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Make JTable cells in specific column scrollable

I'm creating GUI in java using swing. I use JTable that looks like this.
I need to make cells of last column("Popis") to be scrollable as there will be description so String containing this description has variable lenght for each row.
This is how I created my JTable.
this.tableModel = new DefaultTableModel(
new Object[][] { },
new String[] {"ID", "Nazov", "Naplnena kapacita / kapacita", "Popis"}
);
this.table1.setModel(this.tableModel);
I add data to table using this.tablemodel.addRow();
Is there a way to make cells of last column of my table scrollable?

It would be difficult and awkward to embed a scrolling component inside a JTable. A common approach to showing long cell values is to make the cell’s tooltip (hover text) display the full value:
table1.setModel(tableModel);
table1.getColumnModel().getColumn(3).setCellRenderer(
new DefaultTableCellRenderer() {
#Override
public Component getTableCellRendererComponent(JTable table,
Object value,
boolean selected,
boolean focused,
int row,
int column) {
Component component = super.getTableCellRendererComponent(
table, value, selected, focused, row, column);
if (component instanceof JComponent) {
((JComponent) component).setToolTipText(
Objects.toString(value, null));
}
return component;
}
});
(Objects is the java.util.Objects class.)

It can be solved by creating private class that extends AbstractCellEditor and implements TableCellEditor. Then create and customize the scrollbar. Here is example.
public class MainForm {
private JTable table1;
private JPanel panel1;
private JTextArea text = new JTextArea();
public MainForm() {
text.setEditable(false);
DefaultTableModel tableModel = new DefaultTableModel(new Object[][]{}, new String[]{"Meno", "Priezvisko", "Datum", "Popis"});
table1.setModel(tableModel);
table1.setRowHeight(40);
tableModel.addRow(new Object[]{"Jaimi", "Parker", "2022", "fdjfadufaouifasoifjasifhasiofa \nasdasdasdasdasdasdas \nasdasdasdasdasdasd\nasdasdasdasd "});
tableModel.addRow(new Object[]{"William", "Mcdonald", "2021", "fdjfadufaouasfadfdsfafifasoifjasifhasiofa"});
tableModel.addRow(new Object[]{"Matt", "Ashley", "2020", "asfasfafdsfgdafgdfgasgsdg"});
tableModel.addRow(new Object[]{"Ariana", "Burns", "2019", "fdjfadufaouifasfdsgdgagsgsdgsdgsdagsdgsdgsdgsagsdgoifjasifhasiofa"});
TableColumn column = table1.getColumn("Popis");
column.setCellEditor(new HScrollableTCE());
}
public static void main(String[] args) {
JFrame frame = new JFrame("MainForm");
frame.setContentPane(new MainForm().panel1);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
private class HScrollableTCE extends AbstractCellEditor implements TableCellEditor
{
JScrollPane scroll = new JScrollPane(text, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
public Component getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int rowIndex, int vColIndex)
{
if (value != null) {
scroll.setHorizontalScrollBar(scroll.createHorizontalScrollBar());
scroll.getHorizontalScrollBar().setPreferredSize(new Dimension(0, 5));
scroll.setBorder(new EmptyBorder(0,0,0,0));
scroll.setToolTipText(value.toString());
text.setText(value.toString());
return scroll;
}
return null;
}
public Object getCellEditorValue()
{
return text.getText();
}
}
}

I want to change the Font Size at the time of writing in a cell in the Editable JTable

for this, I tried this method
table.setFont(new Font("Lucida Console", Font.PLAIN, 18));
but by using this I cannot find the appropriate Font at the time of Writing in the cell of the JTable.
I attach an image so you can find my question clearly .in this image u can see that at the time of writing font is small but after going to the next cell it becomes to change but I want that big font you can see that in image at the time of writing in the cell.

