make Java HttpURLConnection support MKCOL PROFIND and other non-standard HTTP methods

    private static void setRequestMethod(HttpURLConnection conn, String method) throws Throwable {
        try {
            conn.setRequestMethod(method);
        } catch (ProtocolException e) {
            Class<?> c = conn.getClass();
            Field methodField = null;
            Field delegateField = null;
            try {
                delegateField = c.getDeclaredField("delegate");
            } catch (NoSuchFieldException nsfe) {

            }
            while (c != null && methodField == null) {
                try {
                    methodField = c.getDeclaredField("method");
                } catch (NoSuchFieldException nsfe) {

                }
                if (methodField == null) {
                    c = c.getSuperclass();
                }
            }
            if (methodField != null) {
                methodField.setAccessible(true);
                methodField.set(conn, method);
            }

            if (delegateField != null) {
                delegateField.setAccessible(true);
                HttpURLConnection delegate = (HttpURLConnection) delegateField.get(conn);
                setRequestMethod(delegate, method);
            }
        }
    }