang.String... produces) Creates a new instance from "produces" expressions.
ProducesRequestCondition(java.lang.String[] produces, java.lang.String[] headers) Creates a new instance with "produces" and "header" expressions.
ProducesRequestCondition(java.lang.String[] produces, java.lang.String[] headers, ContentNegotiationManager manager) Same as ProducesRequestCondition(String[], String[]) but also accepting a ContentNegotiationManager.

Method Summary

Modifier and Type	Method and Description
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 java.util.List<org.springframework.web.servlet.mvc.condition.ProducesRequestCondition.ProduceMediaTypeExpression>	getContent() Return the discrete items a request condition is composed of.
java.util.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.
java.util.Set<MediaType>	getProducibleMediaTypes() Return the contained producible media types excluding negated expressions.
protected java.lang.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(java.lang.String... produces)

Creates a new instance from "produces" expressions. If 0 expressions are provided in total, this condition will match to any request.

Parameters:

produces - expressions with syntax defined by RequestMapping.produces()

ProducesRequestCondition

public ProducesRequestCondition(java.lang.String[] produces,
                                java.lang.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, this condition will match to any request.

Parameters:

produces - expressions with syntax defined by RequestMapping.produces()

headers - expressions with syntax defined by RequestMapping.headers()

ProducesRequestCondition

public ProducesRequestCondition(java.lang.String[] produces,
                                java.lang.String[] headers,
                                ContentNegotiationManager manager)

Same as ProducesRequestCondition(String[], String[]) but also accepting a ContentNegotiationManager.

Parameters:

produces - expressions with syntax defined by RequestMapping.produces()

headers - expressions with syntax defined by RequestMapping.headers()

manager - used to determine requested media types

Method Detail

getExpressions

public java.util.Set<MediaTypeExpression> getExpressions()

Return the contained "produces" expressions.

getProducibleMediaTypes

public java.util.Set<MediaType> getProducibleMediaTypes()

Return the contained producible media types excluding negated expressions.

isEmpty

public boolean isEmpty()

Whether the condition has any media type expressions.

Overrides:

isEmpty in class AbstractRequestCondition<ProducesRequestCondition>

Returns:

true if empty; false otherwise

getContent

protected java.util.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 java.lang.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.

Returns:

a request condition instance that is the result of combining the two condition instances.

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 first index of matching media types in each "produces" condition first matching with MimeType.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.