Changing the color of the lines between JTable header cells

Main.java:

import javax.swing.plaf.basic.*;
import javax.swing.border.*;
import javax.swing.*;
import javax.swing.table.*;
import java.awt.*;
import java.awt.event.*;
 
public class Main extends JFrame 
{
   public Main() {
      String[] header = {"column #1","column #2","column #3", "column #4"};
      String[][] data = {{"1","2","3","4"},
                         {"5","6","7","8"}};
 
      JTable table = new JTable(data, header);
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      getContentPane().add(new JScrollPane(table));
 
      MyHeaderRenderer renderer = new MyHeaderRenderer();
      System.out.println(table.getTableHeader().getDefaultRenderer());
      table.getTableHeader().setDefaultRenderer(renderer);
       
      setSize(300,200);
   } 

 
   public static void main( String args[] ) { 
      Main main = new Main();
      main.setVisible(true);
   }
}
 
class MyHeaderRenderer extends DefaultTableCellRenderer 
{
   private static LineBorder border = new LeftColorLineBorder((Color) UIManager.get("Button.focus"));
 
   public java.awt.Component getTableCellRendererComponent(JTable table, Object value,
                                 boolean selected, boolean focus, int row, int col) {
      Component c = super.getTableCellRendererComponent(table, value, selected, focus, row, col);
 


      setHorizontalAlignment(JLabel.CENTER);
      setBorder(border);
      return c;
   }
}
 
class LeftColorLineBorder extends LineBorder
{
   public LeftColorLineBorder(Color color) {
      super(color, 1, false);
   }
 
   public LeftColorLineBorder(Color color, int thickness) {
      super(color, thickness, false);
   }
 
   public LeftColorLineBorder(Color color, int thickness, boolean roundedCorners) {
      super(color, thickness, roundedCorners);
   }
   
   public void paintBorder(Component c, Graphics g, int x, int y, int width, int height) {
      super.paintBorder(c, g, x, y, width, height);
      g.setColor(Color.black);
      g.fillRect(x, y, x+4, y+height);
      g.fillRect(x+width-4, y, x+width, y+height);
   }
}