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POCurrent date wont update
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copied!<p>I have 2 buttons one to log in and the other to log out. I would like both of them to show different times but for some reason unknown to me they do not. and when all the info is saved to a file it says null where there's no information. If there is a way to change that it would be greatly appreciated.</p> <pre><code>import java.awt.BorderLayout; import java.awt.GridBagConstraints; import java.awt.GridBagLayout; import java.awt.GridLayout; import java.awt.Insets; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; import java.io.FileNotFoundException; import java.io.PrintWriter; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Date; import javax.swing.*; import javax.swing.event.ListSelectionEvent; import javax.swing.event.ListSelectionListener; import javax.swing.text.AttributeSet; import javax.swing.text.BadLocationException; import javax.swing.text.PlainDocument; public class MainGUI extends JFrame { DateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss"); Date date = new Date(); String[] columnNames = {"ID", "NAME", "COURSE", "Professor", "Reason for Tutor", "Login Time", "Logout Time"}; Object[][] data = new Object[25][7]; // table JTable table = new JTable(data, columnNames) { @Override public boolean isCellEditable(int row, int column) { return false; } }; JFrame frame, frame1; JPanel buttonPanel, buttonPanel2, tablePanel, addPanel, editPanel; JLabel labelID, labelName, labelCourse, labelProfessor, labelHelp, labelDate, labelDate2; JTextField txtID, txtName, txtCourse, txtProfessor, txtHelp, txtDate, txtDate2; JButton btnAdd, btnEdit, btnDelete, btnSort, btnSave, btnAddInput, btnCancel; int keyCode, rowIndex, rowNumber, noOfStudents; MainGUI.ButtonHandler bh = new MainGUI.ButtonHandler(); public MainGUI() { table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION); table.getSelectionModel().addListSelectionListener(new MainGUI.RowListener()); table.getColumnModel().getColumn(1).setPreferredWidth(150); table.getColumnModel().getColumn(3).setPreferredWidth(100); table.getColumnModel().getColumn(4).setPreferredWidth(200); table.getColumnModel().getColumn(5).setPreferredWidth(150); table.getColumnModel().getColumn(6).setPreferredWidth(150); table.getTableHeader().setResizingAllowed(false); table.getTableHeader().setReorderingAllowed(false); JScrollPane scrollPane = new JScrollPane(table); btnAdd = new JButton("Login"); btnAdd.addActionListener(bh); btnEdit = new JButton("EDIT"); btnEdit.addActionListener(bh); btnEdit.setEnabled(false); btnDelete = new JButton("DELETE"); btnDelete.addActionListener(bh); btnDelete.setEnabled(false); btnSort = new JButton("Logout"); btnSort.addActionListener(bh); btnSave = new JButton("SAVE"); btnSave.addActionListener(bh); btnSave.setActionCommand("Save"); btnAddInput = new JButton("Login"); btnAddInput.addActionListener(bh); btnAddInput.setActionCommand("AddInput"); btnCancel = new JButton("Cancel"); btnCancel.addActionListener(bh); labelID = new JLabel("ID"); labelName = new JLabel("NAME"); labelCourse = new JLabel("Course"); labelProfessor = new JLabel("Professor"); labelHelp = new JLabel("Reason for Tutoring"); labelDate = new JLabel("Login"); labelDate2 = new JLabel("Logout"); txtID = new JTextField(20); txtName = new JTextField(20); txtCourse = new JTextField(20); txtProfessor = new JTextField(20); txtHelp = new JTextField(20); txtDate = new JTextField(20); txtDate2 = new JTextField(20); txtID.setDocument(new MainGUI.JTextFieldLimit(15)); txtID.addKeyListener(keyListener); tablePanel = new JPanel(); tablePanel.setLayout(new BoxLayout(tablePanel, BoxLayout.PAGE_AXIS)); tablePanel.setBorder(BorderFactory.createEmptyBorder(10, 2, 0, 10)); tablePanel.add(table.getTableHeader()); tablePanel.add(table); buttonPanel = new JPanel(); buttonPanel.setLayout(new GridBagLayout()); GridBagConstraints