Javafx webhistory entries insert duplicate browsing histories when I use the textfield assigned for addressbar

Question

Hi I am working on my web browser javafx project where I am storing my browsing history into mysql. There is a bug where everytime I use the addressbar to browse new websites, the history entries insert duplicates.

This is the code that collects and sends data to MySQL.

private void collectData() {
    WebHistory history = web.getEngine().getHistory();
    ObservableList<WebHistory.Entry> entries = history.getEntries();
    DatabaseConnection connectNow=new DatabaseConnection(); 
    
    try {
        connectDB = connectNow.getConnection();
    } catch (SQLException e1) {
        e1.printStackTrace();
    }
    
    String insertTrackData="INSERT INTO `trackdata` (username, sitename, date) VALUES ('"+Session.getSessionUser()+"','"+entries.get(history.getCurrentIndex()).getUrl()+"','"+entries.get(history.getCurrentIndex()).getLastVisitedDate()+"');";
    System.out.println(insertTrackData);
        
    try {
        Statement statement = connectDB.createStatement();
        statement.executeUpdate(insertTrackData);
        
    } catch (Exception e) {
        e.printStackTrace();
        e.getCause();
    }
}

I am wondering if this code is the culprit below

@FXML
private void load(ActionEvent event) {
    web.prefHeightProperty().bind(mainWindow.heightProperty());
    web.prefWidthProperty().bind(mainWindow.widthProperty());
    
    if(!addressBar.getText().contains("https://")) {
        web.getEngine().load("https://" + addressBar.getText());
    } else if(addressBar.getText().contains("https://")) {
        web.getEngine().load(addressBar.getText());
    }
    WebEngine webEngine = web.getEngine();
    
    webEngine.getLoadWorker().stateProperty().addListener((obs, oldValue, newValue) -> {
        if (newValue == Worker.State.SUCCEEDED) {
            WebHistory history = web.getEngine().getHistory();
            ObservableList<WebHistory.Entry> entries = history.getEntries();
            addressBar.setText(entries.get(history.getCurrentIndex()).getUrl());
            
            Stage stage = (Stage) addressBar.getScene().getWindow();
            stage.setTitle(entries.get(history.getCurrentIndex()).getTitle());
            collectData();
        } else if (newValue == Worker.State.FAILED) {
            System.out.println("Loading failed");
        }
     });
}

The console shows this:

INSERT INTO trackdata (username, sitename, date) VALUES ('m','https://www.google.com.hk/','Fri Nov 19 10:48:34 CST 2021');

INSERT INTO trackdata (username, sitename, date) VALUES ('m','https://edition.cnn.com/','Fri Nov 19 10:48:55 CST 2021');

INSERT INTO trackdata (username, sitename, date) VALUES ('m','https://www.imdb.com/','Fri Nov 19 10:49:17 CST 2021');

Note that the value only duplicates when I enter a new address in the addressbar.

I believe that the load method creates a new instance of ObservableList entries = history.getEntries(); ? Maybe? — Jinyoung Chang, Nov 19 '21 at 03:09

score 3 · Accepted Answer · answered Nov 19 '21 at 03:27

3

Every time you call method load you add another listener to the same state property of the same WebEngine and each of those listeners executes. That's why your console shows the first URL once, the second URL twice, the third URL three times and so on.

You only need to add the listener once.

answered Nov 19 '21 at 03:27

Abra

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Thank you, instead of calling a method every time I press the load button, I used initialize to call the method once when the program runs – Jinyoung Chang Nov 30 '21 at 01:14

Javafx webhistory entries insert duplicate browsing histories when I use the textfield assigned for addressbar

1 Answers1