Is it possible to line up swing components? The components are in separate panels which both use flow layout. These two panels are in another panel which is using a grid layout.

As you can see there is a subtle difference and I find it annoying. I know that all of the jlabels [the rectangles in blue/purple all have the same size, so i think it might be because of the '+' and '*', but I'm not sure because the left sides of the first two boxes aren't lined up.

the panels

JPanel panel2 = new JPanel(new GridLayout(4, 1));
JPanel panel2a = new JPanel(new FlowLayout());
JPanel panel2b = new JPanel(new FlowLayout());

the first two rectangles (purple)

add1 = new JLabel("", JLabel.CENTER);
add1.setTransferHandler(new TransferHandler("text"));
add1.setBorder(b2);
add2 = new JLabel("", JLabel.CENTER);
add2.setTransferHandler(new TransferHandler("text"));
add2.setBorder(b2);

the two blue rectangles

textFieldA = new JTextField();
textFieldA.setHorizontalAlignment(JTextField.CENTER);
textFieldA.setEditable(false);
textFieldA.setBorder(new LineBorder(Color.blue));
textFieldM = new JTextField();
textFieldM.setHorizontalAlignment(JTextField.CENTER);
textFieldM.setEditable(false);
textFieldM.setBorder(new LineBorder(Color.blue));

the + and *

opA = new JLabel("+", JLabel.CENTER);
opS = new JLabel("*", JLabel.CENTER);

Showing that the rectangles are the same size

Dimension d = card1.getPreferredSize(); 
int width = d.width + 100;
int height = d.height + 50;

add1.setPreferredSize(new Dimension(width, height));
add2.setPreferredSize(new Dimension(width, height));
mult1.setPreferredSize(new Dimension(width, height));
mult2.setPreferredSize(new Dimension(width, height));

textFieldA.setPreferredSize(new Dimension(width, height));
textFieldM.setPreferredSize(new Dimension(width, height));

Adding to the panels

panel2a.add(add1);
panel2a.add(opA);
panel2a.add(add2);
panel2a.add(enterA);
panel2a.add(textFieldA);
panel2c.add(mult1);
panel2c.add(opM);
panel2c.add(mult2);
panel2c.add(enterM);
panel2c.add(textFieldM);
panel2.add(panel2a);
panel2.add(panel2c);