Get HTTP header in JAX-RS

In this tutorial, we show you two ways to get HTTP request header in JAX-RS :

1. Inject directly with @HeaderParam
2. Pragmatically via @Context

Note
Refer to this wiki page for list of the HTTP header fields.

1. @HeaderParam Example

In this example, it gets the browser “user-agent” from request header.

import javax.ws.rs.GET;
import javax.ws.rs.HeaderParam;
import javax.ws.rs.Path;
import javax.ws.rs.core.Response;

@Path("/users")
public class UserService {

	@GET
	@Path("/get")
	public Response addUser(@HeaderParam("user-agent") String userAgent) {

		return Response.status(200)
			.entity("addUser is called, userAgent : " + userAgent)
			.build();

	}

}

Access via URI pattern “/users/get“, with FireFox, see following result :

addUser is called, userAgent : Mozilla/5.0 (Windows NT 6.1; rv:5.0) Gecko/20100101 Firefox/5.0

2. @Context Example

Alternatively, you can use @Context to get “javax.ws.rs.core.HttpHeaders” directly, see equivalent version to get browser “user-agent“.

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.HttpHeaders;
import javax.ws.rs.core.Response;

@Path("/users")
public class UserService {

	@GET
	@Path("/get")
	public Response addUser(@Context HttpHeaders headers) {

		String userAgent = headers.getRequestHeader("user-agent").get(0);
		
		return Response.status(200)
			.entity("addUser is called, userAgent : " + userAgent)
			.build();

	}

}

Access via URI pattern “/users/get“, with Google Chrome, see following result :

addUser is called, userAgent : Mozilla/5.0 (Windows NT 6.1) AppleWebKit/534.30 
	(KHTML, like Gecko) Chrome/12.0.742.112 Safari/534.30

List all request headers
You can list all available HTTP request headers via following code :

for(String header : headers.getRequestHeaders().keySet()){
	System.out.println(header);
}

Download Source Code

$ git clone https://github.com/favtuts/java-jax-rs-tutorials.git
$ cd jax-rs-httpheaders-example

References

1. JAX-RS HttpHeaders JavaDoc
2. JAX-RS @HeaderParam JavaDoc
3. Full list of HTTP header fields