Develop Reference

Copying (some columns of) a JTable to a new JTable

I have a JTable displayed in a frame. This table must remain unmodified for
later processing. At some point I want to show a column reduced version of this
table in a dialog. So I make a copy of the original table in creating a new
TableModel and TableColumnModel, thereby skipping the columns not needed.
Everything is fine until the dialog is set to visible. Then I run into an
endless error loop, starting with an "ArrayIndexOutOfBoundsException: 3 >= 2".
If 3 is the index to a table row, then it's indeed too large.
As the reduced table has only two columns, a column index of 2 would already exceed. Checking the columns with
getColumnCount() shows that the values are ok.
I suspect my copyTable method to be the culprit, but have no idea where the 3
index is coming from.
Instead of filling the rows of the table's model one by one, I succeeded using DefaultTableModel.addColumn(Object columnName, Object[] columnData) as suggested here. Then, however, I lose the columns' width information. Hence I would still like to know my fault in the current code.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;
public class CopyTable extends JFrame {
public static final long serialVersionUID = 100L;
public CopyTable() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
JTable table= createTable();
JScrollPane scroll= new JScrollPane(table);
add(scroll, BorderLayout.CENTER);
JButton b= new JButton("Show dialog");
b.addActionListener(e -> createAndShowDialog(table));
add(b, BorderLayout.SOUTH);
setSize(table.getColumnModel().getTotalColumnWidth()+11, 240);
setVisible(true);
}
static public void main(String args[]) {
EventQueue.invokeLater(CopyTable::new);
}
// #param columns Indices of columns to be copied into the new table.
public JTable copyTable(JTable table, int... columns) {
DefaultTableModel tblModel= new DefaultTableModel(0, columns.length);
DefaultTableModel oldModel= (DefaultTableModel)table.getModel();
Object[] row= new Object[columns.length];
int iRow= 0;
while (iRow<oldModel.getRowCount()) {
for (int i=0; i<columns.length; i++) {
row[i]= oldModel.getValueAt(iRow, columns[i]);
}
tblModel.addRow(row);
iRow++;
}
DefaultTableColumnModel colModel= new DefaultTableColumnModel();
DefaultTableColumnModel oldColModel=
(DefaultTableColumnModel)table.getColumnModel();
for (int i=0; i<columns.length; i++) {
colModel.addColumn(oldColModel.getColumn(columns[i]));
/* Creating a new column didn't help.
TableColumn tc= new TableColumn();
tc= oldColModel.getColumn(columns[i]);
colModel.addColumn(tc);
*/
}
return new JTable(tblModel, colModel);
}
private void createAndShowDialog(JTable table) {
JTable tbl = copyTable(table, 0, 3); // Copy only columns 0 and 3.
JOptionPane.showMessageDialog(this, ""+tbl.getModel().getRowCount()+", "+
tbl.getModel().getColumnCount()+", "+
tbl.getColumnModel().getColumnCount(),
"Checking row/column count",
JOptionPane.INFORMATION_MESSAGE);
JDialog dlg= new JDialog(this, "Reduced table", true);
dlg.setLocationRelativeTo(this);
JScrollPane scroll = new JScrollPane(tbl);
dlg.add(scroll, BorderLayout.CENTER);
dlg.pack();
dlg.setVisible(true);
}
private JTable createTable() {
String headers[] = {"Fruit", "Colour", "Count", "Price"};
Object data[][] = {
{"Apple", "Green", 6, .3},
{"Banana", "Yellow", 3, .4},
{"Cherry", "Red", 10, 1.1}
};
DefaultTableModel model = new DefaultTableModel(data, headers) {
public Class<?> getColumnClass(int column) {
Class<?> returnValue;
if (column>=0 && column<getColumnCount() && getValueAt(0,column)!=null)
returnValue= getValueAt(0, column).getClass();
else
returnValue= Object.class;
return returnValue;
}
};
JTable tbl= new JTable(model);
TableColumnModel tcm= tbl.getColumnModel();
int[] width= new int[] {60, 50, 40, 40};
for (int i=0; i<headers.length; i++) {
tcm.getColumn(i).setPreferredWidth(width[i]);
tcm.getColumn(i).setWidth(width[i]);
}
return tbl;
}
}
Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 3 >= 2
at java.base/java.util.Vector.elementAt(Vector.java:466)
at java.desktop/javax.swing.table.DefaultTableModel.getValueAt(DefaultTableModel.java:661)
at java.desktop/javax.swing.JTable.getValueAt(JTable.java:2763)
at java.desktop/javax.swing.JTable.prepareRenderer(JTable.java:5780)
at java.desktop/javax.swing.plaf.basic.BasicTableUI.paintCell(BasicTableUI.java:2207)
at java.desktop/javax.swing.plaf.basic.BasicTableUI.paintCells(BasicTableUI.java:2109)
at java.desktop/javax.swing.plaf.basic.BasicTableUI.paint(BasicTableUI.java:1905)
at java.desktop/javax.swing.plaf.ComponentUI.update(ComponentUI.java:161)
at java.desktop/javax.swing.JComponent.paintComponent(JComponent.java:852)
java 18

