FULL PRODUCT VERSION :
java version "1.8.0_60"
Java(TM) SE Runtime Environment (build 1.8.0_60-b27)
Java HotSpot(TM) 64-Bit Server VM (build 25.60-b23, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
Focus switches from the focussed component to two components further in the focus chain when a dialog is opened and closed before it received focus itself.

It seems to go wrong because
java.awt.Component#7663: A component registers itself as mostRecentFocusOwner
java.awt.Component#7703: The component requests focus (this fails in the reproduction)

Is done in combination with:
java.awt.DefaultKeyboardFocusManager:doRestoreFocus(Window, Component, Boolean): trying to focus the MostRecentFocusOwner and then the next one

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1) Run the attached source
2) Press Enter in any of the textfields
A dialog opens and closes immediately.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The focused component should still be the textfield that was focused when pressing Enter.
ACTUAL -
The focus switches from the original field to the field that is 2 components further in the focus chain.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.WindowConstants;

public class FocusBug extends JFrame implements ActionListener
{
  private final SimpleDialog mDialog = new SimpleDialog();

  public static void main(String[] args)
  {
    FocusBug tfs = new FocusBug();
    tfs.setVisible(true);
  }

  public FocusBug()
  {
    setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);

    Container c = getContentPane();
    c.setLayout(new FlowLayout());
    for (int i = 0; i < 10; i++)
    {
      JTextField tf = new JTextField(10);
      c.add(tf);
      tf.addActionListener(this);
    }
    pack();
  }

  @Override
  public void actionPerformed(ActionEvent e)
  {
    mDialog.showQuickly();
  }

  private static class SimpleDialog extends JDialog
  {
    public void showQuickly()
    {
      setVisible(true);
      setVisible(false);
    }
  }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
It is possible to add a WindowFocusListener to the dialog that waits until the setVisible(false) is called _and_ it has received focus. If one of the two is called it should wait before actually calling super.setVisible(false).