The problem is that table.setFont(new Font("Lucida Console", Font.PLAIN, 18)); will set the font of the cells when not being edited, it will not even set the font of the header. When editing, you have override the default setup by defining your own DefaultCellEditor. There are two ways to do so, the first (easier and cleaner) way is to create a JTextField and customize it the way you like and then pass it to the DefaultCellEditor constructor. The second (longer and not as clean) way is to override the getTableCellEditorComponent in the DefaultCellEditor and achieve the same result. I have included both solutions in a MCVE:
import java.awt.Color;
import java.awt.Font;
import javax.swing.DefaultCellEditor;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
public class Example extends JFrame {
private final JTable table;
private final String[] header = new String[]{"Column 0", "Column 1", "Column 2", "Column 3"};
private String[][] data = new String[][]{
{"(0,0)", "(1,0)", "(2,0)", "(3,0)"},
{"(0,1)", "(1,1)", "(2,1)", "(3,1)"},
{"(0,2)", "(1,2)", "(2,2)", "(3,2)"},
{"(0,3)", "(1,3)", "(2,3)", "(3,3)"}};
private final Font tableFont = new Font("Lucida Console", Font.PLAIN, 18);
public Example() {
table = new JTable(data, header);
table.getTableHeader().setFont(tableFont);//font of the header
table.setFont(tableFont);//set the font of the whole table
//Since each cell is editable, you could think about it as a JTextField. You can create a
//new JTextField and customize it. Then, you pass it as the new cell editor to the columns
//of the JTable.
JTextField textField = new JTextField();
textField.setFont(tableFont);//this is what you need.
//Extra changes, no boarder and selection colour is yellow... just to get the point across.
textField.setBorder(null);
textField.setSelectionColor(Color.YELLOW);
//Create DefaultCellEditor and pass the textfield to the constructor.
DefaultCellEditor customCellEditor = new DefaultCellEditor(textField);
//Loop through all the columns and set the cell editor as the customized one.
for (int i = 0; i < table.getColumnCount(); i++) {
table.getColumnModel().getColumn(i).setCellEditor(customCellEditor);
}
/*
OR, don't create a JTextField and use the following instead:
DefaultCellEditor customCellEditor2 = new DefaultCellEditor(new JTextField()) {
#Override
public java.awt.Component getTableCellEditorComponent(JTable table, Object value,
boolean isSelected, int row, int column) {
JTextField result = (JTextField) super.getTableCellEditorComponent(table, value,
isSelected, row, column);
result.setFont(tableFont);//this is what you need.
result.setBorder(null);
result.setSelectionColor(Color.YELLOW);
return result;
}
};
//Loop through all the columns and set the cell editor as the customized one.
for (int i = 0; i < table.getColumnCount(); i++) {
table.getColumnModel().getColumn(i).setCellEditor(customCellEditor2);
}
*/
//probably, you should make the height of the cells larger.
for (int i = 0; i < table.getRowCount(); i++) {
table.setRowHeight(i, 25);
}
add(new JScrollPane(table));
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
pack();
setVisible(true);
}
public static void main(String[] args) {
new Example();
}

Maybe you could check how many characters have been typed in and calculate approximately how big the font should be.
Calculation shouldn't be hard, is it? And then just change the size in this cell.

JTable: how to achieve custom rollover effect with TableCellRenderer

I already add a picture with JLabel in my JTable with TableCellRenderer. But how to add a border to the JLabel when mouse moves over the cell, on specific column and row?
This is the 1st renderer class:
public class RenderTabel implements TableCellRenderer{
#Override
public Component getTableCellRendererComponent(JTable table, Object
value,boolean isSelected, boolean hasFocus,int row, int column){
JLabel gambar=new JLabel();
String url="D:\\Kuliah Semester 4\\Pemrograman Berorientasi Objek\\DINUS BOOKSTORE\\image";
ImageIcon img=scalegmbr(url+"\\"+table.getModel().getValueAt(row, 0)+".png");
gambar.setIcon(img);
gambar.setText("");
gambar.setHorizontalAlignment(SwingConstants.CENTER);
table.setRowHeight(row, 50);
table.getColumnModel().getColumn(column).setPreferredWidth(80);
return gambar;
}
public ImageIcon scalegmbr(String file){
Image image=new ImageIcon(file).getImage();
return new ImageIcon(image.getScaledInstance(80,50,SCALE_SMOOTH));
}
}
This is 2nd renderer class:
public class RenderTabel1 implements TableCellRenderer{
#Override
public Component getTableCellRendererComponent(JTable table, Object
value,boolean isSelected, boolean hasFocus,int row, int column){
JLabel gambar=new JLabel();
String url="D:\\Kuliah Semester 4\\Pemrograman Berorientasi Objek\\DINUS BOOKSTORE\\image";
ImageIcon img=scalegmbr(url+"\\"+table.getModel().getValueAt(row, 0)+".png");
gambar.setIcon(img);
gambar.setText("");
gambar.setHorizontalAlignment(SwingConstants.CENTER);
gambar.setBorder(javax.swing.BorderFactory.createLineBorder(new java.awt.Color(200, 100, 52), 2));
table.setRowHeight(row, 50);
table.getColumnModel().getColumn(column).setPreferredWidth(80);
return gambar;
}
public ImageIcon scalegmbr(String file){
Image image=new ImageIcon(file).getImage();
return new ImageIcon(image.getScaledInstance(80,50,SCALE_SMOOTH));
}
}
and this is how I set the mouse enter and mouse clicked in my JTable:
private void tblbukuMouseEntered(java.awt.event.MouseEvent evt) {
// TODO add your handling code here:
tblbuku.getColumnModel().getColumn(6).setCellRenderer( new RenderTabel1());
}
private void tblbukuMouseExited(java.awt.event.MouseEvent evt) {
// TODO add your handling code here:
tblbuku.getColumnModel().getColumn(6).setCellRenderer( new RenderTabel());
}
But this adds a border to all cells in column 6 when mouse moves ofer a cell of that column. How to change it only into specific row and column when mouse entered that row and column?

