JPanel Padding in Java
Set an EmptyBorder around your JPanel.
Example:
JPanel p =new JPanel();
p.setBorder(new EmptyBorder(10, 10, 10, 10));
When you need padding inside the JPanel generally you add padding with the layout manager you are using. There are cases that you can just expand the border of the JPanel.
I will suppose your JPanel contains JTextField, for the sake of the demo.
Those components provides JTextComponent#setMargin() method which seems to be what you're looking for.
If you're looking for an empty border of any size around your text, well, use EmptyBorder