Accessing the contend of the Dragboard data during a drag and drop operation (setOnDragEntered, setOnDragOver) does not work as expected.


EXAMPLE (taken from HelloDragAndDrop.java example):

target.setOnDragEntered(new EventHandler <DragEvent>() {
            public void handle(DragEvent event) {

                if (event.getGestureSource() != target && event.getDragboard().hasString()) {
                

                    System.out.println(event.getDragboard().getString().toString()); //##############This will throw an NullPointer Exception.
               
                    target.setFill(Color.GREEN);
                }
                
                event.consume();
            }
        });




        target.setOnDragOver(new EventHandler <DragEvent>() {
            public void handle(DragEvent event) {

                if (event.getGestureSource() != target && event.getDragboard().hasString()) {
                
                 System.out.println(event.getDragboard().getString().toString()); //##############This will throw an NullPointer Exception.

                    event.acceptTransferModes(TransferMode.COPY_OR_MOVE);
                }
                
                event.consume();
            }
        });




If the code is run on Windows, the error does not occur.