Model

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.io.File;
import java.text.SimpleDateFormat;
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.List;

public class PatientsModel {

    private String patientSurname;
    private String town;

    private String filePath = "AllPatient.xml";
    private List<PatientsModel> modelArray = new ArrayList<PatientsModel>();
    private DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy");

    public String getPatientSurname(){
        return this.patientSurname;
    }
    public void setPatientSurname(String newPatientSurname){
        this.patientSurname = newPatientSurname;
    }

    public String getTown(){
        return this.town;
    }

    public void setTown(String newTown){
        this.town = newTown;
    }

    public List<PatientsModel> getModelArray(){
        return modelArray;
    }


    private void addNewElArr(){

        PatientsModel newModel = new PatientsModel();

        newModel.setPatientSurname(patientSurname);
        newModel.setTown(town);

        modelArray.add(newModel);
    }

    public void readXMLbySAX() { //String strPatientFio,String strAdress) {
        try {
            modelArray.clear();
            SAXParserFactory factory = SAXParserFactory.newInstance();
            SAXParser saxParser = factory.newSAXParser();

            DefaultHandler handler = new DefaultHandler() {

                boolean bPatientSurname = false;
                boolean bTown = false;


                public void startElement(String uri, String localName, String qPatientTag,
                                         Attributes attributes) throws SAXException {

                    if (qPatientTag.equalsIgnoreCase("patientSurname")) {
                        bPatientSurname = true;
                    }

                    if (qPatientTag.equalsIgnoreCase("town")) {
                        bTown = true;
                    }
                }

                public void endElement(String uri, String localName,
                                       String qPatientTag) throws SAXException {

                    if (qPatientTag.equalsIgnoreCase("patient")) {
                        System.out.println("end of tag :");// + maxPatient);
                    }
                }

                public void characters(char ch[], int start, int length) throws SAXException {

                    if(bPatientSurname){
                        System.out.println("PatientSurname : " + new String(ch, start, length));
                        bPatientSurname = false;
                        setPatientSurname(new String(ch, start, length));
                        System.out.println("Текущая фамилия :" + patientSurname);
                    }

                    if (bTown) {
                        System.out.println("town : " + new String(ch, start, length));
                        bTown = false;
                        setTown(new String(ch, start, length));
                        System.out.println("Текущий город :" + town);
                        addNewElArr();
                    }
                }
            };

            saxParser.parse(filePath, handler);

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

    public void writeXML(String strPatientSurname,String strTown) {
        //DOM
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder;
        try {
            builder = factory.newDocumentBuilder();
            Document document;
            File file = new File(filePath);
            if(file.length() == 0){
                document = factory.newDocumentBuilder().newDocument();
                Element root = document.createElement("root");
                document.appendChild(root);
            }
            else {
                document = builder.parse(filePath);
            }
            System.out.println("ХОБА1");
            document.getDocumentElement().normalize();
            SimpleDateFormat simpleDateFormat = new SimpleDateFormat("dd/MM/YYYY");
            //String birthStr = (dateOfBirth).format(formatter);
            //String receiptStr = localDateOfReceipt.format(formatter);

            //addNewTag(document, strPatientSurname,strPatientName,strPatientPatronym, strTown,strStreet,strHouse,
            //        strFlat, strDoctorSurname,strDoctorName,strDoctorPatronym, strConclusion, birthStr, receiptStr);
            addNewTag(document,strPatientSurname,strTown);
            document.getDocumentElement().normalize();
            TransformerFactory transformerFactory = TransformerFactory.newInstance();
            Transformer transformer = transformerFactory.newTransformer();
            DOMSource source = new DOMSource(document);
            StreamResult result = new StreamResult(new File(filePath));
            transformer.setOutputProperty(OutputKeys.INDENT, "yes");
            transformer.transform(source, result);


        }catch (SAXParseException exception){
            System.out.println("ERRROR");
        }
        catch (Exception exc) {
            exc.printStackTrace();
        }
    }

    //private void addNewTag(Document doc, String strPatientSurname,String strPatientName,String strPatientPatronym,
    //                       String strTown,String strStreet,String strHouse,String strFlat,
    //                       String strDoctorSurname,String strDoctorName,String strDoctorPatronym,
    //                       String newConcl, String Birthday, String Receiptday) {

    private void addNewTag(Document doc,String strPatientSurname,String strTown){
        NodeList patients = doc.getElementsByTagName("root");
        Element lang = null;

        int i = patients.getLength();
        lang = (Element) patients.item(i - 1);

        Element patient = doc.createElement("patient");

        Element patientSurname = doc.createElement("patientSurname");
        //Element patientName = doc.createElement("patientName");
        //Element patientPatronym = doc.createElement("patientPatronym");

        Element town = doc.createElement("town");
       // Element street = doc.createElement("street");
        /*Element house = doc.createElement("house");
        Element flat = doc.createElement("flat");

        Element doctorSurname = doc.createElement("doctorSurname");
        Element doctorName = doc.createElement("doctorName");
        Element doctorPatronym = doc.createElement("doctorPatronym");

        Element conclusion = doc.createElement("conclusion");
        Element dateOfBirth = doc.createElement("dateOfBirth");
        Element dateOfReceipt = doc.createElement("dateOfReceipt");
        */

        patientSurname.appendChild(doc.createTextNode(strPatientSurname));
       // patientName.appendChild(doc.createTextNode(strPatientName));
        //patientPatronym.appendChild(doc.createTextNode(strPatientPatronym));
        town.appendChild(doc.createTextNode(strTown));
        /*street.appendChild(doc.createTextNode(strStreet));
        house.appendChild(doc.createTextNode(strHouse));
        flat.appendChild(doc.createTextNode(strFlat));

        doctorSurname.appendChild(doc.createTextNode(strDoctorSurname));
        doctorName.appendChild(doc.createTextNode(strDoctorName));
        doctorPatronym.appendChild(doc.createTextNode(strDoctorPatronym));

        conclusion.appendChild(doc.createTextNode(newConcl));
        dateOfBirth.appendChild(doc.createTextNode(Birthday));//String to LocalDate
        dateOfReceipt.appendChild(doc.createTextNode(Receiptday));
        */

        patient.appendChild((patientSurname));
        //patient.appendChild((patientName));
        //patient.appendChild((patientPatronym));

        patient.appendChild((town));
        /*patient.appendChild((street));
        patient.appendChild((house));
        patient.appendChild((flat));

        patient.appendChild(doctorSurname);
        patient.appendChild(doctorName);
        patient.appendChild(doctorPatronym);
        patient.appendChild(conclusion);
        patient.appendChild(dateOfBirth);
        patient.appendChild(dateOfReceipt);
        */

        lang.appendChild(patient);
    }

    public void delTag(int willDel) {
        try {
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder;
            builder = factory.newDocumentBuilder();
            Document document = builder.parse(filePath);
            Element element = (Element) document.getElementsByTagName("patient").item(willDel);

            Node parent = element.getParentNode();
            parent.removeChild(element);
            parent.normalize();

            TransformerFactory transformerFactory = TransformerFactory.newInstance();
            Transformer transformer = transformerFactory.newTransformer();
            DOMSource source = new DOMSource(document);
            StreamResult result = new StreamResult(new File(filePath));
            transformer.setOutputProperty(OutputKeys.INDENT, "yes");
            transformer.transform(source, result);


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


}