getelementsbytagname returning zero

Question

I am using the following code to read a file .xml

    try {

        File fXmlFile = new File("C:\\res\\teste.xml"); // C:/.../teste.xml

        DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = dbFactory.newDocumentBuilder();
        Document doc = builder.parse(fXmlFile);

        //doc.getDocumentElement().normalize();

        NodeList nodeList = doc.getElementsByTagName("soapenv:Envelope");
        System.out.println(nodeList.getLength());
        for (int i = 0; i < nodeList.getLength(); i++) {
            Node mNode = nodeList.item(i);
            System.out.println("jjj2");
            if (mNode.getNodeType() == Node.ELEMENT_NODE) {
                Element mElement = (Element) mNode;
                String anoLido = "AnoSP: " + mElement.getElementsByTagName("apis:AnoSP").item(0).getTextContent();
                System.out.println("AnoSP: " + mElement.getElementsByTagName("apis:AnoSP").item(0).getTextContent());
                System.out.println("NumeroSP: " + mElement.getElementsByTagName("apis:NumeroSP").item(0).getTextContent());

            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    String anoLido = null;

    return null;

But the return of System.out.println(nodeList.getLength()); is coming as 0 even with file .xml containing the tags

XML file:

     <soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:tem="http://tempuri.org/" xmlns:apis="http://schemas.datacontract.org/2004/07/Integracao.Modelo.Chamada">
           <soapenv:Body>
            <tem:CancelaSP>
               <!--Optional:-->
               <tem:token>386922849949</tem:token>
               <!--Optional:-->
               <tem:cancelaSPIntegracao>
                  <!--Optional:-->
                  <apis:AnoSP>2016</apis:AnoSP>
                  <!--Optional:-->
                  <apis:NumeroSP>5656</apis:NumeroSP>
               </tem:cancelaSPIntegracao>
            </tem:CancelaSP>
         </soapenv:Body>
      </soapenv:Envelope>

Answer 1

Failed to inform the namespace respective to the node to be read.

NodeList nodeList = doc.getElementsByTagName("http://schemas.xmlsoap.org/soap/envelope/","Envelope");