There is no need to copy the TableModel (they are shareable by design) - all you need is a new TableColumnModel containing clones of the original: note that the relevant coordinate system is the model index.
Example:
TableColumnModel sourceColumnModel = sourceTable.getColumnModel();
DefaultTableColumnModel reducedColumnModel = new DefaultTableColumnModel();
for (int i = 0; i < sourceColumnModel.getColumnCount(); i++) {
TableColumn sourceColumn = sourceColumnModel.getColumn(i);
int modelIndex = sourceColumn.getModelIndex();
if (modelIndex % 2 == 0) { // replace with your condition
TableColumn column = new TableColumn(modelIndex, sourceColumn.getPreferredWidth());
column.setHeaderValue(sourceColumn.getHeaderValue());
reducedColumnModel.addColumn(column);
}
}
JTable reducedTable = new JTable(sourceTable.getModel(), reducedColumnModel);

#g00se
Your solution works. Thank you. The only drawback is that removing columns from the TableColumnModel doesn't remove them from the TableModel. So I added the following to your code
int icnt= oldModel.getRowCount();
for (int j=0; j<icnt; j++) {
Vector<?> vec= (Vector<?>)data.get(j);
for (int i=columns.length-1; i>=0; i--) {
vec.removeElementAt(columns[i]);
}
data.setElementAt(vec, j);
}
((DefaultTableModel)result.getModel()).setDataVector(data, headers);
return result;
But due to lack of Generics knowledge, I cannot make the code compile. Still an idea for that?
Just copying/creating a new model would avoid any removal. So I am still curious as for my original error.
Edit
----------------------------------------------------------
Generics:
Vector<Vector<Object>> data = ...
...
Vector<Object> vec= data.get(j);
----------------------------------------------------------
Finally I got my original version to work. colModel.addColumn(oldColModel.getColumn(columns[i])); passes only a reference of the column. But one has to create a new instance for each column in the new table.
// #param columns Indices of columns to be copied into the new table.
public JTable copyTable(JTable table, int... columns) {
DefaultTableModel oldModel= (DefaultTableModel)table.getModel();
DefaultTableModel tblModel= new DefaultTableModel(0, columns.length) {
public Class<?> getColumnClass(int column) {
Class<?> returnValue;
if (column>=0 && column<getColumnCount() && getValueAt(0,column)!=null)
returnValue= getValueAt(0, column).getClass();
else
returnValue= Object.class;
return returnValue;
}
};
Object[] row= new Object[columns.length];
int icnt= oldModel.getRowCount();
for (int i=0; i<icnt; i++) {
for (int j=0; j<columns.length; j++) {
row[j]= oldModel.getValueAt(i, columns[j]);
}
tblModel.addRow(row);
}
DefaultTableColumnModel oldColModel=
(DefaultTableColumnModel)table.getColumnModel();
DefaultTableColumnModel colModel= new DefaultTableColumnModel();
for (int i=0; i<columns.length; i++) {
// colModel.addColumn(oldColModel.getColumn(columns[i])); // Endless err loop
TableColumn tc= oldColModel.getColumn(columns[i]);
TableColumn tcNew= new TableColumn(i, tc.getPreferredWidth(),
tc.getCellRenderer(), tc.getCellEditor());
tcNew.setHeaderValue(tc.getHeaderValue());
colModel.addColumn(tcNew);
}
return new JTable(tblModel, colModel);
}
private void createAndShowDialog(JTable table) {
JTable tbl = copyTable(table, 0, 1, 3); // Copy only columns 0, 1 and 3.
JDialog dlg= new JDialog(this, "Reduced table", true);
JScrollPane scroll = new JScrollPane(tbl);
scroll.setPreferredSize(
new Dimension(tbl.getColumnModel().getTotalColumnWidth(), 80));
dlg.add(scroll, BorderLayout.CENTER);
dlg.pack();
dlg.setLocationRelativeTo(this);
dlg.setVisible(true);
}

