FULL PRODUCT VERSION :




ADDITIONAL OS VERSION INFORMATION :
Mac OS X - 10.12.3

A DESCRIPTION OF THE PROBLEM :
Whilst in a JScrollPane,  after scrolling a "two finger tap" to simulate a right click moves the JViewport is moved then the right click is performed. 

For larger application this makes right clicking on items in a Scrollable JViewport nonfunctional (Can be done with a Ctrl+Click) .







REGRESSION.  Last worked in version 8u111

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Using: https://docs.oracle.com/javase/tutorial/displayCode.html?code=https://docs.oracle.com/javase/tutorial/uiswing/examples/components/ScrollDemo2Project/src/components/ScrollDemo2.java

First create an abundance of circles in the application, So that the application expands and the JScrollPane is smaller than the JViewport. 

Scroll across the JViewport then "Tap" (make sure not to click as this will remove the circles) with two fingers anywhere on the JViewport - notice the movement of the JViewport. This movement is larger in other applications.  

See Video:
http://uppit.com/g8li3gvmal7c

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The expected result is to perform a right click with no movement.
ACTUAL -
A right click was performed, delayed by the movement in the JViewport. 

See Video: 
http://uppit.com/g8li3gvmal7c

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
/*
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 *
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 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
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 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
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 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
package components;
 
/*
 * This code is based on an example provided by John Vella,
 * a tutorial reader.
 */
 
import javax.swing.*;
import javax.swing.event.MouseInputAdapter;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
 
/* ScrollDemo2.java requires no other files. */
public class ScrollDemo2 extends JPanel
                         implements MouseListener {
    private Dimension area; //indicates area taken up by graphics
    private Vector<Rectangle> circles; //coordinates used to draw graphics
    private JPanel drawingPane;
 
    private final Color colors[] = {
        Color.red, Color.blue, Color.green, Color.orange,
        Color.cyan, Color.magenta, Color.darkGray, Color.yellow};
    private final int color_n = colors.length;
 
    public ScrollDemo2() {
        super(new BorderLayout());
 
        area = new Dimension(0,0);
        circles = new Vector<Rectangle>();
 
        //Set up the instructions.
        JLabel instructionsLeft = new JLabel(
                        "Click left mouse button to place a circle.");
        JLabel instructionsRight = new JLabel(
                        "Click right mouse button to clear drawing area.");
        JPanel instructionPanel = new JPanel(new GridLayout(0,1));
        instructionPanel.setFocusable(true);
        instructionPanel.add(instructionsLeft);
        instructionPanel.add(instructionsRight);
 
        //Set up the drawing area.
        drawingPane = new DrawingPane();
        drawingPane.setBackground(Color.white);
        drawingPane.addMouseListener(this);
 
        //Put the drawing area in a scroll pane.
        JScrollPane scroller = new JScrollPane(drawingPane);
        scroller.setPreferredSize(new Dimension(200,200));
 
        //Lay out this demo.
        add(instructionPanel, BorderLayout.PAGE_START);
        add(scroller, BorderLayout.CENTER);
    }
 
    /** The component inside the scroll pane. */
    public class DrawingPane extends JPanel {
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
 
            Rectangle rect;
            for (int i = 0; i < circles.size(); i++) {
                rect = circles.elementAt(i);
                g.setColor(colors[(i % color_n)]);
                g.fillOval(rect.x, rect.y, rect.width, rect.height);
            }
        }
    }
 
    //Handle mouse events.
    public void mouseReleased(MouseEvent e) {
        final int W = 100;
        final int H = 100;
        boolean changed = false;
        if (SwingUtilities.isRightMouseButton(e)) {
            //This will clear the graphic objects.
            circles.removeAllElements();
            area.width=0;
            area.height=0;
            changed = true;
        } else {
            int x = e.getX() - W/2;
            int y = e.getY() - H/2;
            if (x < 0) x = 0;
            if (y < 0) y = 0;
            Rectangle rect = new Rectangle(x, y, W, H);
            circles.addElement(rect);
            drawingPane.scrollRectToVisible(rect);
 
            int this_width = (x + W + 2);
            if (this_width > area.width) {
                area.width = this_width; changed=true;
            }
 
            int this_height = (y + H + 2);
            if (this_height > area.height) {
                area.height = this_height; changed=true;
            }
        }
        if (changed) {
            //Update client's preferred size because
            //the area taken up by the graphics has
            //gotten larger or smaller (if cleared).
            drawingPane.setPreferredSize(area);
 
            //Let the scroll pane know to update itself
            //and its scrollbars.
            drawingPane.revalidate();
        }
        drawingPane.repaint();
    }
    public void mouseClicked(MouseEvent e){}
    public void mouseEntered(MouseEvent e){}
    public void mouseExited(MouseEvent e){}
    public void mousePressed(MouseEvent e){}
 
    /**
     * Create the GUI and show it.  For thread safety,
     * this method should be invoked from the
     * event-dispatching thread.
     */
    private static void createAndShowGUI() {
        //Create and set up the window.
        JFrame frame = new JFrame("ScrollDemo2");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
        //Create and set up the content pane.
        JComponent newContentPane = new ScrollDemo2();
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.setContentPane(newContentPane);
 
        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }
 
    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}
---------- END SOURCE ----------