Also affects JDK 7

In the provided application there are 2 buttons. One with the label "Open Secondary Stage" so simply do the following:


     -> 1º press that button "Open Secondary Stage" and without release drag over the main stage and then release.
     -> 2º press the button in the secondary stage
     -> 3º press on any point in the area of the main stage and a exception "Too many touch points detected will be thrown" and the JVM will fall in an irreversible state


Not to mention, that in a complex applications not in simple demos, it is very easy to fall in this state....

Java Application below:


package application;

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.input.TouchEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.stage.Modality;
import javafx.stage.Stage;
import javafx.stage.StageStyle;

public class Main extends Application {
Stage secondaryStage;
Stage primaryStage;

@Override
public void start(Stage primaryStage) {
try {
this.primaryStage = primaryStage;
BorderPane root = new BorderPane();

Button openDialog = new Button("OPEN SECONDARY STAGE");

openDialog.setOnTouchPressed(new EventHandler<TouchEvent>() {

@Override
public void handle(TouchEvent event) {
System.out.println("TOUCH PRESS");
openSecondarySTage();
if(secondaryStage!=null && secondaryStage.getScene()!=null) {
if(event.getTouchPoint().getGrabbed()!=secondaryStage.getScene()) {
event.getTouchPoint().grab(secondaryStage.getScene());
System.out.println("Grabbed TP: "+event.getTouchPoint().getId()+" by "+event.getTouchPoint().getGrabbed());
}
}
}

});
Button closeDialog = new Button("CLOSE SECONDARY STAGE");

closeDialog.onActionProperty().set(new EventHandler<ActionEvent>() {

@Override
public void handle(ActionEvent event) {
System.out.println("closing secondary from prim button");
closeSecondaryStage();
}

});
Scene scene = new Scene(root, 400, 400);

scene.addEventHandler(TouchEvent.TOUCH_MOVED,
new EventHandler<TouchEvent>() {

@Override
public void handle(TouchEvent event) {
System.out
.println("TOUCH EVENT DETECTED BY PRIMARY STAGE: "
+ event);
}

});
scene.getStylesheets().add(
getClass().getResource("application.css").toExternalForm());
primaryStage.setScene(scene);

HBox centerPane = new HBox();
centerPane.getChildren().add(openDialog);
centerPane.getChildren().add(closeDialog);
root.setCenter(centerPane);
primaryStage.show();
} catch (Exception e) {
e.printStackTrace();
}
}

private void openSecondarySTage() {
if(secondaryStage!=null && secondaryStage.isShowing()) {
secondaryStage.toFront();
return;
}
System.out.println("OPENING SECONDARY STAGE");

BorderPane root = new BorderPane();
secondaryStage = new Stage(StageStyle.UTILITY) ;
secondaryStage.initModality(Modality.APPLICATION_MODAL);

secondaryStage.initOwner(primaryStage);
Scene scn = new Scene(root, 200, 200);
scn.addEventHandler(TouchEvent.TOUCH_MOVED,
new EventHandler<TouchEvent>() {

@Override
public void handle(TouchEvent event) {
System.out
.println("SECONDARY STAGE TOUCHED: "
+ event);
}

});
secondaryStage.setScene(scn);

Button closeOnSec = new Button("CLOSE SECONDARY STAGE");


closeOnSec.setOnAction(new EventHandler<ActionEvent>() {

@Override
public void handle(ActionEvent event) {
System.out.println("Closing Sec from Sec ");
closeSecondaryStage();
}

});
root.setCenter(closeOnSec);
secondaryStage.show();
secondaryStage.toFront();
secondaryStage.setX(primaryStage.getX()+primaryStage.getWidth()/2);
secondaryStage.setY(primaryStage.getY()+primaryStage.getHeight()/3);
}

private void closeSecondaryStage() {
System.out.println("CLOSING SECONDARY STAGE");
if (secondaryStage != null) {
secondaryStage.close();
secondaryStage = null;
}
}

public static void main(String[] args) {
launch(args);
}
}