I can't say I know quite why you get that exception, but this is a possible problem-free alternative, involving cloning the table then removing unwanted columns. This is based on the intuitive ascending ordering of required columns. Obviously the logic could be made easier by passing an array of columns to be removed rather than retained.
// #param columns Indices of columns to be copied into the new table.
public JTable copyTable(JTable table, int... columns) {
DefaultTableModel oldModel = (DefaultTableModel) table.getModel();
#SuppressWarnings("unchecked")
Vector<? extends Vector> data = (Vector<? extends Vector>) oldModel.getDataVector().clone();
Vector<Object> headers = new Vector<>();
TableColumnModel cmSource = table.getColumnModel();
for (int i = 0; i < table.getColumnModel().getColumnCount(); i++) {
headers.add(cmSource.getColumn(i).getIdentifier());
}
JTable result = new JTable(data, headers);
TableColumnModel cmTarget = result.getColumnModel();
Set<Integer> columnsToCopy = new HashSet<>();
for (int i = columns.length; --i >= 0;) {
columnsToCopy.add(columns[i]);
}
for (int i = cmTarget.getColumnCount(); --i >= 0;) {
if (!columnsToCopy.contains(i)) {
cmTarget.removeColumn(cmTarget.getColumn(i));
}
}
return result;
}

Getting old values from Jtable

I am facing a strange problem with the Jtable. I have a small standalone java application in which I have used Jtable that shows data that is retrieved from database. User can view and edit the data. Once he edit the cell and presses the update button then the edited values will be updated in the database. Now what happening is for the first time when user edit the data and click on update button then the values are properly persisted in the database and user gets out of the module. But again if he/she goes to the same module and edits some more cells and click on update button then in back end i get old value from those cells although the Jtable shows the latest updated values in the cells.
Below is the code.
private JTable jt;
private TableRowSorter<TableModel> tableSorter;
private Dao dao=new Dao();
updateDetails.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
boolean isSuccessful = true;
int rowCount = jt.getRowCount();
List<EmployeeMaster> empMasterList = new ArrayList<>();
int j = 0;
for (int i = 0; i < rowCount; i++) {
EmployeeMaster master = new EmployeeMaster();
j = 0;
try {
master.setEmpId(Long.parseLong((String) jt.getValueAt(i, j)));
j++;
compId.setName(Long.parseLong((String) jt.getValueAt(i, j)));
j++;
compId.setNumber((String) jt.getValueAt(i, j));
j++;
empMasterList.add(master);
}
dao.updateAllEmpDetails(empMasterList);
homePanel.setVisible(true);
UpdateEmp.setVisible(false);
}
}
});
getDataFromDBtoJtable.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
List<EmployeeMaster> empMasterList = dao.getAllEmpDetails();
String data[][] = new String[empMasterList.size()][3];
int i = 0;
int j = 0;
for (EmployeeMaster employeeMaster : empMasterList) {
j = 0;
data[i][j] = String.valueOf(employeeMaster.getEmpId());
j++;
data[i][j] = String.valueOf(employeeMaster.getName());
j++;
data[i][j] = String.valueOf(employeeMaster.getNumber());
i++;
}
String column[] = { "ID", "Name", "Number"};
jt = new JTable(data, column) {
public boolean isCellEditable(int row, int column) {
if (column == 0 || column == 1 || column == 2)
return false;
else
return true;
};
};
tableSorter = new TableRowSorter<TableModel>(jt.getModel());
jt.setBounds(12, 12, 1200, 400);
jt.setRowSorter(tableSorter);
homePanel.setVisible(false);
UpdateEmp.setVisible(true);
JScrollPane pane = new JScrollPane(jt);
pane.setBounds(1, 40, 1150, 300);
setBounds(0, 0, 2000, 800);
UpdateEmp.add(pane);
}
});
updateDetails -> button to get the data from jtable and update it in database
getDataFromDBtoJtable -> button to get data from Database and show it in Jtable
Whenever user hits the updateDetails i am updating the database and forcing user to get out of the module. So everytime whenever user get into jtable module he/she gets new Jtable instance. But still unable to identify what's going wrong.

