geoserver - Using Geotools or GeoserverManager to add a layer using just an URL

Lets say I have just an URL to a Layer in OpenLayers format:

http://www.geoservicos.ibge.gov.br/geoserver/CREN/wms?service=WMS&version=1.1.0&request=GetMap&layers=HidrogeologiaRegiaoNE

Is it possible to create a Layer in my Geoserver pointing to this external layer?

1) Using my Geoserver I've tried to use Web Feature Server (NG) but I don't want to list all layers before add it (GetCapabilities).

2) I need to do it using geotools. Again, GetCapabilities will be time spending because I already know the layer I want to add.

I can use Geotools or Geoserver Manager (REST API). I've searched everywhere for examples to add (publish) a WMS layer from a external geoserver layer but found nothing.

In other words, how can I do this using GeoserverManager API?
http://geoserver.geo-solutions.it/edu/en/adding_data/add_wfscascade.html

Answer

Found it!

Following this post I've discovered the data to send to the REST API: Adding an external WMS service using REST service with Geoserver

POST /rest/workspaces//wmsstores


   wms
   http://somehost/wms?

   sf

Now, I need to know HOW. Found this: http://boundlessgeo.com/2012/10/adding-layers-to-geoserver-using-the-rest-api/ with a lot of CURL examples to talk to the Geoserver REST API. None of them is what I need.

Now I just put the two parts together: The correct data with correct protocol, something like:

    curl -u admin:geoserver -v -XPOST -H 'Content-type:text/xml' -d '
       wmshttp://somehost/wms?
sf' 
http://mygeoserver/rest/workspaces/target_workspace/wmsstores

But I need it in Java...

The caller:

    try {

        String workspace = "test";
        String myServer = "http://10.5.115.22/geoserver/rest/workspaces/"+workspace+"/wmsstores";

        String urlToAdd = "http://www.geoservicos.ibge.gov.br/geoserver/wms?";
        String wsToAdd = "CREN";


        StringBuilder postData = new StringBuilder();
        postData.append("");
        postData.append("wms");
        postData.append("" + urlToAdd + "");
        postData.append("" + wsToAdd + "");
        postData.append("");

        WebClient wc = new WebClient();
        wc.doPostStream(myServer, postData.toString() );



    } catch ( Exception e ) {
        e.printStackTrace();
    } 

... and the connection (CURL Java like):

public void doPostStream( String url, String content ) throws Exception {
    String encodedAuth = new String( Base64.encodeBase64( "admin:geoserver".getBytes() ) );
    HttpURLConnection con = (HttpURLConnection) new URL( url ).openConnection();
    con.setRequestMethod("POST");

    con.setRequestProperty("Authorization", "Basic " + encodedAuth );
    con.setRequestProperty("User-Agent", USER_AGENT);
    con.setRequestProperty("Content-type", "text/xml");

    con.setDoOutput(true);
    con.getOutputStream().write( content.getBytes("UTF-8") );

    InputStream inputStream = con.getInputStream();
    StringWriter writer = new StringWriter();
    IOUtils.copy(inputStream, writer, "UTF-8");

    String theString = writer.toString();
    System.out.println( theString );    

    con.disconnect();
    inputStream.close();

}

Now, my WMS Store was created! But instead the type of the store I have an interrogation:

I think it is because the URL http://www.geoservicos.ibge.gov.br/geoserver/wms? is not in proper format to this kind of store.

Investigating...

EDIT: The answer is in the same post, @tareq comment:

You can add WMS into wmsStore-tag so in the datasources overview in geoserver the type of this datasource gets specified instead of default "?"