JFrame f=new JFrame();
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();f.setBounds(0,0,screenSize.width,screenSize.height);
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();f.setBounds(0,0,screenSize.width,screenSize.height);
JFrame f=new JFrame("aaa");
f.setVisible(true);
f.setExtendedState(Frame.MAXIMIZE_BOTH);