Java

if the fedora system got hanged , it mean, once the system got login, then after few min, it may got hang, if it hanged and it doesn't allow you to do any operation mean,  you have to reboot the system with by checking the kernal or root system files. to do that,  give the following command  $ sudo touch forcefsck  or  $ sudo touch etc forcefsck then reboot you system.

use this link you will get samples for the concept you searching.. http://www.exampledepot.com/egs/javax.swing.table/RemoveRow.html

if the table is create with DefaultTableModel, then the following code can be used. i have used and tested... private void removeTable() { if(reportModel.getRowCount() 0) { reportModel.removeRow(0); } }