What are Best Tools/Libraries to make a REST Web Service?

Hi there

I am designing a Web Service in REST and I have selected Spring+Hibernate+Jackson Library to Design REST Web Service in Server Side.

I have few questions:
1)Can JSON response from Server Side can be Customized like can we add Some Flags in Response.Like some JSON object or JSON array in response.

2)I am also Utilizing this REST Web Service in android also.I have worked past using DefaultHttpClient to a Parse a JSON Response.My Question is what is Best way to Utilise REST Web Service in android.

It is using DefaultHttpClient or REST Template(I found by googleing...) or is there another way that work best in this seneraio.

Thanks

See http://android-developers.blogspot.de/2011/09/androids-http-clients.html for the Android team's perspective on which HTTP client to use.

Thanks I read this Post

http://android-developers.blogspot.de/2011/09/androids-http-clients.html

got my solutions