如何在java中将JFXProgressBar与我的链接绑定

我试图让java程序从我的服务器下载一个应用程序，通过以下代码获得下载链接：

private void downloadFile(String link) throws Exception {

URL url = new URL(link);

URLConnection conn = url.openConnection();

InputStream is = conn.getInputStream();

int max = conn.getContentLength();

pane.setText(pane.getText()+"\n"+"Downloding files...\nUpdate Size : "+(max/1000000)+" Mb");

BufferedOutputStream fOut = new BufferedOutputStream(new FileOutputStream(new 
   File("update.zip")));
byte[] buffer = new byte[32 * 1024];

int bytesRead = 0;

int in = 0;

while ((bytesRead = is.read(buffer)) != -1) {

    in += bytesRead;

    fOut.write(buffer, 0, bytesRead);
}
fOut.flush();

fOut.close();

is.close();

pane.setText(pane.getText()+"\nDownload Completed Successfully!");

它工作得很好。。。我确实搜索过如何将我的进度条绑定到这个下载链接，但我想不出来。。。。非常感谢您的帮助。

创建一个任务，并以该任务的方法执行下载：

您甚至可以在任务更改时监视其消息：

downloader.messageProperty().addListener(
    (o, oldMessage, newMessage) -> pane.appendText("\n" + newMessage));

如果下载失败，您可能想让用户知道。可以使用任务的属性执行此操作：

downloader.setOnFailed(e -> {
    Exception exception = downloader.getException();

    StringWriter stackTrace = new StringWriter();
    exception.printStackTrace(new PrintWriter(stackTrace));

    TextArea stackTraceField = new TextArea(stackTrace.toString());
    stackTraceField.setEditable(false);

    Alert alert = new Alert(Alert.AlertType.ERROR);
    alert.initOwner(pane.getScene().getWindow());
    alert.setTitle("Download Failure");
    alert.setHeaderText("Download Failed");
    alert.setContextText(
        "Failed to download " + link + ":\n\n" + exception);
    alert.getDialogPane().setExpandableContent(stackTraceField);
    alert.show();
});

任务实现Runnable，因此您可以通过将其传递给任何标准多线程类来启动它：

new Thread(downloader, "Downloading " + link).start();

或：

或：

谢谢你，伙计

downloader.setOnFailed(e -> {
    Exception exception = downloader.getException();

    StringWriter stackTrace = new StringWriter();
    exception.printStackTrace(new PrintWriter(stackTrace));

    TextArea stackTraceField = new TextArea(stackTrace.toString());
    stackTraceField.setEditable(false);

    Alert alert = new Alert(Alert.AlertType.ERROR);
    alert.initOwner(pane.getScene().getWindow());
    alert.setTitle("Download Failure");
    alert.setHeaderText("Download Failed");
    alert.setContextText(
        "Failed to download " + link + ":\n\n" + exception);
    alert.getDialogPane().setExpandableContent(stackTraceField);
    alert.show();
});

new Thread(downloader, "Downloading " + link).start();

CompletableFuture.runAsync(downloader);

ExecutorService executor = Executors.newCachedThreadPool();
executor.submit(downloader);