How to implement editable field in table to restrict to accept fixed length

[Karnati Sudhakar]

Hi All,

I have a JTable in which 4th column is editable but i want to make this column to accept only fixed length input means user should not be able to enter data more than what is fixed at execution time for that cell.

Regards
Sudhakar

[Darryl Burke]

Just another cross poster.
http://forums.sun.com/thread.jspa?threadID=5355748

[Maneesh Godbole]

Originally posted by Darryl Burke:
Just another cross poster.
http://forums.sun.com/thread.jspa?threadID=5355748

Sudhakar,
After ~88 posts you should know better.
Please do take out time to go through this.

[Karnati Sudhakar]

Sudhakar,
After ~88 posts you should know better.
Please do take out time to go through this.

Maneesh,

I am sorry.I was unaware of that policy.I was in hurry to get the answer.I never thought about the people who answer our queries and their precious time.Once again many thanks to people who answer our questions(Sometimes stupid) very patiently.

What should i do now? I did not get the answer either here or there?
Please help me..

Regards
Sudhakar

[Karnati Sudhakar]

I tried to extend the DefaultCellEditor and created a FixedLengthTextField for the 4th column.But it is not working last editable column is accepting unlimited data.

Example1.java

public class Example1 extends AbstractTableModel implements ActionListener {
 
    private boolean DEBUG = true;
    Object[][] data = null;
    String[] columnNames = null;
    JFrame frame = new JFrame("Sample Demo");
    JPanel panel1 = new JPanel();
    JLabel label1 = new JLabel();
 
    public Example1() {
 
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        initComponents1();
    }
 
    private void initComponents1() {
 
        JRadioButtonMenuItem[] rbMenuItem;
        JMenu menu;
        JMenuItem menuItem;
        JMenuBar greenMenuBar;
 
        frame.setSize(Integer.MAX_VALUE, Integer.MAX_VALUE);
 
        menu = new JMenu("Sample Menu");
 
        rbMenuItem = new JRadioButtonMenuItem[Main.list1.size()];
        greenMenuBar = new JMenuBar();
        frame.add(greenMenuBar);
 
        menu = new JMenu("File");
        greenMenuBar.add(menu);
 
        menuItem = new JMenuItem("Select from following");
        menu.add(menuItem);
 
        menu.addSeparator();
 
        ButtonGroup group = new ButtonGroup();
 
        for (int i = 0; i < Main.list1.size(); i++) {
 
            String name = (String) Main.list1.get(i);
 
            rbMenuItem[i] = new JRadioButtonMenuItem(name);
            rbMenuItem[i].setSelected(false);
            rbMenuItem[i].setActionCommand(name);
            rbMenuItem[i].addActionListener(this);
            group.add(rbMenuItem[i]);
            menu.add(rbMenuItem[i]);
        }
 
        greenMenuBar.add(menu);
        frame.setJMenuBar(greenMenuBar);
        frame.setVisible(true);
 
    }
 
    public void actionPerformed(ActionEvent e) {
 
        String layoutName = e.getActionCommand();
 
        columnNames = new String[]{"Property Name",
            "Start",
            "Length", "Enter Your Value Here"
        };
 
        int m = 0;
 
        for (int i = 0; i < Main.list.size(); i++) {
            if (((PropertyStore) Main.list.get(i)).LayoutName.equals(layoutName)) {
 
                data = new Object[m + 1][4];
                m++;
 
            }
        }
        int n = 0;
 
        for (int i = 0; i < Main.list.size(); i++) {
            if (((PropertyStore) Main.list.get(i)).LayoutName.equals(layoutName)) {
                data[n][0] = ((PropertyStore) Main.list.get(i)).PropertyName;
                data[n][1] = ((PropertyStore) Main.list.get(i)).Start;
                data[n][2] = ((PropertyStore) Main.list.get(i)).Length;
                [B]data[n][3] = new Object();[/B]
                n++;
            }
        }
        fireTableDataChanged();
 
        JTable table = new JTable(data, columnNames);
 
[B]        int vColIndex = 3;
        TableColumn col = table.getColumnModel().getColumn(vColIndex);
        col.setCellEditor(new MyTableCellEditor(4));[/B]
 
//        table.getColumn(4).setCellEditor();
        table.setModel(this);
        fireTableDataChanged();
        table.setPreferredScrollableViewportSize(new Dimension(500, 70));
        JScrollPane scrollPane = new JScrollPane(table);
 
        JButton saveButton = new JButton("Save");
        JButton saveasButton = new JButton("Save As");
 
