Why do I get Memory Leaks in case 1, but not in case 2?

Question

I recently investigated into memory leaks, since we got some when a Window is opened/closed several times.
I discovered the following behavior with ListView:
If I make several instances of a Window, which contains a ListView which uses a fix list as items, there are leaks. (Case 1)
If I make several instances of the ListView directly there are no leaks. (Case 2).
For me both cases seems equal, there's just another wrapper (the window) around the ListView in case 1.
Can someone explain what's going on?
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.ListView;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class TestApp3 extends Application {
    public static void main(String[] args) throws Exception {
        launch(args);
    ObservableList<String> items = FXCollections.observableArrayList("Item1", "Item2");
    public void start(final Stage stage) throws Exception {
        VBox root = new VBox();
        for (int i = 0; i < 100; i++) {
            SubStage subStage = new SubStage(); // Case 1
            subStage.show();
            subStage.hide();
//            ListView<String> listView = new ListView<String>(); // Case 2
//            listView.setItems(items);
        System.gc();
        System.out.println((Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) / 1024 + " KB");
        Scene scene = new Scene(root);
        stage.setScene(scene);
        stage.show();
    private class SubStage extends Stage {
        public SubStage() {
            ListView<String> listView = new ListView<String>();
            listView.setItems(items);
            Scene scene = new Scene(listView);
            setScene(scene);
}EDIT: If I use a TableView in the Substage, there are NO leaks. So is this an issue of the ListView?
Edited by: csh on 10.09.2012 07:40

Answer 1

There is file activity if Open Config Data.vi is being called.  The error is just due to not being able to find the configuration/.ini file.  Root cause could be a few things: the INI file was deleted/not moved/invalid path/whatever.  And the "create file if necessary" input to your use of Open Config Data.vi must be set to False for whatever reason.
Side note:
There were a couple changes to the Config VI's between v6 and v7.
If you were relying on using the default FALSE in Close Config Data.vi in LV6.1, you have to change your code.
From LV7 Upgrade Notes:
<snip>
• The configuration file path input of the Open Config Data VI is a required input. You must specify the configuration file path even if you open a reference to a configuration data object.
• The default of the write configuration file? input of the Close Config Data VI is TRUE. In LabVIEW 6.1 and earlier, the default is FALSE.
<snip>
=====================================================
Fading out. " ... J. Arthur Rank on gong."
Attachments:
OpenConfigData_v7Help.jpg ‏19 KB