JTable select and deselect not working

I have a problem with my JTable. Firstly I selected some entries in my table. However when I deselect some of them, the table could not understand it.
Example scenario: I select job1 and 2 for the testing after that I change my mind and de-select job2. But in the result I saw job1 job1 and job2 ( job 1 seen 2 times and even though I dis-select job 2 I saw them.) Or after selected all the jobs ( choose all button) I want to deselect all of them (Clear button) when I click clear all the table seems empty. It is good but somehow the background of the program still protect the all old selection. How can I solve this?
Try:
I created the row of my table by read csv file.
public class JobSelectionListPanel extends JPanel {
private static final long serialVersionUID = 5198916547962359735L;
private static JobSelectionListPanel INSTANCE = new JobSelectionListPanel();
public static JobSelectionListPanel getInstance() {
return INSTANCE;
}
private JTable table;
private JButton next, back, btnClear, btnNewButton, btnChooseAll;
private JobList fnnJobList = new JobList();
private JobSelectionListPanel() {
table = new JTable();
JScrollPane scrollPane = new JScrollPane(table);
table.setBorder(new CompoundBorder());
// Read all FNN jobs from file
try {
fnnJobList.readFromFile("rules.csv");
} catch (IOException e1) {
System.out.println("You are not able to read the rules.csv file");
}
// Create ArrayList of JobNames
Object[][] initialData = new Object[fnnJobList.size()][1];
int i = 0;
for (Job jobDes : fnnJobList) {
initialData[i][0] = (Object) jobDes.getJobname();
i++;
}
String[] columnNames = new String[] { "", "Your preferences" };
table.setModel(new DefaultTableModel(initialData, columnNames) {
private static final long serialVersionUID = 1L;
#SuppressWarnings("rawtypes")
Class[] columnTypes = new Class[] { Object.class, Boolean.class };
#SuppressWarnings({ "unchecked", "rawtypes" })
public Class getColumnClass(int columnIndex) {
return columnTypes[columnIndex];
}
});
table.getColumnModel().getColumn(1).setPreferredWidth(80);
table.getColumnModel().getColumn(1).setMinWidth(40);
table.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
table.setCellSelectionEnabled(true);
I user want to choose all rows then I implemented this.
btnChooseAll = new JButton("Choose all");
btnChooseAll.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
DefaultTableModel chooseAllData = (DefaultTableModel) table.getModel();
if (DeviceGroups.DeviceAList.size() == 0 || DeviceGroups.DeviceBList.size() == 0
|| DeviceGroups.DeviceCList.size() == 0 || DeviceGroups.DeviceDList.size() == 0)
JOptionPane.showMessageDialog(null,
"You should choose at least 1 device for each test device to apply this test case", "Invalid OPTION",
JOptionPane.ERROR_MESSAGE);
else
for (int i = 0; i < chooseAllData.getRowCount(); i++) {
for (int j = 1; j < chooseAllData.getColumnCount(); j++) {
chooseAllData.setValueAt(true, i, j);
}
}
}
});
For clear all preferences :
btnClear = new JButton("Clear all");
// Clear button create a model of JTable and delete all the rows of table!!
btnClear.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
DefaultTableModel clearTableData = (DefaultTableModel) table.getModel();
for (int i = 0; i < clearTableData.getRowCount(); i++) {
for (int j = 1; j < clearTableData.getColumnCount(); j++) {
clearTableData.setValueAt(null, i, j);
}
}
}
});

