T
- Java type supported by the providerpublic interface MessageBodyReader<T>
MessageBodyReader
implementation may be annotated
with Consumes
to restrict the media types for which it will
be considered suitable.
Providers implementing MessageBodyReader
contract must be either programmatically
registered in an API runtime or must be annotated with
@Provider
annotation to be automatically discovered
by the runtime during a provider scanning phase.
Modifier and Type | Method and Description |
---|---|
boolean |
isReadable(java.lang.Class<?> type,
java.lang.reflect.Type genericType,
java.lang.annotation.Annotation[] annotations,
MediaType mediaType)
Ascertain if the MessageBodyReader can produce an instance of a
particular type.
|
T |
readFrom(java.lang.Class<T> type,
java.lang.reflect.Type genericType,
java.lang.annotation.Annotation[] annotations,
MediaType mediaType,
MultivaluedMap<java.lang.String,java.lang.String> httpHeaders,
java.io.InputStream entityStream)
Read a type from the
InputStream . |
boolean isReadable(java.lang.Class<?> type, java.lang.reflect.Type genericType, java.lang.annotation.Annotation[] annotations, MediaType mediaType)
type
parameter gives the
class of the instance that should be produced, the genericType
parameter
gives the java.lang.reflect.Type
of the instance
that should be produced.
E.g. if the instance to be produced is List<String>
, the type
parameter
will be java.util.List
and the genericType
parameter will be
java.lang.reflect.ParameterizedType
.type
- the class of instance to be produced.genericType
- the type of instance to be produced. E.g. if the
message body is to be converted into a method parameter, this will be
the formal type of the method parameter as returned by
Method.getGenericParameterTypes
.annotations
- an array of the annotations on the declaration of the
artifact that will be initialized with the produced instance. E.g. if the
message body is to be converted into a method parameter, this will be
the annotations on that parameter returned by
Method.getParameterAnnotations
.mediaType
- the media type of the HTTP entity, if one is not
specified in the request then application/octet-stream
is
used.true
if the type is supported, otherwise false
.T readFrom(java.lang.Class<T> type, java.lang.reflect.Type genericType, java.lang.annotation.Annotation[] annotations, MediaType mediaType, MultivaluedMap<java.lang.String,java.lang.String> httpHeaders, java.io.InputStream entityStream) throws java.io.IOException, WebApplicationException
InputStream
.
In case the entity input stream is empty, the reader is expected to either return a
Java representation of a zero-length entity or throw a NoContentException
in case no zero-length entity representation is defined for the supported Java type.
A NoContentException
, if thrown by a message body reader while reading a server
request entity, is automatically translated by the server runtime into a BadRequestException
wrapping the original NoContentException
and rethrown for a standard processing by
the registered exception mappers
.
type
- the type that is to be read from the entity stream.genericType
- the type of instance to be produced. E.g. if the
message body is to be converted into a method parameter, this will be
the formal type of the method parameter as returned by
Method.getGenericParameterTypes
.annotations
- an array of the annotations on the declaration of the
artifact that will be initialized with the produced instance. E.g.
if the message body is to be converted into a method parameter, this
will be the annotations on that parameter returned by
Method.getParameterAnnotations
.mediaType
- the media type of the HTTP entity.httpHeaders
- the read-only HTTP headers associated with HTTP entity.entityStream
- the InputStream
of the HTTP entity. The
caller is responsible for ensuring that the input stream ends when the
entity has been consumed. The implementation should not close the input
stream.NoContentException
in case no zero-length entity representation is
defined for the supported Java type.java.io.IOException
- if an IO error arises. In case the entity input stream is empty
and the reader is not able to produce a Java representation for
a zero-length entity, NoContentException
is expected to
be thrown.WebApplicationException
- if a specific HTTP error response needs to be produced.
Only effective if thrown prior to the response being committed.