test/jdk/java/awt/Focus/ComponentLostFocusTest.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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 * questions.
 */

/*
 * @test
 * @bug 4982943
 * @key headful
 * @summary focus lost in text fields or text areas, unable to enter characters from keyboard
 * @run main ComponentLostFocusTest
 */

import java.awt.Dialog;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.KeyboardFocusManager;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.TextField;
import java.awt.Toolkit;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.awt.event.InputEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.File;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

import javax.imageio.ImageIO;

public class ComponentLostFocusTest {

    static Frame frame;
    static TextField tf;
    static Robot r;
    static Dialog dialog = null;
    static volatile Point loc;
    static volatile int width;
    static volatile int top;
    static final CountDownLatch focusGainedLatch = new CountDownLatch(1);

    private static void createTestUI() {

        dialog = new Dialog(frame, "Dialog", true);

        frame = new Frame("ComponentLostFocusTest Frame");
        frame.setLayout(new FlowLayout());
        frame.addWindowFocusListener(new WindowAdapter() {
            public void windowGainedFocus(WindowEvent e) {
                System.out.println("Frame gained focus: "+e);
            }
        });
        tf = new TextField("Text Field");
        frame.add(tf);
        frame.setSize(400,300);
        frame.setVisible(true);
        frame.setLocationRelativeTo(null);
        frame.validate();
    }

    public static void doTest() {
        System.out.println("dialog.setVisible.... ");
        new Thread(() -> dialog.setVisible(true)).start();

        // The bug is that this construction leads to the redundant xRequestFocus
        // By the way, the requestFocusInWindow() works fine before the fix
        System.out.println("requesting.... ");
        frame.requestFocus();

        r.delay(1000);

        // Returning the focus to the initial frame will work correctly after the fix
        System.out.println("disposing.... ");
        dialog.dispose();

        r.delay(1000);

        // We want to track the GAIN_FOCUS from this time
        tf.addFocusListener(new FocusAdapter() {
            public void focusGained(FocusEvent e) {
                System.out.println("TextField gained focus: " + e);
                focusGainedLatch.countDown();
            }
        });

    }

    private static void doRequestFocusToTextField() {
        // do activation using press title
        r.mouseMove(loc.x + width / 2, loc.y + top / 2);
        r.waitForIdle();
        r.mousePress(InputEvent.BUTTON1_DOWN_MASK);
        r.mouseRelease(InputEvent.BUTTON1_DOWN_MASK);
        r.waitForIdle();

        // request focus to the text field
        tf.requestFocus();
    }

    private static void captureScreen() {
        try {
            final Rectangle screenBounds = new Rectangle(
                    Toolkit.getDefaultToolkit().getScreenSize());
            ImageIO.write(r.createScreenCapture(screenBounds),
                    "png", new File("ComponentLostFocusTest.png"));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static final void main(String args[]) throws Exception {
        r = new Robot();
        r.setAutoDelay(100);

        EventQueue.invokeAndWait(() -> createTestUI());
        r.waitForIdle();
        r.delay(1000);
        try {
            EventQueue.invokeAndWait(() -> {
                doTest();
                loc = frame.getLocationOnScreen();
                width = frame.getWidth();
                top = frame.getInsets().top;
            });
            doRequestFocusToTextField();

            System.out.println("Focused window: " +
                KeyboardFocusManager.getCurrentKeyboardFocusManager().
                                     getFocusedWindow());
            System.out.println("Focus owner: " +
                KeyboardFocusManager.getCurrentKeyboardFocusManager().
                                     getFocusOwner());
            if (!focusGainedLatch.await(5, TimeUnit.SECONDS)) {
                captureScreen();
                throw new RuntimeException("Waited too long, " +
                        "TextField got no focus! Test failed.");
            }
        } finally {
            EventQueue.invokeAndWait(() -> {
                if (frame != null) {
                    frame.dispose();
                }
            });
        }
    }
}