c = new GridBagConstraints(); c.gridx = 0; c.gridy = 0; c.ipady = 20; c.insets = new Insets(10, 10, 10, 10); c.fill = GridBagConstraints.HORIZONTAL; buttonPanel.add(btnAdd, c); c.gridx = 0; c.gridy = 1; c.fill = GridBagConstraints.HORIZONTAL; c.ipady = 20; c.insets = new Insets(10, 10, 10, 10); buttonPanel.add(btnEdit, c); c.gridx = 0; c.gridy = 2; c.fill = GridBagConstraints.HORIZONTAL; c.ipady = 20; c.insets = new Insets(10, 10, 10, 10); buttonPanel.add(btnDelete, c); c.gridx = 0; c.gridy = 3; c.ipady = 20; c.insets = new Insets(10, 10, 10, 10); c.fill = GridBagConstraints.HORIZONTAL; buttonPanel.add(btnSort, c); c.gridx = 0; c.gridy = 4; c.ipady = 20; c.insets = new Insets(10, 10, 10, 10); c.fill = GridBagConstraints.HORIZONTAL; buttonPanel.add(btnSave, c); frame = new JFrame("Tutoring Database"); frame.setVisible(true); frame.setResizable(false); frame.setDefaultCloseOperation(EXIT_ON_CLOSE); frame.add(tablePanel, BorderLayout.CENTER); frame.add(buttonPanel, BorderLayout.EAST); frame.pack(); addPanel = new JPanel(); addPanel.setLayout(new GridBagLayout()); c.insets = new Insets(1, 0, 1, 1); c.gridx = 0; c.gridy = 0; addPanel.add(labelID, c); c.gridy = 1; addPanel.add(labelName, c); c.gridy = 2; addPanel.add(labelCourse, c); c.gridy = 3; addPanel.add(labelProfessor, c); c.gridy = 4; addPanel.add(labelHelp, c); c.gridy = 5; addPanel.add(labelDate, c); c.gridy = 6; addPanel.add(labelDate2, c); // text fields c.gridx = 1; c.gridy = 0; c.ipady = 1; addPanel.add(txtID, c); c.gridy = 1; c.ipady = 1; addPanel.add(txtName, c); c.gridy = 2; c.ipady = 1; addPanel.add(txtCourse, c); c.gridy = 3; c.ipady = 1; addPanel.add(txtProfessor, c); c.gridy = 4; c.ipady = 1; addPanel.add(txtHelp, c); c.gridy = 5; c.ipady = 1; addPanel.add(txtDate, c); c.gridy = 5; c.ipady = 1; addPanel.add(txtDate2, c); buttonPanel2 = new JPanel(); buttonPanel2.setLayout(new GridLayout(1, 1)); buttonPanel2.add(btnAddInput); buttonPanel2.add(btnCancel); frame1 = new JFrame("Student Database"); frame1.setVisible(false); frame1.setResizable(false); frame1.setDefaultCloseOperation(HIDE_ON_CLOSE); frame1.add(addPanel, BorderLayout.CENTER); frame1.add(buttonPanel2, BorderLayout.PAGE_END); frame1.pack(); }// end KeyListener keyListener = new KeyListener() { @Override public void keyTyped(KeyEvent e) { } @Override public void keyPressed(KeyEvent e) { keyCode = e.getKeyCode(); if (!(keyCode >= 48 && keyCode <= 57) && !(keyCode >= 96 && keyCode <= 105) && !(keyCode >= 37 && keyCode <= 40) && !(keyCode == 127 || keyCode == 8)) { txtID.setEditable(false); } } @Override public void keyReleased(KeyEvent e) { txtID.setEditable(true); } }; class RowListener implements ListSelectionListener { @Override public void valueChanged(ListSelectionEvent event) { if (event.getValueIsAdjusting()) { rowIndex = table.getSelectedRow(); if (data[rowIndex][0] == null || data[rowIndex][0] == "") { btnEdit.setEnabled(false); btnDelete.setEnabled(false); } else { btnEdit.setEnabled(true); btnDelete.setEnabled(true); } } } } class ButtonHandler implements ActionListener { @Override public void actionPerformed(ActionEvent e) { if (e.getActionCommand().equals("Login")) { txtID.setText(""); txtName.setText(""); txtCourse.setText(""); txtProfessor.setText(""); txtHelp.setText(""); txtDate.setText(dateFormat.format(date)); frame1.setTitle("Add Student data"); // title bar name for add frame1.setVisible(true); } else if (e.getActionCommand().equals("EDIT")) { txtID.setText(data[rowIndex][0] + ""); txtName.setText(data[rowIndex][1] + ""); txtCourse.setText(data[rowIndex][2] + ""); txtProfessor.setText(data[rowIndex][3] + ""); txtHelp.setText(data[rowIndex][4] + ""); txtDate.setText(data[rowIndex][5] + ""); txtID.setEditable(false); frame1.setTitle("Edit Student data"); btnAddInput.setActionCommand("Edit2"); btnAddInput.setText("ACCEPT"); frame1.setVisible(true); } else if (e.getActionCommand().equals("DELETE")) { int confirm = JOptionPane.showConfirmDialog(frame, "ARE YOU SURE?", "CONFIRM", JOptionPane.YES_NO_OPTION); if (confirm == 0) { rowIndex = table.getSelectedRow(); rowNumber = 0; noOfStudents--; for (int i = 0; i <= 10; i++) { if (rowIndex != i && i <= noOfStudents) { data[rowNumber][0] = data[i][0]; data[rowNumber][1] = data[i][1]; data[rowNumber][2] = data[i][2]; data[rowNumber][3] = data[i][3]; data[rowNumber][4] = data[i][4]; data[rowNumber][5] = data[i][5]; rowNumber++; } else if (rowIndex != i && i > noOfStudents) { data[rowNumber][0] = ""; data[rowNumber][1] = ""; data[rowNumber][2] = ""; data[rowNumber][3] = ""; data[rowNumber][4] = ""; data[rowNumber][5] = ""; rowNumber++; } } if (noOfStudents == 1000) { btnAdd.setEnabled(false); } else { btnAdd.setEnabled(true); } if (noOfStudents == 0) { btnDelete.setEnabled(false); btnEdit.setEnabled(false); } else { btnDelete.setEnabled(true); btnEdit.setEnabled(true); } rowIndex = table.getSelectedRow(); if (data[rowIndex][0] == null || data[rowIndex][0] == "") { btnEdit.setEnabled(false); btnDelete.setEnabled(false); } else { btnEdit.setEnabled(true); btnDelete.setEnabled(true); } table.updateUI(); } } else if (e.getActionCommand().equals("AddInput")) { if (txtID.getText().isEmpty() || txtName.getText().isEmpty() || txtCourse.getText().isEmpty()// / || txtProfessor.getText().isEmpty() || txtHelp.getText().isEmpty()) { JOptionPane.showMessageDialog(null, "PLEASE FILL IN THE BLANKS.", "ERROR!", JOptionPane.ERROR_MESSAGE); } else { int dup = 0; for (int i = 0; i < 10; i++) { if (txtID.getText().equals(data[i][0])) { JOptionPane.showMessageDialog(null, "ID NUMBER ALREADY EXISTS.", "ERROR!", JOptionPane.ERROR_MESSAGE); dup++; } } if (dup == 0) { rowIndex = table.getSelectedRow(); data[noOfStudents][0] = txtID.getText(); data[noOfStudents][1] = txtName.getText(); data[noOfStudents][2] = txtCourse.getText(); data[noOfStudents][3] = txtProfessor.getText(); data[noOfStudents][4] = txtHelp.getText(); data[noOfStudents][5] = txtDate.getText(); table.updateUI(); frame1.dispose(); noOfStudents++; if (noOfStudents == 50){ btnAdd.setEnabled(false); } else { btnAdd.setEnabled(true); } if (data[rowIndex][0] == null) { btnEdit.setEnabled(false); btnDelete.setEnabled(false); } else { btnEdit.setEnabled(true); btnDelete.setEnabled(true); } } } table.updateUI(); }else if(e.getActionCommand().equals("Save")){ try { PrintWriter out = new PrintWriter("Tutor.txt"); for(int i = 0; i < 25; i++) { for(int j = 0; j < 7; j++) { out.print(data[i][j]); out.print(", "); if(j == 6){ out.println(); } } out.flush(); }} catch (FileNotFoundException ex) { } } else if (e.getActionCommand().equals("Logout")) { int confirm = JOptionPane.showConfirmDialog(frame, "ARE YOU SURE?", "CONFIRM", JOptionPane.YES_NO_OPTION); if (confirm == 0) { rowIndex = table.getSelectedRow(); rowNumber = 0; txtDate2.setText(dateFormat.format(date)); } } if (txtID.getText().isEmpty() || txtName.getText().isEmpty() || txtCourse.getText().isEmpty() || txtProfessor.getText().isEmpty() || txtHelp.getText().isEmpty()|| txtHelp.getText().isEmpty()) { } else { data[rowIndex][0] = txtID.getText(); data[rowIndex][1] = txtName.getText(); data[rowIndex][2] = txtCourse.getText(); data[rowIndex][3] = txtProfessor.getText(); data[rowIndex][4] = txtHelp.getText(); data[rowIndex][5] = txtDate.getText(); data[rowIndex][6] = txtDate2.getText(); frame1.dispose(); } table.updateUI(); } } class JTextFieldLimit extends PlainDocument { private int limit; JTextFieldLimit(int limit) { super(); this.limit = limit; } JTextFieldLimit(int limit, boolean upper) { super(); this.limit = limit; } @Override public void insertString(int offset, String str, AttributeSet attr) throws BadLocationException { if (str == null) { return; } if ((getLength() + str.length()) <= limit) { super.insertString(offset, str, attr); } } } public static void main(String[] args) { new MainGUI(); } } </code></pre>

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