Draft of the JAX-RS 2.0 JSR

From: Roberto Chinnici <>
Date: Thu, 11 Nov 2010 16:24:09 -0800


Below you'll find a draft of the JAX-RS 2.0 JSR. Since JAX-RS 1.1
closed, we've been interacting with many of you in the community, at
conferences and across various forums, so hopefully you won't find any
surprising items in this draft.

Please send us your comments/suggestions in the next couple of weeks. In
parallel, we'll be working on filling in the remaining sections marked
as TBD, including the schedule and business terms. We'd like to submit
the JSR in early December, so as to get it approved by the JCP Executive
Committee ahead of the year-end holidays.

Please let us know if you'd like to be listed as a supporter of this JSR.

Roberto & Paul



JAX-RS 2.0: The Java(TM) API for RESTful Web Services 2.0


This JSR will develop the next version of JAX-RS, the API for for
RESTful (Representational State Transfer) Web Services in the Java Platform.

Section 1: Identification

JCP Member submitting this proposal: Oracle Corporation

Name of Contact Person: Roberto Chinnici
E-Mail Address:
Telephone Number: +1 (415) 402-7873
Fax Number: +1 (415) 402-7215

Name of Specification Lead: Roberto Chinnici
E-Mail Address:
Telephone Number: +1 (415) 402-7873
Fax Number: +1 (415) 402-7215

Name of Specification Lead: Paul Sandoz
E-Mail Address:
Telephone Number: +33476188109
Fax Number: N/A

Initial Group Membership:


Supporting this JSR:


Section 2: Request

2.1 Please describe the proposed Specification:

The most commonly requested feature for JAX-RS 2.0 is a client API: many
if not all JAX-RS implementations provide some degree of client API
support. This JSR will define two client APIs, both compatible with the
REST style: a low level API using a builder pattern and a higher level
one leveraging the former. Common security mechanisms will also be
specified. The API will not define how HTTP client implementations, such
as HttpUrlConnection or the Apache HTTP client library, will plug into
the API. The API will support synchronous and asynchronous response
processing. WebSocket or HTTP streaming processing of responses are out
of scope for this JSR and will be handled in a future revision of JAX-RS.

Hypermedia is a very important feature of RESTful Web applications.
JAX-RS 1.1 provided some basic support for building URIs but this JSR
will define a way to easily create and process links associated with
resources in representations either as link headers or links within the
entity body. Similarly, on the client it will be possible to extract
links in representations and make further requests according to those links.

Model-View-Controller (MVC) is a common pattern in Web frameworks, where
it is used predominantly by HTML-based applications. Adopting the MVC
terminology, JAX-RS resource classes are comparable to controllers. This
JSR will specify an MVC architecture compatible with the JAX-RS
programing model. Java Server Pages will be specified as one type of
view. It will be possible to plug in other view technologies, for
example FreeMarker or StringTemplate.

JAX-RS 1.1 has limited support for parameter validation. This JSR will
make it possible to validate a set of parameters, such as form or query
parameters, and to return a meaningful response in case validation
fails. The primary API utilized for validation will be the Bean
Validation API.

JAX-RS 1.1 was defined before JSR-330 was specified and as a result does
not utilize 330 annotations, such as @Inject, as effectively as it
could. This JSR will specify closer integration with 330 annotations
that may potentially render some existing annotations in JAX-RS, such as
@Context, deprecated or redundant.

JAX-RS 1.1 defines a synchronous request response model on the server
side. This JSR will specify a simple asynchronous request processing
model such that a response can be returned asynchronous to the request.
Servlet 3.0 can be leveraged to enable such support but implementations
may choose to use other container-specific APIs instead.

In JAX-RS 1.1, content negotiation is primarily driven by the client
using the "q" parameter in the Accept header. This JSR will add support
for a server-side equivalent of it, "qs", to give the server more saying
in the selected representation; the algorithm for content negotiation in
the existing JAX-RS specification will be update so as to maintain
determinism and compatibility across implementations.

This JSR will also make improvements to JSR in the area of ease of use,
e.g. by following the do-not-repeat-yourself principle more closely. It
will also fix any number of bugs discovered in JAX-RS 1.1.

As mentioned above, asynchronous support for HTTP long polling, Comet
and Web Sockets is out of scope for this release. We plan to address it
in a future revision of the JAX-RS specification.

