drawString with Rectangle border

I want to draw string using Graphics with Rectangle border outside the string.

This is what I already do:

public void paint(Graphics g) {
         Graphics2D g2d = (Graphics2D) g;
         FontMetrics fontMetrics = g2d.getFontMetrics();
         String str = "aString Test";
 
         int width = fontMetrics.stringWidth(str);
         int height = fontMetrics.getHeight();
 
         int x = 100;
         int y = 100;
 
         // Draw String
         g2d.drawString(str, x, y);
         // Draw Rectangle Border based on the string length & width
         g2d.drawRect(x - 2, y - height + 2, width + 4, height);
     }
 

My problem is, I want to draw string with new line ("\n") with Rectangle border outside:

This is the code for the new line:

public void paint(Graphics g) {
         Graphics2D g2d = (Graphics2D) g;
         FontMetrics fontMetrics = g2d.getFontMetrics();
         String str = "aString\nTest";
 
         int width = fontMetrics.stringWidth(str);
         int height = fontMetrics.getHeight();
 
         int x = 100;
         int y = 100;
 
         // Drawing string per line
         for (String line : str.split("\n")) {
             g2d.drawString(line, x, y += g.getFontMetrics().getHeight());
         }
     }
 

Can anyone help me for this problem? I appreciate your help & suggestion...

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