Consume C# REST service with Java client

Question

I have following C# REST service definition

[OperationContract]
[WebInvoke(Method = "POST", UriTemplate = "books/{isbn}")]
void CreateBook(string isbn, Book book);

I want to consume this service from a Java client.

    String detail = "<Book><Autor>" + autor + "</Autor><ISBN>" + isbn + "</ISBN><Jahr>" + jahr + "</Jahr><Titel>" + titel + "</Titel></Book>";
    URL urlP = new URL("http://localhost:18015/BookRestService.svc/books/" + isbn);
    HttpURLConnection connectionP = (HttpURLConnection) urlP.openConnection();
    connectionP.setReadTimeout(15*1000);
    connectionP.setConnectTimeout(15*1000);
    connectionP.setRequestMethod("POST");
    connectionP.setDoOutput(true);
    connectionP.setRequestProperty("Content-Type", "application/xml"); 
    connectionP.setRequestProperty("Content-Length", Integer.toString( detail.length() )); 
    OutputStream os = connectionP.getOutputStream();
    PrintWriter pw = new PrintWriter(new OutputStreamWriter(os));
    pw.println(detail);
    pw.flush();
    pw.close();
    int retc = connectionP.getResponseCode();
    connectionP.disconnect();

The service returns 400 to my Java client. The same service works fine when called from a C# client.

Answer 1

I think that way you write to the stream may be the reason, try this:

connectionP.setDoOutput(true);
DataOutputStream out = new DataOutputStream(connectionP.getOutputStream());
out.writeBytes(detail);
out.flush();
out.close();

Answer 2

In your server code you use UriTemplate = "books/{isbn} as URI template, but your client code specifies the URI as "http://localhost:18015/BookRestService.svc/booksplain/" + isbn .

Maybe you only need to change the URI in Java code to reflect the server URI, for example "books" instead of "booksplain" "http://localhost:18015/BookRestService.svc/books/" + isbn .

Also, if you are interested in making your code cleaner and more concise, consider using Spring RestTemplate for making REST API calls.