test/jdk/java/awt/event/MouseEvent/DragToLightweightTest.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/*
 * @test
 * @bug 4417964
 * @summary tests that drag events continue to arrive to heavyweight
 *          when the mouse is moved to lightweight while dragging.
 * @key headful
 * @library /lib/client /java/awt/regtesthelpers
 * @build ExtendedRobot Util
 * @run main DragToLightweightTest
*/

import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.HeadlessException;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

import test.java.awt.regtesthelpers.Util;

public class DragToLightweightTest {

    private static final CountDownLatch latch = new CountDownLatch(1);
    private static volatile MouseTest mouseTest;

    public static void main(String[] args) throws Exception {

        EventQueue.invokeAndWait(() -> mouseTest = new MouseTest());

        try {
            test();
        } finally {
            EventQueue.invokeAndWait(() -> {
                if (mouseTest != null) {
                    mouseTest.dispose();
                }
            });
        }
    }

    private static void test() throws Exception {
        ExtendedRobot robot = new ExtendedRobot();
        robot.waitForIdle();
        robot.delay(500);

        Rectangle componentBounds = mouseTest.getLightweightComponentBounds();

        robot.dragAndDrop(
                componentBounds.x + componentBounds.width / 2, componentBounds.y + componentBounds.height + 30,
                componentBounds.x + componentBounds.width / 2, componentBounds.y + 2 * componentBounds.height / 3
        );

        if (!latch.await(5, TimeUnit.SECONDS)) {
            throw new RuntimeException("The test failed: no mouse release event received");
        }

        System.out.println("Mouse release event received, the test PASSED");
    }

    private static class MouseTest extends Frame {

        final Foo foo;

        public MouseTest() throws HeadlessException {
            super("DragToLightweightTest");

            setLayout(new FlowLayout());

            addMouseListener(new MouseAdapter() {
                @Override
                public void mouseReleased(MouseEvent e) {
                    System.out.println("mouseReleased");
                    latch.countDown();
                }
            });

            // Create a Component that will be a child of the Frame and add
            // a MouseListener to it.
            foo = new Foo();
            foo.setBackground(Color.red);

            System.out.println(foo.getPreferredSize());
            foo.setPreferredSize(new Dimension(350, 200));
            System.out.println(foo.getPreferredSize());

            foo.addMouseListener(new DummyAdapter());

            add(foo);

            setSize(400, 400);
            setLocationRelativeTo(null);
            setVisible(true);
        }

        public Rectangle getLightweightComponentBounds() throws Exception {
            return Util.invokeOnEDT(() -> {
                Point locationOnScreen = foo.getLocationOnScreen();
                Dimension size = foo.getSize();
                return new Rectangle(locationOnScreen.x, locationOnScreen.y, size.width, size.height);
            });
        }

        private static class Foo extends Container {
            public void paint(Graphics g) {
                g.setColor(getBackground());
                g.fillRect(0, 0, getWidth(), getHeight());
                g.setColor(Color.white);
                g.drawString(getBounds().toString(), 5, 20);
                super.paint(g);
            }
        }

        private static class DummyAdapter extends MouseAdapter {}
    }
}