JTable table = new JTable();
    
    // Add data here
    
    // Show both horizontal and vertical grid lines (the default)
    table.setShowGrid(true);
    
    // Don't show any grid lines
    table.setShowGrid(false);
    
    // Show only vertical grid lines
    table.setShowGrid(false);
    table.setShowVerticalLines(true);
    
    // Show only horizontal grid lines
    table.setShowGrid(false);
    table.setShowHorizontalLines(true);
    
    // Set the grid color
    table.setGridColor(Color.red);