JTable cell renderer skips Boolean column

Question

Below is a picture of my JTable. My problem is that the blue background every other row isn't present in the 4th column. My table model and cell renderer are also below.

Table model:

public class MyTableModel extends DefaultTableModel {
    public int getColumnCount() {
        return columnNames.length;
    }

    public String getColumnName(int column) {
        return columnNames[column];
    }

    public int getRowCount() {
        return data.length;
    }

    public Object getValueAt(int row, int column) {
        return data[row][column];
    }

    public Class getColumnClass(int column) {
        return (getValueAt(0, column).getClass());
    }

    public void setValueAt(Object value, int row, int column) {
        data[row][column] = value;
    }

    public boolean isCellEditable(int row, int column) {
        return (column == 3);
    }
    }

Cell Renderer:

    private class CalendarRenderer extends DefaultTableCellRenderer {
    private static final long serialVersionUID = 1L;

    public Component getTableCellRendererComponent(JTable table, Object value, boolean selected, boolean focused, int row, int column) {
        super.getTableCellRendererComponent(table, value, selected, focused, row, column);

        setBackground(new Color(0xFFFFFF));

        if (row % 2 == 1) {
        setBackground(new Color(0xE8F2FE)); //light blue
        }

        setBorder(null);
        setForeground(Color.black);
        return this;
    }
    }

Answer 1

The "default" cell renderer for Boolean is a check box. If you want to change the way that this cell gets rendered, you're going to have to supply your own TableCellRenderer that implements your own logic.

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;
import javax.swing.table.AbstractTableModel;
import javax.swing.table.TableCellRenderer;

public class TestTableCellRenderer {

    public static void main(String[] args) {
        new TestTableCellRenderer();
    }

    public TestTableCellRenderer() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                }

                JTable table = new JTable();
                table.setModel(new TableModel());
                table.setDefaultRenderer(Boolean.class, new BooleanCellRenderer());

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new JScrollPane(table));
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TableModel extends AbstractTableModel {

        private List<Boolean> values = new ArrayList<>(25);

        public TableModel() {
            for (int index = 0; index < 25; index++) {
                values.add((((int) Math.round(Math.random() * 1)) == 0 ? false : true));
            }
        }

        @Override
        public int getRowCount() {
            return values.size();
        }

        @Override
        public int getColumnCount() {
            return 1;
        }

        @Override
        public Object getValueAt(int rowIndex, int columnIndex) {
            return values.get(rowIndex);
        }

        @Override
        public Class<?> getColumnClass(int columnIndex) {
            return Boolean.class;
        }
    }

    public static class BooleanCellRenderer extends JCheckBox implements TableCellRenderer {

        private static final Border noFocusBorder = new EmptyBorder(1, 1, 1, 1);

        public BooleanCellRenderer() {
            setLayout(new GridBagLayout());
            setMargin(new Insets(0, 0, 0, 0));
            setHorizontalAlignment(JLabel.CENTER);
        }

        @Override
        public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
            if (value instanceof Boolean) {
                setSelected((Boolean) value);
            }
            if (!isSelected) {
                setBackground(new Color(0xFFFFFF));
                if (row % 2 == 1) {
                    setBackground(new Color(0xE8F2FE)); //light blue
                }
                setForeground(Color.black);
            } else {
                setForeground(table.getSelectionForeground());
                setBackground(table.getSelectionBackground());
            }
            if (hasFocus) {
                setBorder(UIManager.getBorder("Table.focusCellHighlightBorder"));
            } else {
                setBorder(noFocusBorder);
            }
            return this;
        }
    }
}

Answer 2

See Table Row Rendering for a solution that doesn't require you to keep creating custom renderers every time you have columns with different data.

JTable table = new JTable( model )
{
    public Component prepareRenderer(TableCellRenderer renderer, int row, int column)
    {
        Component c = super.prepareRenderer(renderer, row, column);

        //  Alternate row color

        if (!isRowSelected(row))
            c.setBackground(row % 2 == 0 ? getBackground() : Color.LIGHT_GRAY);

        return c;
    }
};