i don't know how to hide a close/minimize button in JFrame, but anyway u can
disable it in ur WindowListener method
use myFrame.setResizable(false);

otherwise use

JDialog jdlgTemp = new JDialog();
jdlgTemp.setResizable(false);
jdlgTemp.setDefaultCloseOperation(JDialog.DO_NOTHING_ON_CLOSE);
jdlgTemp.show();