I see the following problem in your code: mixing up view indexes and model indexes. This is the offending snippet:
for (int i = 0; i < table.getRowCount(); i++) {
if (table.getValueAt(i, 1) != null) {
if (((Boolean) table.getValueAt(i, 1)).booleanValue()) {
String jobName = (((DefaultTableModel) table.getModel()).getValueAt(i, 0).toString());
You are using the i variable to denote view row indices, since you are checking values in this statement: table.getValueAt(i, 1) != null.
But then a bit further you are using i to index the model:
String jobName = ((DefaultTableModel) table.getModel()).getValueAt(i, 0).toString();
If i is to be a view index, you need to convert it to a model index before indexing the model:
String jobName = ((DefaultTableModel) table.getModel()).getValueAt(table.convertRowIndexToModel(i), 0).toString();
Also, when columns would be switched around in the view (ie on screen in your GUI), the following will probably not work as intended:
table.getValueAt(i, 1) != null
You most likely mean to say, get the second column value in the model, not the view. Best rewrite then as
table.getValueAt(i, table.convertColumnIndexToView(1)) != null

Calculate the sum of a column and put it on that jtable

How can I calculate sum of price column in jTable and put sum of them at the end of the jTable. Can you give me a sample code?
public class IncomeReport extends JFrame {
private AccountFacade service = new AccountFacade();
void init() {
String[] columnNames = {"مبلغ", "محل درآمد ", "منبع"};
List list = service.incomeReportFacade();
Object[][] model = new Object[list.size()][];
for (int i = 0; i < list.size(); i++) {
model[i] = (Object[]) list.get(i);
}
JTable table = new JTable(model, columnNames) {
DefaultTableCellRenderer renderRight = new DefaultTableCellRenderer();
{
// initializer block
renderRight.setHorizontalAlignment(SwingConstants.RIGHT);
}
#Override
public TableCellRenderer getCellRenderer(int arg0, int arg1) {
return renderRight;
}
};

Try something like this. Get the model, and use the DefaultTableModel#getValueAt() method.
Jtable table = new Jtable();
DefaultTableModel model = (DefaultTableModel)table.getModel();
double total = 0;
int column = 2; // example
for (int i = 0; i < model.getRowCount(); i++){
total += model.getValueAt(i, column); // getValueAt(row, column)
}
Object[] row = {"", "", total};
model.addRow(row);

If you need a total that is dynamically kept up to date then you will need to either override your TableModel to provide the sum for the final row, or will need to listener for changes to the model and update the last row with the sum.
Customizing your own TableModel would also allow you the ability to make your summary row uneditable so while this might be more work, it provides much more flexibility.

JTable hide and show columns

I want to add some columns to a table (Swing JTable). Some of them will have a default size (e.g. 250), others will be hidden (so their size will be 0). I use this code:
model = new DefaultTableModel();
table = new JTable(model);
setAutoResizeMode(AUTO_RESIZE_OFF);
for (int i = 1; i < COLUMN_NAMES.length; i++) {
model.addColumn(COLUMN_NAMES[i]);
if (show[i]) show(index);
else hide(index);
}
........
private void hide(int index) {
TableColumn column = getColumnModel().getColumn(index);
column.setMinWidth(0);
column.setMaxWidth(0);
column.setWidth(0);
column.setPreferredWidth(0);
doLayout();
}
private void show(int index) {
final int width = 250;
column.setMinWidth(15);
column.setMaxWidth(width);
column.setWidth(width);
column.setPreferredWidth(width);
doLayout();
}
the problem is when the table is displayed, all the columns are showed (none is hidden) and their size is not 250 but they have all the same size.
How can I get the wanted effect?

