Java rounded corner bug

Question

I'm working on a GUI in Java, and I'm trying to give rounded corners to my borders.

JPanel recentProjectsPanel = new JPanel();
    recentProjectsPanel.setLayout(new BorderLayout());
    recentProjectsPanel.setBackground(Color.red);
    recentProjectsPanel.setBorder(new LineBorder(Color.green, 15, true));

This is the output I get (don't mind the colors):

Why do I get these red stripes in the corners? Any way to fix this?

Answer 1

You might use a variant of the TextBubbleBorder instead.

Answer 2

Have a look at this

Java - rounded corner panel with compositing in paintComponent

this has much information regarding same.