junit.extensions.jfcunit.tools.JFCUtilities Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jfcunitex Show documentation
The newest version!
package junit.extensions.jfcunit.tools;

import java.awt.Component;
import java.awt.Dimension;
import java.awt.Toolkit;
import java.awt.Window;

import javax.swing.SwingUtilities;


/**
 * JFCUtilities provides convenience methods for frequently needed GUI programming operations.
 *
 * @author Vijay Aravamudhan : ThoughtWorks Inc.
 */
public final class JFCUtilities {
    /**
     * Hide the constructor.
     */
    private JFCUtilities() {
    }

    /**
     * A utility method to center a Window.
     *
     * @param win    The Window to be centered.
     */
    public static void center(final Window win) {
        center(win, null);
    }

    /**
     * A utility method to center a Window with respect to its parent Window.
     *
     * @param win    The Window to be centered.
     * @param comp   The parent Component of the above Window.
     */
    public static void center(final Window win, final Component comp) {
        Window parentWin = null;

        if (comp != null) {
            parentWin = SwingUtilities.windowForComponent(comp);
        }

        Dimension winSize    = win.getSize();
        Dimension parentSize = Toolkit.getDefaultToolkit().getScreenSize();
        int       startX     = 0;
        int       startY     = 0;

        if (parentWin != null) {
            startX         = parentWin.getLocation().x;
            startY         = parentWin.getLocation().y;
            parentSize     = parentWin.getSize();
        }

        // If child window is larger than parent window, startX or startY could be negative
        // If the calculated value is negative, use 0 instead
        win.setLocation(
            Math.max(0, startX + ((parentSize.width - winSize.width) / 2)),
            Math.max(0, startY + ((parentSize.height - winSize.height) / 2)));
    }

    /**
     * A utility method to find a Component in the component's parent hierarchy which is of the type
     * specified.
     *
     * @param comp    The Component whose hierarchy has to be searched for the JViewport.
     * @param clazz   The type of the required parent
     * @return    The parent that contains the component or one of its parents, null if not found.
     */
    public static Component findComponentInHierarchy(final Component comp,
        final Class clazz) {
        if (comp == null) {
            return null;
        }

        Component parent = comp.getParent();

        while ((parent != null) && !(clazz.isInstance(parent))) {
            parent = parent.getParent();
        }

        if (clazz.isInstance(parent)) {
            return parent;
        }

        return null;
    }
}