java.net.malformedurlexception protocol not found android

Question

i am trying to reed an Rss XML From the Http , i used this tow mathode :

public String getXMLfromUrl(String url){
    String xml = null;
    try{
        DefaultHttpClient httpclient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);

        HttpResponse httpResponse = httpclient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        xml = EntityUtils.toString(httpEntity);
    }catch(Exception e){
        Log.e(" getXMLfromUrl : "," ",e);
    }
    return xml;
} 


public Document getDomElement(String xml){
    Document doc = null;
    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
    try{
        DocumentBuilder db = dbf.newDocumentBuilder();

        InputSource is = new InputSource();
            is.setCharacterStream(new StringReader(xml));
            doc = db.parse(xml);
            doc.getDocumentElement().normalize();
    }catch(Exception e){
        Log.e(" getDomElement : "," ",e);
    }
    return doc;
}

but i have a problem the first mathod dosn't return all the XML String , so the String not a will XML Format , i think my XML Stream is too long or cose i contain /n or may but cose contain Arabic characters , so the second Mathod throw java.net.malformedurlexception protocol not found android , or that what i think ....

pleas help me