/*
 * -----------------------------------------------------------------------------
 * (c) Copyright IBM Corp. 2003 All rights reserved. The sample program(s)
 * is/are owned by International Business Machines Corporation or one of its
 * subsidiaries ("IBM") and is/are copyrighted and licensed, not sold. You may
 * copy, modify, and distribute this/these sample program(s) in any form without
 * payment to IBM, for any purpose including developing, using, marketing or
 * distributing programs that include or are derivative works of the sample
 * program(s). The sample program(s) is/are provided to you on an "AS IS" basis,
 * without warranty of any kind. IBM HEREBY EXPRESSLY DISCLAIMS ALL WARRANTIES,
 * EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Some
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 * Each copy of any portion of this/these sample program(s) or any derivative
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package swing2swt.layout;

import java.awt.Dimension;

import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Layout;

/**
 * Superclass for all the AWT layouts ported to SWT.
 * 
 * @author Yannick Saillet
 */
public abstract class AWTLayout extends Layout {
    /**
     * Key under which an eventual preferred size (set width setPreferredSize)
     * is stored as a user data in the SWT control.
     */
    public final static String KEY_PREFERRED_SIZE = "preferredSize";

    /**
     * Gets the preferred size of a component. If a preferred size has been set
     * width setPreferredSize, returns it, otherwise returns the component
     * computed preferred size.
     */
    protected Point getPreferredSize(Control control, int wHint, int hHint, boolean changed) {
        // check if a preferred size was set on the control width
        // SWTComponent.setPreferredSize(Dimension)
        Dimension d = (Dimension)control.getData(KEY_PREFERRED_SIZE);
        if (d != null)
            return new Point(d.width, d.height);
        return control.computeSize(wHint, hHint, changed);
    }
}