So, for a particular column of your table, you want to paint a border on the cell that is hovered by the mouse (only the hovered cell, only in this column).
(edit: after clarification it appears that this question has been asked before -- I'm leaving my answer below as it might still help)
don't change the cell renderer dynamically, have only 1 renderer for that column, and handle that situation within the single renderer.
don't add listeners on the Component that is returned by the renderer: such listeners won't be triggered, as the component is only used for its paint()-ing logic.
instead, add a mouse motion listener on the table itself, and compute the coordinates of hovered cells with JTable's methods rowAtPoint and columnAtPoint, when mouse moves over table, or exits the area.
(irrelevant to problem at hand, but deserves a mention) Avoid creating a new JLabel for each call of your renderer, this is wasteful. Swing is single-thread, it's safe to reuse the same object (provided you don't forget to reset all its properties that might have changed between 2 calls)
Small demo that shows the effect:
import javax.swing.*;
import javax.swing.table.DefaultTableCellRenderer;
import java.awt.*;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
public class SimpleTableDemo extends JPanel {
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(SimpleTableDemo::createAndShowGUI);
}
private int
hoveredRow = -1,
hoveredColumn = -1;
SimpleTableDemo() {
super(new GridLayout(1,0));
String[] columnNames = {"First Name", "Last Name", "Sport", "# of Years", "Vegetarian"};
Object[][] data = {
{"Kathy", "Smith", "Snowboarding", 5, Boolean.FALSE},
{"John", "Doe", "Rowing", 3, Boolean.TRUE},
{"Sue", "Black", "Knitting", 2, Boolean.FALSE},
{"Jane", "White", "Speed reading", 20, Boolean.TRUE},
{"Joe", "Brown", "Pool", 10, Boolean.FALSE}
};
final JTable table = new JTable(data, columnNames);
table.setPreferredScrollableViewportSize(new Dimension(500, 70));
table.setFillsViewportHeight(true);
table.getColumn("Sport").setCellRenderer(new MyCellRenderer());
table.addMouseMotionListener(new MouseAdapter() {
public void mouseMoved(MouseEvent e) {
Point p = e.getPoint();
hoveredRow = table.rowAtPoint(p);
hoveredColumn = table.columnAtPoint(p);
table.repaint();
}
public void mouseExited(MouseEvent e) {
hoveredRow = hoveredColumn = -1;
table.repaint();
}
});
JScrollPane scrollPane = new JScrollPane(table);
add(scrollPane);
}
private static void createAndShowGUI() {
JFrame frame = new JFrame("SimpleTableDemo");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
SimpleTableDemo newContentPane = new SimpleTableDemo();
newContentPane.setOpaque(true);
frame.setContentPane(newContentPane);
frame.pack();
frame.setVisible(true);
}
private class MyCellRenderer extends DefaultTableCellRenderer {
#Override
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
JLabel label = (JLabel) super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
if (hoveredColumn == column && hoveredRow == row) {
label.setBorder(BorderFactory.createLineBorder(Color.GREEN, 2));
}
else {
label.setBorder(BorderFactory.createEmptyBorder(2, 2, 2, 2));
}
return label;
}
}
}
Note 1: I'm using the default cell renderer, unlike you, but the same idea applies. The demo above is a generic example, that will be more useful as example to keep here than a specific solution for your case (for example, in my interpretation of the problem, I understand the details about icon are irrelevant).
Note 2: In the demo I repaint the whole visible area each time, but if you want to optimize it should be possible to repaint only 2 cells, that's an entire new question, see here for help about that.

JTable all column aligned right

Is there a way to align all the column in jtable at the same time?
using this:
DefaultTableCellRenderer rightRenderer = new DefaultTableCellRenderer();
rightRenderer.setHorizontalAlignment( JLabel.RIGHT );
JTAB_TABLE.getColumnModel().getColumn(0).setCellRenderer( rightRenderer );
will let me align only one column but i need to align all.