        JPanel buttonPane = new JPanel();
        buttonPane.setLayout(new BoxLayout(buttonPane, BoxLayout.LINE_AXIS));
        buttonPane.setBorder(BorderFactory.createEmptyBorder());
        buttonPane.add(Box.createHorizontalGlue());
        buttonPane.add(saveButton);
        buttonPane.add(Box.createRigidArea(new Dimension(10, 0)));
        buttonPane.add(saveasButton);
 
        buttonPane.setOpaque(false);
        scrollPane.setOpaque(false);
 
        frame.getContentPane().add(buttonPane);
        frame.validate();
        frame.getContentPane().add(scrollPane);
        frame.validate();
    }
 
    class MyTableCellEditor extends DefaultCellEditor {
        // This is the component that will handle the editing of the cell value
        int length;
        FixedLengthTextField component = null;
 
        protected MyTableCellEditor(int length1) {
            super(new FixedLengthTextField(length1));
            component = (FixedLengthTextField) getComponent();
            component = new FixedLengthTextField(this.length);
        }
 
        public Component getTableCellEditorComponent(JTable table,
                Object value, boolean isSelected,
                int row, int column) {
            FixedLengthTextField component =
                    (FixedLengthTextField) super.getTableCellEditorComponent(
                    table, value, isSelected, row, column);
            return component;
        }
    }
 
    public int getColumnCount() {
        return columnNames.length;
    }
 
    public int getRowCount() {
        return data.length;
    }
 
    public String getColumnName(int col) {
        return columnNames[col];
    }
 
    public Object getValueAt(int row, int col) {
        return data[row][col];
    }
 

 
    public Class getColumnClass(int c) {
        return getValueAt(0, c).getClass();
    }
 
    public boolean isCellEditable(int row, int col) {
        if (col < 3) {
            return false;
        } else {
            return true;
        }
    }
 
    public void setValueAt(Object value, int row, int col) {
        if (DEBUG) {
            System.out.println("Setting value at " + row + "," + col + " to " + value + " (an instance of " + value.getClass() + ")");
        }
        data[row][col] = value;
        fireTableCellUpdated(row, col);
 
        if (DEBUG) {
            System.out.println("New value of data:");
            printDebugData();
        }
    }
 
    @Override
    public void fireTableDataChanged() {
        super.fireTableDataChanged();
    }
 
    private void printDebugData() {
        int numRows = getRowCount();
        int numCols = getColumnCount();
 
        for (int i = 0; i < numRows; i++) {
            System.out.print("    row " + i + ":");
            for (int j = 0; j < numCols; j++) {
                System.out.print("  " + data[i][j]);
            }
            System.out.println();
        }
        System.out.println("--------------------------");
    }
}

FixedLengthTextField.java

import javax.swing.*;
public class FixedLengthTextField extends JTextField 
{
  
  public FixedLengthTextField(int length)
  {
   this(null, length);
  }
  
  public FixedLengthTextField(String text, int length) {
   super(new FixedLengthPlainDocument(length), text,length);
  }
}

FixedLengthPlainDocument.java

public class FixedLengthPlainDocument extends PlainDocument 
{
  
  private int maxLength;
   
  public FixedLengthPlainDocument(int maxLength) {
 this.maxLength = maxLength;
  }
  public void insertString(int offset, String str, AttributeSet a)
   throws BadLocationException {
   if(getLength() + str.length() > maxLength) {
//Toolkit.getDefaultToolkit().beep();
   }
   else {
 super.insertString(offset, str, a);
   }
  }   
  
}

Please help me..

Regards
Sudhakar

[Karnati Sudhakar]

should i override the method getColumnClass?

What kind of object should be assigned to the data value for the particular cell?

Regards
Sudhakar

[Karnati Sudhakar]

Any body please suggest me how to do it?

[Ulf Dittmer]

The code doesn't compile - it's missing the Main and PropertyStore classes. Post a simplified example that doesn't use those.

[Mikko Kohtamäki]

Confused, is your problem that when cell goes to edit mode (in that moment) you want set fixed length of characters for your editor component (eg. JTextField) ?

[Karnati Sudhakar]

Confused, is your problem that when cell goes to edit mode (in that moment) you want set fixed length of characters for your editor component (eg. JTextField) ?

Yes.I did this by overriding the isCellEditable method and setting the length of the editable cell there.

The code doesn't compile - it's missing the Main and PropertyStore classes. Post a simplified example that doesn't use those.

Thanks Ulf.Issue resolved.I used DefaultTableModel instead of AbstractTableModel.

Regards
Sudhakar