FULL PRODUCT VERSION :
1.8.0_141

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows Version 6.1.7601

A DESCRIPTION OF THE PROBLEM :
Selected editable combo-box cell value is altered on table scroll when the row is scroll off-screen if the selected value is not the first element in the combo-box list.


Suspect this bug has existed for some time.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
To reproduce:
- find a cell where a value other that first value in the combo-box list is present (i.e. the second or third value in the list)
- click on a combo-box cell twice to get the combobox component to show (but do not click a third time to open the combo-box popup.
- move the mouse cursor away from the combo-box, and scroll the table with the mouse wheel so that the selected record is off screen
- scroll back up and the value has changed to the first element in the combo-box list.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Expect the property value not to change.
ACTUAL -
TableCell#updateItem() is erroneously invoked with the new value.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package com.blah;

import java.util.Random;
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.scene.Scene;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.ComboBoxTableCell;
import javafx.scene.control.cell.TextFieldTableCell;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;

public class TableWithComboBoxExample extends Application {

    @Override
    public void start(Stage primaryStage) {
        TableView<Contact> contactTable = new TableView<>();
        contactTable.setEditable(true);

        TableColumn<Contact, String> nameCol = new TableColumn<>("Name");
        nameCol.setCellValueFactory(cellData -> cellData.getValue().nameProperty());
        nameCol.setCellFactory(TextFieldTableCell.forTableColumn());
        contactTable.getColumns().add(nameCol);

        String[] strings = {"Friends", "Family", "Work Contacts"};

        TableColumn<Contact, String> categoryCol = new TableColumn<>("Category");
        categoryCol.setCellValueFactory(cellData -> cellData.getValue().categoryProperty());
        categoryCol.setCellFactory(ComboBoxTableCell.forTableColumn(strings));
        contactTable.getColumns().add(categoryCol);

        contactTable.getItems().addAll(
                new Contact("Bill Gates", "Work Contacts"),
                new Contact("Barack Obama", "Friends"),
                new Contact("Tim Cook", "Work Contacts")
        );

        Random random = new Random();
        for (int i = 0; i < 500; i++) {
            contactTable.getItems().add(new Contact(Integer.toString(i), strings[random.nextInt(strings.length)]));
        }

        Scene scene = new Scene(new BorderPane(contactTable), 600, 600);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static class Contact {

        private final StringProperty name = new SimpleStringProperty();
        private final StringProperty category = new SimpleStringProperty();

        public Contact(String name, String category) {
            setName(name);
            setCategory(category);
        }

        public final StringProperty nameProperty() {
            return this.name;
        }

        public final String getName() {
            return this.nameProperty().get();
        }

        public final void setName(final String name) {
            this.nameProperty().set(name);
        }

        public final StringProperty categoryProperty() {
            return this.category;
        }

        public final String getCategory() {
            return this.categoryProperty().get();
        }

        public final void setCategory(final String category) {
            this.categoryProperty().set(category);
        }
    }

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