javax.ws.rs.core
Interface Request

All Known Implementing Classes:
RequestImpl

public interface Request

An injectable helper for request processing, all methods throw java.lang.IllegalStateException if called outside the scope of a request (e.g. from a provider constructor).

Precondition processing (see the evaluatePreconditions methods) can result in either a null return value to indicate that preconditions have been met and that the request should continue, or a non-null return value to indicate that preconditions were not met. In the event that preconditions were not met, the returned ResponseBuilder instance will have an appropriate status and will also include a Vary header if the selectVariant(java.util.List) method was called prior to to calling evaluatePreconditions. It is the responsibility of the caller to check the status and add additional metadata if required. E.g., see HTTP/1.1, section 10.3.5 for details of the headers that are expected to accompany a 304 Not Modified response.


Method Summary
 Response.ResponseBuilder evaluatePreconditions()
          Evaluate request preconditions for a resource that does not currently exist.
 Response.ResponseBuilder evaluatePreconditions(java.util.Date lastModified)
          Evaluate request preconditions based on the passed in value.
 Response.ResponseBuilder evaluatePreconditions(java.util.Date lastModified, EntityTag eTag)
          Evaluate request preconditions based on the passed in value.
 Response.ResponseBuilder evaluatePreconditions(EntityTag eTag)
          Evaluate request preconditions based on the passed in value.
 java.lang.String getMethod()
          Get the request method, e.g.
 Variant selectVariant(java.util.List<Variant> variants)
          Select the representation variant that best matches the request.
 

Method Detail

getMethod

java.lang.String getMethod()
Get the request method, e.g. GET, POST, etc.

Returns:
the request method
See Also:
HttpMethod

selectVariant

Variant selectVariant(java.util.List<Variant> variants)
                      throws java.lang.IllegalArgumentException
Select the representation variant that best matches the request. More explicit variants are chosen ahead of less explicit ones. A vary header is computed from the supplied list and automatically added to the response.

Parameters:
variants - a list of Variant that describe all of the available representation variants.
Returns:
the variant that best matches the request.
Throws:
java.lang.IllegalArgumentException - if variants is empty or null
java.lang.IllegalStateException - if called outside the scope of a request
See Also:
Variant.VariantListBuilder

evaluatePreconditions

Response.ResponseBuilder evaluatePreconditions(EntityTag eTag)
Evaluate request preconditions based on the passed in value.

Parameters:
eTag - an ETag for the current state of the resource
Returns:
null if the preconditions are met or a ResponseBuilder set with the appropriate status if the preconditions are not met. A returned ResponseBuilder will include an ETag header set with the value of eTag.
Throws:
java.lang.IllegalArgumentException - if eTag is null
java.lang.IllegalStateException - if called outside the scope of a request

evaluatePreconditions

Response.ResponseBuilder evaluatePreconditions(java.util.Date lastModified)
Evaluate request preconditions based on the passed in value.

Parameters:
lastModified - a date that specifies the modification date of the resource
Returns:
null if the preconditions are met or a ResponseBuilder set with the appropriate status if the preconditions are not met.
Throws:
java.lang.IllegalArgumentException - if lastModified is null
java.lang.IllegalStateException - if called outside the scope of a request

evaluatePreconditions

Response.ResponseBuilder evaluatePreconditions(java.util.Date lastModified,
                                               EntityTag eTag)
Evaluate request preconditions based on the passed in value.

Parameters:
lastModified - a date that specifies the modification date of the resource
eTag - an ETag for the current state of the resource
Returns:
null if the preconditions are met or a ResponseBuilder set with the appropriate status if the preconditions are not met. A returned ResponseBuilder will include an ETag header set with the value of eTag.
Throws:
java.lang.IllegalArgumentException - if lastModified or eTag is null
java.lang.IllegalStateException - if called outside the scope of a request

evaluatePreconditions

Response.ResponseBuilder evaluatePreconditions()
Evaluate request preconditions for a resource that does not currently exist. The primary use of this method is to support the If-Match: * and If-None-Match: * preconditions.

Note that both preconditions If-None-Match: * and If-None-Match: something will always be considered to have been met and it is the applications responsibility to enforce any additional method-specific semantics. E.g. a PUT on a resource that does not exist might succeed whereas a GET on a resource that does not exist would likely result in a 404 response. It would be the responsibility of the application to generate the 404 response.

Returns:
null if the preconditions are met or a ResponseBuilder set with the appropriate status if the preconditions are not met.
Throws:
java.lang.IllegalStateException - if called outside the scope of a request


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