Adding three (or more) TreeItems at a time, to a TreeView that is not part of the scene graph, causes an infinite TreeCell leak, and eventually an OOM.

To reproduce the problem, follow the steps described in the sample below:
1. select TreeItem1 (without selection the problem doesn't occur - fortunately)
2. remove the TreeView
3. add three TreeItems at a time

Fortunately, this problem is no longer reproducible on Java8, but it is reproducible on the latest Java7 update.


import javafx.application.Application;

import javafx.event.ActionEvent;
import javafx.event.EventHandler;

import javafx.geometry.Insets;

import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.layout.Priority;
import javafx.scene.layout.VBox;

import javafx.stage.Stage;


public class TreeCellLeakTest extends Application {

    private VBox vBox;
    private TreeView<String> treeView;
    private int itemCount = 1;


    public TreeCellLeakTest() {
    }


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

    @Override
    public void start(Stage stage) {
        Label instructionLabel = new Label("Select TreeItem1, click the first button, then the last one, to see the problem.");

        treeView = new TreeView<String>();
        TreeItem<String> rootItem = new TreeItem<String>("Root TreeItem");
        rootItem.setExpanded(true);
        treeView.setRoot(rootItem);
        addTreeItem();

        Button btn1 = new Button("Remove the TreeView from its parent");
        btn1.setOnAction(new EventHandler<ActionEvent>() {

                public void handle(ActionEvent arg0) {
                    vBox.getChildren().remove(treeView);
                }
            });


        Button btn2 = new Button("Bring the TreeView back");
        btn2.setOnAction(new EventHandler<ActionEvent>() {

                public void handle(ActionEvent arg0) {
                    vBox.getChildren().add(1, treeView);
                }
            });


        Button btn3 = new Button("Add Three TreeItems at a time");
        btn3.setOnAction(new EventHandler<ActionEvent>() {

                public void handle(ActionEvent arg0) {
                    addTreeItem();
                    addTreeItem();
                    addTreeItem();
                }
            });

        vBox = new VBox();
        vBox.setSpacing(20);
        vBox.setPadding(new Insets(50));
        vBox.getChildren().addAll(instructionLabel, treeView, btn1, btn2, btn3);
        VBox.setVgrow(treeView, Priority.ALWAYS);

        Scene scene = new Scene(vBox);
        stage.setScene(scene);
        stage.setTitle("TreeCell Leak Test");
        stage.show();
    }

    private void addTreeItem() {
        treeView.getRoot().getChildren().add(new TreeItem<String>("TreeItem " + itemCount));
        itemCount++;
    }

}