Source Code

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package lession2;

/**
 *
 * @author Diep.Tran
 */
public class Student {
    String rollNo, fullname, gender, address;

    public Student() {
    }

    public Student(String rollNo, String fullname, String gender, String address) {
        this.rollNo = rollNo;
        this.fullname = fullname;
        this.gender = gender;
        this.address = address;
    }

    public String getRollNo() {
        return rollNo;
    }

    public void setRollNo(String rollNo) {
        this.rollNo = rollNo;
    }

    public String getFullname() {
        return fullname;
    }

    public void setFullname(String fullname) {
        this.fullname = fullname;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "Student{" + "rollNo=" + rollNo + ", fullname=" + fullname + ", gender=" + gender + ", address=" + address + '}';
    }
    
    public String getXMLString() {
        return "<student>\n" +
"		<rollNo>"+rollNo+"</rollNo>\n" +
"		<fullname>"+fullname+"</fullname>\n" +
"		<address>"+address+"</address>\n" +
"		<gender>"+gender+"</gender>\n" +
"	</student>";
    }
}

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package lession2;

import java.util.ArrayList;
import java.util.List;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

/**
 *
 * @author Diep.Tran
 */
public class StudentHandler extends DefaultHandler{
    List<Student> studentList = new ArrayList<>();
    Student currentStudent = null;
    
    boolean isRollNo = false, isFullname = false, isGender = false, isAddress = false;
    
    @Override
    public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
        if(qName.equalsIgnoreCase("student")) {
            currentStudent = new Student();
        } else if(qName.equalsIgnoreCase("rollNo")) {
            isRollNo = true;
        } else if(qName.equalsIgnoreCase("fullname")) {
            isFullname = true;
        } else if(qName.equalsIgnoreCase("gender")) {
            isGender = true;
        } else if(qName.equalsIgnoreCase("address")) {
            isAddress = true;
        }
    }

    @Override
    public void endElement(String uri, String localName, String qName) throws SAXException {
        if(qName.equalsIgnoreCase("student")) {
            studentList.add(currentStudent);
            currentStudent = null;
        } else if(qName.equalsIgnoreCase("rollNo")) {
            isRollNo = false;
        } else if(qName.equalsIgnoreCase("fullname")) {
            isFullname = false;
        } else if(qName.equalsIgnoreCase("gender")) {
            isGender = false;
        } else if(qName.equalsIgnoreCase("address")) {
            isAddress = false;
        }
    }

    @Override
    public void characters(char[] ch, int start, int length) throws SAXException {
        String value = new String(ch, start, length);
        
        if(isRollNo) {
            currentStudent.setRollNo(value);
        } else if(isFullname) {
            currentStudent.setFullname(value);
        } else if(isGender) {
            currentStudent.setGender(value);
        } else if(isAddress) {
            currentStudent.setAddress(value);
        }
    }

    public List<Student> getStudentList() {
        return studentList;
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<studentList>
<student>
		<rollNo>R001</rollNo>
		<fullname>TRAN VAN A</fullname>
		<address>HA NOI</address>
		<gender>Male</gender>
	</student><student>
		<rollNo>R002</rollNo>
		<fullname>TRAN VAN B</fullname>
		<address>NAM DINH</address>
		<gender>Male</gender>
	</student><student>
		<rollNo>R003</rollNo>
		<fullname>TRAN VAN B</fullname>
		<address>NAM DINH</address>
		<gender>Male</gender>
	</student><student>
		<rollNo>R004</rollNo>
		<fullname>TRAN VAN C</fullname>
		<address>NAM DINH</address>
		<gender>Male</gender>
	</student><student>
		<rollNo>R005</rollNo>
		<fullname>TRAN VAN E</fullname>
		<address>NAM DINH</address>
		<gender>Male</gender>
	</student><student>
		<rollNo>R006</rollNo>
		<fullname>Tran Van T</fullname>
		<address>OKOK</address>
		<gender>Male</gender>
	</student>
</studentList>

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package lession2;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JOptionPane;
import javax.swing.table.DefaultTableModel;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.SAXException;

/**
 *
 * @author Diep.Tran
 */
public class StudentFrame extends javax.swing.JFrame {
    DefaultTableModel tableModel;
    List<Student> studentList = new ArrayList<>();
    
    /**
     * Creates new form StudentFrame
     */
    public StudentFrame() {
        initComponents();
        
        tableModel = (DefaultTableModel) tblStudent.getModel();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jPanel1 = new javax.swing.JPanel();
        jLabel1 = new javax.swing.JLabel();
        txtRollNo = new javax.swing.JTextField();
        jLabel2 = new javax.swing.JLabel();
        txtFullName = new javax.swing.JTextField();
        jLabel3 = new javax.swing.JLabel();
        txtAddress = new javax.swing.JTextField();
        jLabel4 = new javax.swing.JLabel();
        cbGender = new javax.swing.JComboBox<>();
        btnSave = new javax.swing.JButton();
        btnExportXML = new javax.swing.JButton();
        btnImportXML = new javax.swing.JButton();
        jScrollPane1 = new javax.swing.JScrollPane();
        tblStudent = new javax.swing.JTable();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("Student Manager");

        jPanel1.setBorder(javax.swing.BorderFactory.createTitledBorder("Input Student's Detail Information"));

        jLabel1.setText("Roll No:");

        jLabel2.setText("Full Name:");

        jLabel3.setText("Gender:");

        jLabel4.setText("Address:");

        cbGender.setModel(new javax.swing.DefaultComboBoxModel<>(new String[] { "Male", "Female" }));

        btnSave.setText("Save");
        btnSave.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnSaveActionPerformed(evt);
            }
        });

        btnExportXML.setText("Export XML");
        btnExportXML.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnExportXMLActionPerformed(evt);
            }
        });

        btnImportXML.setText("Import XML");
        btnImportXML.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnImportXMLActionPerformed(evt);
            }
        });

