JAX-RS is awesome to say the least and one of my favorites! Why?
- Feature rich
- Intuitive (hence the learning curve is not as steep)
- Easy-to-use and develop with
- Has great RIs – Jersey, RestEasy etc
There are enough JAX-RS fans out there who can add to this! đ
JAX-RS 2.0 is the latest version of the JSR 311 specification and it was released along with Java EE 7.
Life without @BeanParam
Before JAX-RS 2.0, in order to pass/inject information from an HTTP request into JAX-RS resource implementation methods, one could
1. Include multiple method arguments annotated with @FormParam, @PathParam, @QueryParam etc
2. Or, have a model class backed by JAXB/JSON or a custom MessageBodyReader implementation for JAX-RS Provider to be able to unmarshall the HTTP message body to a Java object – read more about this in one of my previous posts
This means that something like a HTML5 based client would need to extract the FORM input, convert it into JSON or XML payload and then POST it over the wire.
Simplification in JAX-RS 2.0
This process has been simplified by introduction of the @BeanParam annotation. It helps inject custom value/domain/model objects into fields or method parameters of JAX-RS resource classes.
In case you want to refer to the code (pretty simple) or download the example/run it yourself, here is the GitHub link
All we need to do is, annotate the fields of the model (POJO) class with the injection annotations that already exist i.e. @PathParam, @QueryParam, @HeaderParam, @MatrixParam etc – basically any of the @xxxParam metadata types and
Make sure that we include the @BeanParam annotation while injecting a reference variable of this POJO (only on METHOD, PARAMETER or FIELD).
JAX-RS provider automatically constructs and injects an instance of your domain object which you can now use within your methods.
Just fill in the form information and POST it !
That’s it. . . Short and Sweet đ
Keep Coding !
Head in the clouds 
Buddy, you just copy and pasted this tutorial from this link : http://java.dzone.com/articles/new-jax-rs-20-%E2%80%93-beanparam
Please give some credit to original author.
Peace.
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Hi Avinash – it just happens to be a coincidence that the author of this post and the one you pointed ( http://java.dzone.com/articles/new-jax-rs-20-%E2%80%93-beanparam) are the same.
Giving credit to self for a republished blog of mine on a different site ?? Not my style đ
Best Regards always! Thanks for visiting…
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Can you please explain the advantage of using BeanParam when compared to using JAXB annotated POJO ? When BeanParam is used, there is no marshalling/unmarshalling happening in background?
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@BeanParam and JAXB support (in JAX-RS) are two different topics altogether. The former makes it easy to inject data from various sources (headers, cookies etc.) by allowing you to represent them as a a single POJO (bean), rather than injecting them individually. To answer your question, there is no marshalling/unmarhshalling happening here. JAX-RS runtime just injects the POJO. Since JAXB support is provided by JAX-RS implementations by default, the serialization/deserialzation is taken care of by the runtime/framework itself.
Hope this helped
Cheers!
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How we pass this it at client side i mean URL
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Pallavi
It depends on what you’re trying to inject i.e. headers, cookies, query parameters etc. All these need to passed from the client in the standard ‘HTTP’ style.
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Hi Abhishek,
Can BeanParam support JSON payload? If not then is there any other annotation which can wrap all the xxxParam and post request’s JSON payload in a single object?
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JSON payload support is available in JAX-RS 2.0 using the JSON-P API
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