Normally, a table contains different kinds of data, (Date, Number, Boolean, String) and it doesn't make sense to force all types of data to be right aligned.
If however you have a table with all the same type of data and you want to force the renderering of all columns to be the same, then you should probably use the same renderer. Assuming you are using the default renderer you can use:
DefaultTableCellRenderer renderer = (DefaultTableCellRenderer)table.getDefaultRenderer(Object.class);
renderer.setHorizontalAlignment( JLabel.RIGHT );

You can do so by overriding prepareRenderer(...) in JTable. This assumes that any custom renderers are JLabels (they're JLabels by default). You'd have to guard against it otherwise.
import java.awt.*;
import javax.swing.*;
import javax.swing.table.*;
public class TableDemo implements Runnable
{
public static void main(String[] args)
{
SwingUtilities.invokeLater(new TableDemo());
}
public void run()
{
JTable table = new JTable(5, 5)
{
#Override
public Component prepareRenderer(TableCellRenderer renderer,
int row, int col)
{
Component comp = super.prepareRenderer(renderer, row, col);
((JLabel) comp).setHorizontalAlignment(JLabel.RIGHT);
return comp;
}
};
table.setPreferredScrollableViewportSize(table.getPreferredSize());
JScrollPane scrollPane = new JScrollPane(table);
JFrame frame = new JFrame();
frame.getContentPane().add(scrollPane);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}

How to center in JTable cell a value?

How to center a value in JTable cell? I'm using Netbeans.

You need to customize the renderer. To center the first column you can do:
DefaultTableCellRenderer centerRenderer = new DefaultTableCellRenderer();
centerRenderer.setHorizontalAlignment( JLabel.CENTER );
table.getColumnModel().getColumn(0).setCellRenderer( centerRenderer );
To center all columns with String data you can do:
DefaultTableCellRenderer centerRenderer = new DefaultTableCellRenderer();
centerRenderer.setHorizontalAlignment( JLabel.CENTER );
table.setDefaultRenderer(String.class, centerRenderer);

Another good way to center all columns is with a loop:
for(int x=0;x<numberofcols;x++){
table1.getColumnModel().getColumn(x).setCellRenderer( centerRenderer );
}

Here you go:
import javax.swing.*;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.TableModel;
public class JTableUtilities
{
public static void setCellsAlignment(JTable table, int alignment)
{
DefaultTableCellRenderer rightRenderer = new DefaultTableCellRenderer();
rightRenderer.setHorizontalAlignment(alignment);
TableModel tableModel = table.getModel();
for (int columnIndex = 0; columnIndex < tableModel.getColumnCount(); columnIndex++)
{
table.getColumnModel().getColumn(columnIndex).setCellRenderer(rightRenderer);
}
}
}
Usage:
JTableUtilities.setCellsAlignment(table, SwingConstants.CENTER);

I had a similar problem. I wanted to align a single cell depending on the value of another cell. If cell X was NULL, then cell Y should be RIGHT aligned. Else, cell Y should be LEFT aligned.
I found this solution really helpful. It consists on creating a custom Render, extending DefaultTableCellRender.
Here's the code:
public class MyRender extends DefaultTableCellRenderer{
#Override
public Component getTableCellRendererComponent(JTable table,Object value,boolean isSelected,boolean hasFocus,int row,int column){
super.getTableCellRendererComponent (table, value, isSelected, hasFocus, row, column);
MyTableModel mtm = (MyTableModel)table.getModel();
switch(column){
case Y :
if(mla.getValueAt(row,X)!=null)
setHorizontalAlignment(SwingConstants.RIGHT);
else
setHorizontalAlignment(SwingConstants.LEFT);
break;
}
return this;
}
}
After that, just create a new instance of MyRender and set it to column Y, in this case. I do this when I load the information on the table.
MyRender render = new MyRender();
table.getColumnModel().getColumn(Y).setCellRender(render);
Hope it's useful!

Instead of JLabel.CENTER, you can use SwingConstants.CENTER.

((DefaultTableCellRenderer) jTable1.getTableHeader().getDefaultRenderer())
.setHorizontalAlignment(JLabel.CENTER); // header to center
This code header center jtable
DefaultTableCellRenderer rendar = new DefaultTableCellRenderer();
rendar.setHorizontalAlignment(jLabel1.CENTER);
jTable1.getColumnModel().getColumn(0).setCellRenderer(rendar);
this code to column center