I think you have named your methods incorrectly, when you want to hide a column you will set
column.setMinWidth(0);
column.setMaxWidth(0);
column.setPreferredWidth(0);
but in your code you are doing this when you want to show a column which is exactly opposite.
Also there is no need to call this "setWidth" method on a TableColumn, read TableColumn#setWidth(int).

JTable#removeColumn remove Column only from JTable view, more in this example

instead of re-inventing the wheel you might consider to use JXTable (in the SwingX project) which supports hidden columns, comlete with a ui-control to allow users hiding/showing them dynamically - and a bunch of other useful thingies :).

try this something like this for example:
myTableModel = new DefaultTableModel();
myTableModel.setColumnIdentifiers(new Object[]{"ID", "Name"});
JTable myTable = new JTable(myTableModel);
// remember to save the references
TableColumn myTableColumn0 = guiLoteryNumbersTable.getColumnModel().getColumn(0);
TableColumn myTableColumn1 = guiLoteryNumbersTable.getColumnModel().getColumn(1);
//...
// remove temporary the column ("hide")
myTable.getColumnModel().removeColumn(myTableColumn1);
// then you restore that column when you need it ("show")
myTable.getColumnModel().addColumn(myTableColumn1);
That's the best way I know to hide a column.

HashMap<String,TableColumn> hashMap_columns = new HashMap<String,TableColumn>();
DefaultTableColumnModel defaultTableColumnModel = (DefaultTableColumnModel)jtable.getColumnModel();
Enumeration<TableColumn> enumeration = defaultTableColumnModel.getColumns();
while (enumeration.hasMoreElements())
{
TableColumn tableColumn = enumeration.nextElement();
hashMap_columns.put((String)tableColumn.getIdentifier(),tableColumn);
}
public void setColumnVisible(String identifier, boolean setVisible)
{
TableColumn tableColumn = hashMap_columns.get(identifier);
if (setVisible)
{
// using a sorted map removes the need to check column index/position
SortedMap<Integer,TableColumn> sortedMap = new TreeMap<Integer,TableColumn>();
// retreive all visible columns
Enumeration<TableColumn> enumeration = defaultTableColumnModel.getColumns();
while (enumeration.hasMoreElements())
{
TableColumn column = enumeration.nextElement();
sortedMap.put(column.getModelIndex(),column);
}
// add the column of interest to the sorted map
sortedMap.put(tableColumn.getModelIndex(),tableColumn);
// remove all visible columns
for (TableColumn column: sortedMap.values())
{
defaultTableColumnModel.removeColumn(column);
}
// add all previously visible columns as well as the column of interest
for (TableColumn column: sortedMap.values())
{
defaultTableColumnModel.addColumn(column);
}
}
else
{
defaultTableColumnModel.removeColumn(tableColumn);
}
}

public class TableColumnHider {
private final JTable table;
private final TableColumnModel tcm;
private final Map hiddenColumns;
public TableColumnHider(JTable table) {
this.table = table;
tcm = table.getColumnModel();
hiddenColumns = new HashMap();
}
public void hide(String columnName, String keySig) {
int index = tcm.getColumnIndex(columnName);
TableColumn column = tcm.getColumn(index);
hiddenColumns.put(columnName, column);
hiddenColumns.put(keySig + columnName, new Integer(index));
tcm.removeColumn(column);
}
public void show(String columnName, String keySig) {
Object o = hiddenColumns.remove(columnName);
if (o == null) {
return;
}
tcm.addColumn((TableColumn) o);
o = hiddenColumns.remove(keySig + columnName);
if (o == null) {
return;
}
int column = ((Integer) o).intValue();
int lastColumn = tcm.getColumnCount() - 1;
if (column < lastColumn) {
tcm.moveColumn(lastColumn, column);
}
}
}