Need Help To Connect XML as backend in Java-Swing

Seat arrangment swing screenshot

I made XML program to connect to swing like this.

<?xml version="1.0" encoding="iso-8859-1"?>
<BUISNESS-CLASS>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME>Selva</NAME>
<SEATNO>B1</SEATNO>
<OCCUPIED>N</OCCUPIED>
<OCCUPIEDBY>REFID00000</OCCUPIEDBY>
<KIND>A</KIND>
</PERSON>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME>Ganesh</NAME>
<SEATNO>B2</SEATNO>
<OCCUPIED>Y</OCCUPIED>
<OCCUPIEDBY>REFID00001</OCCUPIEDBY>
<KIND>A</KIND>
</PERSON>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME>Nellai</NAME>
<SEATNO>B3</SEATNO>
<OCCUPIED>N</OCCUPIED>
<OCCUPIEDBY>REFID00002</OCCUPIEDBY>
<KIND>A</KIND>
</PERSON>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME>Samurai</NAME>
<SEATNO>B4</SEATNO>
<OCCUPIED>Y</OCCUPIED>
<OCCUPIEDBY>REFID00003</OCCUPIEDBY>
<KIND>I</KIND>
</PERSON>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME>Raja</NAME>
<SEATNO>B5</SEATNO>
<OCCUPIED>Y</OCCUPIED>
<OCCUPIEDBY>REFID00004</OCCUPIEDBY>
<KIND>I</KIND>
</PERSON>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME>Mano</NAME>
<SEATNO>B6</SEATNO>
<OCCUPIED>Y</OCCUPIED>
<OCCUPIEDBY>REFID00005</OCCUPIEDBY>
<KIND>I</KIND>
</PERSON>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME>Raju</NAME>
<SEATNO>B7</SEATNO>
<OCCUPIED>Y</OCCUPIED>
<OCCUPIEDBY>REFID00006</OCCUPIEDBY>
<KIND>I</KIND>
</PERSON>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME>Ram</NAME>
<SEATNO>B8</SEATNO>
<OCCUPIED>Y</OCCUPIED>
<OCCUPIEDBY>REFID00007</OCCUPIEDBY>
<KIND>A</KIND>
</PERSON>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME>Shree</NAME>
<SEATNO>B9</SEATNO>
<OCCUPIED>N</OCCUPIED>
<OCCUPIEDBY>REFID00008</OCCUPIEDBY>
<KIND>A</KIND>
</PERSON>
<PERSON>
<CATEGORY>BUSINESS</CATEGORY>
<NAME></NAME>
<SEATNO>B10</SEATNO>
<OCCUPIED>N</OCCUPIED>
<OCCUPIEDBY>REFID00009</OCCUPIEDBY>
<KIND>A</KIND>
</PERSON>
</BUISNESS-CLASS>

now my problem is if i click the B1 label it need to change as(occupied-grey colour) and data changed to Y...but it did nt do it..

i cant understand how to do this.....

thanks....