Why query params are not reaching the interface?-CodePudding

I'am trying to send a request to a REST interface implemented with javax.ws.rs and give it some query params, but the query params do not reach the interface.

The sending side is implemented as folowing:

WebTarget target = webTarget.path("test").path("Testuser");
target.queryParam("a","a");

System.out.println(target.getUri());
Response response = target.request().get();

The interface:

@GET
@Path("test/{username}")
public void test(
        @PathParam("username") String username,
        @QueryParam("a") String a) {
    System.out.println("TEST here!");
    System.out.println("username: "   username);
    System.out.println("a: "   a);
}

The output on the sender side is the plain URL without any query parameter.

The output on the interface side is

TEST here!
username: Testuser
a: null

I'am not able to see, where my error is, and why the a is not recived in the interface.

CodePudding user response：

You're ignoring the result of the queryParam method. The method doesn't modify the existing instance - it returns a new one, just like path does. From the docs:

Create a new WebTarget instance by configuring a query parameter on the URI of the current target instance.

Just change your code to:

WebTarget target = webTarget.path("test").path("Testuser").queryParam("a", "a");