Obtaining information about URIs using UriInfo objects

Using Java API for RESTful Web Services (JAX-RS), you can use the UriInfo object to access request headers. The UriInfo object provides methods to enable you to find or build URI information of a request.

• If a resource method signature can be modified, add the @javax.ws.rs.core.Context javax.ws.rs.core.UriInfo parameter to the method. When the resource method is invoked, the JAX-RS runtime environment passes an object that implements the UriInfo object; for example:

  @Path("/contextexample")
  public class RootResource {
      @GET
      public String getResource(@Context UriInfo uriInfo) {
          /* This calls a method on the uriInfo object. */
          return "The client used this URI to reach this resource method: " + uriinfo.getAbsolutePath().toASCIIString();
      }
  }

• If a resource method signature cannot be modified and the class is a root resource, add the @javax.ws.rs.core.Context javax.ws.rs.core.HttpHeaders field. When the resource is instantiated for a request, an object that implements UriInfo is injected; for example:

  @Path("/contextexample")
  public class RootResource {
  
      @Context
      UriInfo uriInfo;
  
     @GET
      public String getResource() {
          /* This calls a method on the uriInfo object. */
          return "The client used this URI to reach this resource method: " + uriinfo.getAbsolutePath().toASCIIString();
      }
  }

import   javax.ws.rs.GET; 
import   javax.ws.rs.Path; 
import   javax.ws.rs.Produces; 
import   javax.ws.rs.core.Context; 
import   javax.ws.rs.core.UriInfo; 
import   javax.ws.rs.core.MediaType; 
  
@Path ( "/books" ) 
public   class  BookListResource   { 
  
     @GET
     @Produces(MediaType.TEXT_PLAIN)
     public   String  getBookList()   {
        return "a list of books";
      }
} 

import   java.util.List; 
import   java.util.Locale; 
  
import   javax.ws.rs.GET; 
import   javax.ws.rs.Path; 
import   javax.ws.rs.Produces; 
import   javax.ws.rs.core.Context; 
import   javax.ws.rs.core.UriInfo; 
import   javax.ws.rs.core.MediaType; 
  
@Path ( "/allitems" ) 
public   class  AllItemsListResource   { 
  
     @GET
     @Produces(MediaType.TEXT_PLAIN)
     public   String   getLocationOfAllItems(@Context UriInfo uriInfo)   { 
        URI bookListURI = uriInfo.getBaseUriBuilder().path(BookListResource.class).build();
        return Response.ok("The URI to the book list is: " + bookListURI..toASCIIString()).build();
      }
}