怎么在jtable的列前面加单选框附上代码和注释

对于您的问题，在jtable的列前面加单选框可以通过自定义TableCellRenderer和TableCellEditor来实现。下面是一个例子：

import java.awt.Component;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.AbstractCellEditor;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.UIManager;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableCellEditor;
import javax.swing.table.TableCellRenderer;

public class JTableExample {

    public static void main(String[] args) {
        JFrame frame = new JFrame("JTable Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        Object[] columnNames = {"Name", "Age", "Gender", "Select"};
        Object[][] rowData = {
            {"John Doe", 30, "Male", false},
            {"Jane Doe", 25, "Female", false},
            {"Bob Smith", 40, "Male", false},
            {"Alice Jones", 35, "Female", false}
        };
        DefaultTableModel model = new DefaultTableModel(rowData, columnNames);
        JTable table = new JTable(model) {
            @Override
            public Class getColumnClass(int column) {
                return getValueAt(0, column).getClass();
            }
        };
        table.getColumnModel().getColumn(3).setCellRenderer(new RadioButtonRenderer());
        table.getColumnModel().getColumn(3).setCellEditor(new RadioButtonEditor(new JCheckBox()));
        JScrollPane scrollPane = new JScrollPane(table);
        frame.add(scrollPane);
        frame.pack();
        frame.setVisible(true);
    }

    static class RadioButtonRenderer extends JCheckBox implements TableCellRenderer {

        public RadioButtonRenderer() {
            setOpaque(true);
        }

        @Override
        public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
            if (value != null) {
                setSelected((Boolean) value);
            }
            return this;
        }
    }

    static class RadioButtonEditor extends AbstractCellEditor implements TableCellEditor, ActionListener {

        private JCheckBox checkBox;

        public RadioButtonEditor(JCheckBox checkBox) {
            this.checkBox = checkBox;
            checkBox.addActionListener(this);
        }

        @Override
        public Object getCellEditorValue() {
            return checkBox.isSelected();
        }

        @Override
        public Component getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int row, int column) {
            if (value != null) {
                checkBox.setSelected((Boolean) value);
            }
            return checkBox;
        }

        @Override
        public void actionPerformed(ActionEvent e) {
            fireEditingStopped();
        }
    }
}

这个例子中，我们创建了一张包含"Name"、"Age"、"Gender"、"Select"这四列的表格，并给"Select"这一列加上了单选框，可以让用户在表格中选择一行数据。可以根据需要修改列名和数据，然后添加到您的项目中。