Here you can find the source of getFrameSize(Component c)
public static Dimension getFrameSize(Component c)
//package com.java2s; /*// www .j a va 2 s .c om * DataViewerUtilities.java 2/6/13 1:04 PM * * Copyright (C) 2012-2013 Nick Ma * * 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. */ import java.awt.*; import javax.swing.*; public class Main { public static Dimension getFrameSize(Component c) { Container parent = getRootContainer(c); if (parent != null) { return parent.getSize(); } return Toolkit.getDefaultToolkit().getScreenSize(); } public static Container getRootContainer(Component c) { if (c != null) { Container parent = c.getParent(); while ((parent != null) && !(parent instanceof JPopupMenu) && !(parent instanceof JInternalFrame) && !(parent instanceof Window) && (parent.getParent() != null)) { parent = parent.getParent(); } return parent; } return null; } }