Is it possible to configure JAX-RS method with variable number of URI parameters?

Question

is it possible to configure GET method to read variable number of URI parameters and interpret them either as variable argument (array) or collection? I know query parameters can be read as list/set but I can't go for them in my case.

E.g.:

@GET
@Produces("text/xml")
@Path("list/{taskId}")
public String getTaskCheckLists(@PathParam("taskId") int... taskId) {
    return Arrays.toString(taskId);
}

Thanks in advance

Answer 1

If I understand your question correctly, the @Path annotation can take a regular expression to specify a list of path components. For example, something like:

@GET
@Path("/list/{taskid:.+}")
public String getTaskCheckLists(@PathParam("taskid") List<PathSegment> taskIdList) {
    ......
}

There's a more extensive example here.

Answer 2

I am not submitting this as an answer as it is merely an edge case on the currently accepted answer which is what I've also used. In my case (Jersey 1.19) /list/{taskid:.+} would not work for the edge case of zero variable parameters. Changing the RegEx to /list/{taskid:.*} took care of that. See also this article (which seems to be applicable).

Moreover, upon changing the regexp to cardinality indicator to * (instead of +) I also had to deal programmatically with the case of empty strings as I would translate the List<PathSegment> into a List<String> (to pass it into my DB-access code).

The reason I am translating from PathSegment to String is that I didn't want a class from the javax.ws.rs.core package to pollute my Data Access Layer code.

Here's a complete example:

@Path("/listDirs/{dirs:.*}")
@GET
@Produces(MediaType.APPLICATION_JSON)
public Response listDirs(@PathParam("dirs") List<PathSegment> pathSegments) {
    List<String> dirs = new ArrayList<>();
    for (PathSegment pathSegment: pathSegments) {
        String path = pathSegment.getPath();
        if ((path!=null) && (!path.trim().equals("")))
            dirs.add(pathSegment.getPath());
    }
    List<String> valueFromDB = db.doSomeQuery(dirs);
    // construct JSON response object ...
}