        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addGap(21, 21, 21)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jLabel1)
                    .addComponent(jLabel4)
                    .addComponent(jLabel3)
                    .addComponent(jLabel2))
                .addGap(28, 28, 28)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addComponent(txtRollNo, javax.swing.GroupLayout.PREFERRED_SIZE, 253, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                        .addComponent(btnSave, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addComponent(txtAddress, javax.swing.GroupLayout.PREFERRED_SIZE, 253, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(0, 0, Short.MAX_VALUE))
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addComponent(cbGender, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(165, 165, 165)
                        .addComponent(btnExportXML, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addComponent(txtFullName, javax.swing.GroupLayout.PREFERRED_SIZE, 253, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(12, 12, 12)
                        .addComponent(btnImportXML, javax.swing.GroupLayout.DEFAULT_SIZE, 125, Short.MAX_VALUE)))
                .addContainerGap())
        );
        jPanel1Layout.setVerticalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addGap(15, 15, 15)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel1)
                    .addComponent(txtRollNo, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnSave))
                .addGap(18, 18, 18)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel2)
                    .addComponent(txtFullName, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnImportXML))
                .addGap(18, 18, 18)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel3)
                    .addComponent(cbGender, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnExportXML))
                .addGap(18, 18, 18)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel4)
                    .addComponent(txtAddress, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addContainerGap(30, Short.MAX_VALUE))
        );

        tblStudent.setModel(new javax.swing.table.DefaultTableModel(
            new Object [][] {

            },
            new String [] {
                "Roll No", "Full Name", "Gender", "Address"
            }
        ) {
            boolean[] canEdit = new boolean [] {
                false, false, true, false
            };

            public boolean isCellEditable(int rowIndex, int columnIndex) {
                return canEdit [columnIndex];
            }
        });
        jScrollPane1.setViewportView(tblStudent);

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(jScrollPane1))
                .addContainerGap())
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 146, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );

        pack();
    }// </editor-fold>                        

    private void btnSaveActionPerformed(java.awt.event.ActionEvent evt) {                                        
        // TODO add your handling code here:
        String rollNo = txtRollNo.getText();
        String fullname = txtFullName.getText();
        String gender = cbGender.getSelectedItem().toString();
        String address = txtAddress.getText();
        
        if(rollNo.isEmpty() || fullname.isEmpty()) {
            JOptionPane.showMessageDialog(rootPane, "RollNo is empty || fullname is empty?");
            return;
        }
        
        for (Student student : studentList) {
            if(student.getRollNo().equalsIgnoreCase(rollNo)) {
                JOptionPane.showMessageDialog(rootPane, "RollNo existed!!!");
                return;
            }
        }
        
        Student std = new Student(rollNo, fullname, gender, address);
        studentList.add(std);
        
        tableModel.addRow(new Object[] {rollNo, fullname, gender, address});
    }                                       

    private void btnImportXMLActionPerformed(java.awt.event.ActionEvent evt) {                                             
        FileInputStream fis = null;
        try {
            // TODO add your handling code here:
            fis = new FileInputStream("student.xml");
            SAXParserFactory factory = SAXParserFactory.newInstance();
            SAXParser parser = factory.newSAXParser();
            
            StudentHandler handler = new StudentHandler();
            
            parser.parse(fis, handler);
            
            studentList = handler.getStudentList();
            
            tableModel.setRowCount(0);
            
            for (Student student : studentList) {
                tableModel.addRow(new Object[] {
                    student.getRollNo(), student.getFullname(),
                    student.getGender(), student.getAddress()
                });
            }
        } catch (FileNotFoundException ex) {
            Logger.getLogger(StudentFrame.class.getName()).log(Level.SEVERE, null, ex);
        } catch (ParserConfigurationException ex) {
            Logger.getLogger(StudentFrame.class.getName()).log(Level.SEVERE, null, ex);
        } catch (SAXException ex) {
            Logger.getLogger(StudentFrame.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(StudentFrame.class.getName()).log(Level.SEVERE, null, ex);
        } finally {
            try {
                fis.close();
            } catch (IOException ex) {
                Logger.getLogger(StudentFrame.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
        
        JOptionPane.showMessageDialog(rootPane, "Import success!!!");
    }                                            

    private void btnExportXMLActionPerformed(java.awt.event.ActionEvent evt) {                                             
        // TODO add your handling code here:
        StringBuilder builder = new StringBuilder();
        for (Student student : studentList) {
            builder.append(student.getXMLString());
        }
        
        String body = builder.toString();
        String xml = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
                    "<studentList>\n" +
                                    body+
                    "\n</studentList>";
        //save into file student.xml
        FileOutputStream fos = null;
        
        try {
            fos = new FileOutputStream("student.xml");
            
            byte[] data = xml.getBytes();
            
            fos.write(data);
        } catch(Exception e) {
            e.printStackTrace();
        } finally {
            if(fos != null) {
                try {
                    fos.close();
                } catch (IOException ex) {
                    Logger.getLogger(StudentFrame.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        }
        
        JOptionPane.showMessageDialog(rootPane, "Save success!!!");
    }                                            

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(StudentFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(StudentFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(StudentFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(StudentFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new StudentFrame().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JButton btnExportXML;
    private javax.swing.JButton btnImportXML;
    private javax.swing.JButton btnSave;
    private javax.swing.JComboBox<String> cbGender;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel3;
    private javax.swing.JLabel jLabel4;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JTable tblStudent;
    private javax.swing.JTextField txtAddress;
    private javax.swing.JTextField txtFullName;
    private javax.swing.JTextField txtRollNo;
    // End of variables declaration                   
}