2.2 What is the target Java platform? (i.e., desktop, server, personal,
embedded, card, etc.)

This specification is targeted for Java SE 6.0 or higher and Java EE 6
or higher platforms.

2.3 The Executive Committees would like to ensure JSR submitters think
about how their proposed technology relates to all of the Java platform
editions. Please provide details here for which platform editions are
being targeted by this JSR, and how this JSR has considered the
relationship with the other platform editions.

This JSR is targeted for inclusion in the Java EE 7 platform.
Additionally, Java EE 6 products will be allowed to implement JAX-RS 2.0
instead of JAX-RS 1.1.

2.4 Should this JSR be voted on by both Executive Committees?

No. By the SE/EE EC only.

2.5 What need of the Java community will be addressed by the proposed

See 2.1 above.

2.6 Why isn't this need met by existing specifications?

See 2.1 above.

2.7 Please give a short description of the underlying technology or

See above.

2.8 Is there a proposed package name for the API Specification? (i.e.,
javapi.something, org.something, etc.)

JAX-RS 2.0 will use the same package name as JAX-RS 1.1, namely

2.9 Does the proposed specification have any dependencies on specific
operating systems, CPUs, or I/O devices that you know of?


2.10 Are there any security issues that cannot be addressed by the
current security model?

No. This JSR will leverage existing HTTP security mechanisms.

2.11 Are there any internationalization or localization issues?

This JSR will use the I18N support in Java SE.

2.12 Are there any existing specifications that might be rendered
obsolete, deprecated, or in need of revision as a result of this work?


2.13 Please describe the anticipated schedule for the development of
this specification.


2.14 Please describe the anticipated working model for the Expert Group
working on developing this specification.

The primary means of communication will be email, with conference calls
and face-to-face meetings scheduled as needed. We will solicit feedback
from the community and leverage the open source development model.

2.15 Provide detailed answers to the transparency checklist, making sure
to include URLs as appropriate.

JAX-RS 2.0 will follow the same working model as JAX-RS 1.0/1.1
(JSR-311). In particular, a project site will be used to track all
issues and disseminate information on the progress of the JSR. See for more details on the way JAX-RS 1.0 was run.

- The public can read the names of the people on the Expert Group.

This information will be on on the project page for the JSR. It will
also be part of every specification draft.

- The Expert Group business is regularly reported on a publicly readable

The Expert Group will conduct business on a publicly readable alias. A
private alias will be used only for EG-confidential information, as needed.

- The schedule for the JSR is publicly available, it's current, and I
update it regularly.

The schedule will be available on the project page for the JSR.

- The public can read/write to a wiki for my JSR.

We'll use a public mailing list for comments.

- I read and respond to posts on the discussion board for my JSR on

We'll track such discussions and respond to them or redirect users to
the public comment mailing list.

- There is an issue-tracker for my JSR that the public can read.

Yes, it will be accessible from the JSR project page.

- I have spoken at conferences and events about my JSR recently.

Yes, most recently at JavaOne 2010 and Devoxx 2010.

- I am using open-source processes for the development of the RI and/or TCK.

Yes, as Project Jersey, see

- The Update tab for my JSR has links to and information about all
public communication mechanisms and sites for the development of my JSR.

It will point to the project page for the JSR.

2.16 Please describe how the RI and TCK will de delivered, i.e. as part
of a profile or platform edition, or stand-alone, or both. Include
version information for the profile or platform in your answer.

The reference implementation will be made available standalone and also
as part of the reference implementation for the Java EE 7 platform. The
TCK will be made available standalone as part of the Java EE CTS.

2.17 Please state the rationale if previous versions are available
stand-alone and you are now proposing in 2.13 to only deliver RI and TCK
as part of a profile or platform edition (See sections 1.1.5 and 1.1.6
of the JCP 2 document).


2.18 Please provide a description of the business terms for the
Specification, RI and TCK that will apply when this JSR is final.


Section 3: Contributions

3.1 Please list any existing documents, specifications, or
implementations that describe the technology. Please include links to
the documents if they are publicly available.

JAX-RS 1.1 specification,

3.2 Explanation of how these items might be used as a starting point for
the work.

The JAX-RS 1.1 specification will be the starting point for this work.

Section 4: Additional Information

4.1 This section contains any additional information that the submitting
Member wishes to include in the JSR.