Here you can find the source of getDefaultDeviceScreenSize()
public static Dimension getDefaultDeviceScreenSize()
//package com.java2s; /*/*from w w w . j a v a 2 s . c o m*/ * GUIUtils.java * * Copyright (C) 2002-2015 Takis Diakoumis * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 3 * of the License, or any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. * */ import java.awt.Dimension; import java.awt.GraphicsDevice; import java.awt.GraphicsEnvironment; public class Main { public static Dimension getDefaultDeviceScreenSize() { GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment(); GraphicsDevice gs = ge.getScreenDevices()[0]; Dimension screenSize = gs.getDefaultConfiguration().getBounds().getSize(); return screenSize; } }