FULL PRODUCT VERSION :
java version "1.8.0_131"
Java(TM) SE Runtime Environment (build 1.8.0_131-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.131-b11, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux o 4.4.0-83-generic #106-Ubuntu SMP x86_64 x86_64 x86_64 GNU/Linux


EXTRA RELEVANT SYSTEM CONFIGURATION :
Germany keyboard layout

A DESCRIPTION OF THE PROBLEM :
I can't enter an accented character like à. instead, the application produces an NPE. Other non accented characters work. And also things like §, $, % etc work correctly.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Start the application and enter an accented character, e.g. typing SHIFT + ` +a



EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The accented character appears correctly in the textfield
ACTUAL -
The character does not appear and an NPE is thrown.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at javafx.embed.swing.JFXPanel.sendInputMethodEventToFX(JFXPanel.java:647)
at javafx.embed.swing.JFXPanel.processInputMethodEvent(JFXPanel.java:635)
at java.awt.Component.processEvent(Component.java:6315)
at java.awt.Container.processEvent(Container.java:2236)
at java.awt.Component.dispatchEventImpl(Component.java:4889)
at java.awt.Container.dispatchEventImpl(Container.java:2294)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:90)
at java.awt.EventQueue$4.run(EventQueue.java:731)
at java.awt.EventQueue$4.run(EventQueue.java:729)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)



REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package application;

import javax.swing.JFrame;
import javax.swing.SwingUtilities;

import javafx.application.Platform;
import javafx.embed.swing.JFXPanel;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.TextField;
import javafx.scene.paint.Color;

public class Test {

    private static void initAndShowGUI() {
        // This method is invoked on the EDT thread
        JFrame frame = new JFrame("Swing and JavaFX");
        final JFXPanel fxPanel = new JFXPanel();
        frame.add(fxPanel);
        frame.setSize(300, 200);
        frame.setVisible(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        Platform.runLater(new Runnable() {

            @Override
            public void run() {
                initFX(fxPanel);
            }
        });
    }

    private static void initFX(JFXPanel fxPanel) {
        // This method is invoked on the JavaFX thread
        Scene scene = createScene();
        fxPanel.setScene(scene);
    }

    private static Scene createScene() {
        Group root = new Group();
        Scene scene = new Scene(root, Color.ALICEBLUE);

        TextField tf = new TextField();
       
        root.getChildren().add(tf);

        return (scene);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                initAndShowGUI();
            }
        });
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Type the accented character elsewhere, copy it, and paste it into the field